Electrochemistry Questions

We provide electrochemistry practice exercises, instructions, and a learning material that allows learners to study outside of the classroom. We focus on electrochemistry skills mastery so, below you will get all questions that are also asking in the competition exam beside that classroom.

List of electrochemistry Questions

Question No Questions Class
1 Find the over voltage if electrolysis of brine solution requires ( 2.19 mathrm{V} ) to produce
( mathrm{H}_{2} ) and ( mathrm{Cl}_{2} . ) (Write your answer upto two
decimal places)
Given: ( boldsymbol{E}_{boldsymbol{H}^{+} / boldsymbol{H}}^{boldsymbol{o}}=mathbf{0} ) and ( boldsymbol{E}_{C l^{-} / C l_{2}}^{o}= )
( -1.36 V )
12
2 When a corroded metal object is rubbed
by a sand paper then:
A. outer metal surface is removed
B. metal becomes thin
c. outer corroded layer will be removed
D. all of the above
12
3 The life span of a Daniel cell may
increased by:
A. large Cu electrode
B. lowering of CuSO ( _{4} ) concentration
C. lowering of ZnSO ( _{4} ) concentration
D. large zinc electrode
12
4 Resistance of a cconductivity cell filled with a solution of an electrolyte of concentration ( 0.1 M ) is ( 100 Omega ). The
conductivity of this solution is ( 1.29 S m^{-1} . ) Resistance of the same cell
when filled with ( 0.02 ~ M ) of the same
solution is ( 520 Omega ). The molar
conductivity of ( 0.02 M ) solution of the electrolyte will be:
A ( cdot 124 times 10^{-4} mathrm{Sm}^{2} mathrm{mol}^{-1} )
В. ( 1240 times 10^{-4} mathrm{Sm}^{2} mathrm{mol}^{-1} )
c. ( 1.24 times 10^{-4} mathrm{Sm}^{2} mathrm{mol}^{-1} )
D. ( 12.4 times 10^{-4} mathrm{Sm}^{2} mathrm{mol}^{-1} )
12
5 The ( mathrm{E}^{o} ) for reduction of ( mathrm{HNO}_{2} ) to ( mathrm{NO} ) is
( 0.99 mathrm{V} ) and ( mathrm{E}^{circ} ) for reduction of ( mathrm{NO}_{3}^{-} ) to
( mathrm{HNO}_{2} ) is ( 0.94 mathrm{V} . ) The equilibrium
constant at ( 25^{circ} mathrm{C} ) for the
disproportionation of 3 mole of aqueous
( mathrm{HNO}_{2} ) to yield ( mathrm{NO} ) and ( mathrm{N} mathrm{O}_{3}^{-} ) ions is:
A. ( K_{c}=344.64 )
В. ( K_{c}=336.97 )
c. ( K_{c}=639.73 )
D. None of these
12
6 When the terminals of a cell of e.m.f. ( 1.5 v )
are connected to an ammeter of
resistance ( 4 Omega, ) the ammeter read 0.30
amp. which of the following statements
is/are correct?
This question has multiple correct options
A. The cell is non-ideal
B. If a ( 4 Omega ) resistor is also connected across terminals of the cell, the ammeter will read 0.50 amp.
c. If a ( 4 Omega ) resistor is also connected across terminals of the cell, one-third of the electrical power generated will dissipate as heat within the cell
D. If a voltmeter of resistance ( 4 Omega ) is used to measure potential difference between terminals of the cell, it will read ( 1.2 mathrm{v} )
12
7 After electrolysis of NaCl solution with
inert electrodes for a certain period of
time, ( 600 mathrm{mL} ) of the solution was left. Which was found to be ( 1 mathrm{N} ) in ( mathrm{NaOH} ) During the same time, 31.75 g ( mathrm{Cu} ) deposited in the copper voltameter in series with the electrolytic cell. Calculate the percentage yield of NaOH obtained.
A. ( n=60 % )
a
B . ( n=50 % )
c. ( n=70 % )
D. None of these
12
8 Observe the given diagram and fill in
the blanks by choosing the correct
option.
( mathbf{A} cdot mathbf{x}-H_{2(g)} ) at 1 atm ( , y-10^{-2} M H^{+}, z^{-} ) Finely divided ( P t )
B . ( x-H_{2(g)} ) at 1 bar, ( y-1.00 M H^{+}, z ) – Finely divided Pt
C. ( x-1.00 M H^{+}, y-H_{2(g)} ) at 1 bar, ( z ) – Finely divided ( N ) i
D. ( x-H_{2}(g) ) at 1 bar, ( y-1.00 M H^{+}, z ) – Pt granules
12
9 State True or False.
The ratio of gases liberated at cathode
and anode during electrolysis of ( mathrm{CH}_{3} ) COONa(aq) is 1: 3
A. True
B. False
12
10 Which of the following complexes has lowest molar conductance?
A. ( operatorname{CoCl}_{3} .3 mathrm{NH}_{3} )
в. ( operatorname{CoCl}_{3} .4 mathrm{NH}_{3} )
c. ( operatorname{CoCl}_{3} .5 mathrm{NH}_{3} )
D. ( operatorname{CoCl}_{3} .6 mathrm{NH}_{3} )
12
11 The specific conductivity of ( N / 10 K C l )
solution at ( 20^{circ} mathrm{C} ) is 0.0212 ohm ( ^{-1} )
( c m^{-1} ) and the resistance of the cell
containing this solution at ( 20^{circ} mathrm{C} ) is 55
ohm. The cell constant is:
A ( cdot 3.324 mathrm{cm}^{-1} )
B. ( 1.166 mathrm{cm}^{-1} )
( mathbf{c} cdot 2.372 mathrm{cm}^{-1} )
D. ( 3.682 mathrm{cm}^{-1} )
12
12 The equivalent conductance of NaCl at concentration ( C ) and at infinite dilution
( operatorname{are} lambda_{C} ) and ( lambda_{infty} ) respectively. The correct
relationship between ( lambda_{C} ) and ( lambda_{infty} ) is
given as: (Where the constant B is positive)
A ( cdot lambda_{C}=lambda_{infty}-(B) sqrt{C} )
в. ( lambda_{C}=lambda_{infty}+(B) sqrt{C} )
c. ( lambda_{C}=lambda_{infty}+(B) C )
D. ( lambda_{C}=lambda_{infty}-(B) C )
12
13 (a) Following reactions occur at cathode during the electrolysis of aqueous sodium chloride solution:
( N a^{+}(a q)+e^{-} longrightarrow N a(s) E^{0}= )
( -2.71 V )
( boldsymbol{H}^{+}(boldsymbol{a} boldsymbol{q})+boldsymbol{e}^{-} longrightarrow frac{mathbf{1}}{mathbf{2}} boldsymbol{H}_{2}(boldsymbol{g}) boldsymbol{E}^{0}= )
( 0.00 V )
On the basis of their standard reduction
electrode potential ( left(boldsymbol{E}^{0}right) ) values
which reaction is feasible at the
cathode and why?
(b) Why does the cell potential of mercury cell remain constant throughout its life?
12
14 A current of 5 amperes is passed
through ( mathrm{AlCl}_{3} ) solution for 15 minutes using Pt electrodes, when 0.504 g of ( A l ) is produced. What is the molar mass of Al?
12
15 Given
( boldsymbol{E}_{boldsymbol{C r}^{3+} / boldsymbol{C r}}^{circ}=-boldsymbol{0 . 7 4} boldsymbol{V} ; boldsymbol{E}_{M n O_{4}^{-} / M n^{2+}}^{circ}= )
( +1.51 V )
( boldsymbol{E}_{C r_{2} O_{7}^{2-} / C r^{3+}}^{circ}=+mathbf{1 . 3 3} boldsymbol{V} ; boldsymbol{E}_{C l / C l^{-}}^{circ}= )
( +1.36 V )
based on the data given above, strongest oxidizing agent will
be
A. ( M n^{2+} )
в. ( M n O_{4}^{-} )
c. ( C l )
D. ( C r^{3} )
12
16 In the hydrogen atom, the energy difference between the states ( n=2 ) and
( n=3 ) is ( mathrm{E} ) eV. The ionisation potential of ( mathrm{H} )
atom is:
A. 3.2
в. 5.6 Е
( c cdot 7.2 E )
D. 13.2 E
12
17 Assertion
We apply paint on iron articles.
Reason
Iron is a metal, metals rust when they
come in contact of direct air so to
prevent rusting.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
18 Assertion
Li electrode always acts as anode in
voltaic cell.
Reason
Li electrode has lowest SRP among all
the electrodes.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct.
12
19 The weight in grams of ( O_{2} ) formed at ( P t )
anode during the electrolysis of aq.
( K_{2} S O_{4} ) solution during the passage of one coulomb of electricity is:
A ( cdot frac{16}{96800} )
в. ( frac{8}{96500} )
c. ( frac{32}{96500} )
D. ( frac{64}{96500} )
12
20 Pure water consists entirely of (ions /
molecules)
12
21 In a galvanic cell, electrons flow through connecting wires from:
A. anode to cathode
B. cathode to anode
c. top to bottom
D. anode
12
22 Which of the following is/are nondisposable batteries? This question has multiple correct options
A. Dry cell
B. Mercury cell
c. Lead acid battery
D. ( N i-C d ) battery
12
23 According to Kohlrausch law, the limiting value of molar conductivity of
an electrolyte ( A_{2} B ) is:
( mathbf{A} cdot Lambda_{A}^{infty}+Lambda_{B}^{infty} )
B ( cdot Lambda_{A}^{infty}-Lambda_{B}^{infty} )
( mathbf{C} cdot Lambda_{A}^{infty}+frac{1}{2} Lambda_{B}^{infty} )
( mathbf{D} cdot 2 Lambda_{A}^{infty}+Lambda_{B}^{infty} )
12
24 Pick out the pair in which the energy change of one is reverse of the energy change in the other :
(1) radio
(2) fluorescent lamp
(3) toaster
(4) photoelectric cell
A . 1 and 2
B. 2 and 3
( c cdot 2 ) and 4
D. 3 and 4
12
25 What is the charge of 96 amu of ( S^{2-} ? )
A ( .2 C )
B . ( 3.2 times 10^{-19} C )
c. ( 9.6 times 10^{-19} C )
D. ( 6 C )
12
26 The equivalent conductance of ( B a^{2+} )
and ( C l^{-} ) are respectively 127 and 76
( operatorname{oh} m^{-1} c m^{2} e q^{-1} ) at infinite dilution.
What will be the equivalent
conductance of ( B a C l_{2} ) at infinite
dilution?
A . 139.5 ohm ( ^{-1} mathrm{cm}^{2} ) eq ( ^{-1} )
B . 203 ohm ( ^{-1} mathrm{cm}^{2} ) eq( ^{-1} )
c. 279 ohm ( ^{-1} mathrm{cm}^{2} ) eq ( ^{-1} )
D. 101.5 ohm ( ^{-1} mathrm{cm}^{2} ) eq ( ^{-1} )
12
27 If Molar conductivity of ( C a^{2+}=119 & )
Molar conductivity of ( C l^{=} 71 ) then find
the molar conductivity of ( C a C l_{2} )
A .341
в. 261
( c cdot 126 )
D. 431
12
28 Match List I with List II. 12
29 Assertion: The more negative the standard reduction potential, the more is its ability to displace hydrogen from acids.

Reason: Ability to displace hydrogen from acids translates to the strength of the reductant.
A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c. Assertion is true but Reason is false
D. Assertion is false but Reason is true
E. Both Assertion and Reason are false

12
30 The specific conductivity of ( N / 10 K C l )
solution at ( 20^{circ} mathrm{C} ) is 0.0212 oh ( m^{-1} mathrm{cm}^{-1} )
and the resistance of the cell containing
this solution at ( 20^{circ} C ) is 55 ohm. The
cell constant is:
A ( cdot 4616 mathrm{cm}^{-1} )
B. ( 1.166 mathrm{cm}^{-1} )
c. ( 2.173 mathrm{cm}^{-1} )
D. ( 3.324 mathrm{cm}^{-1} )
12
31 Calculate ( Delta G ) for the following cell
reaction.
( boldsymbol{Z} boldsymbol{n}_{(s)}+boldsymbol{A} boldsymbol{g}_{2} boldsymbol{O}_{(s)}+boldsymbol{H}_{2} boldsymbol{O}_{(l)} rightarrow boldsymbol{Z} boldsymbol{n}_{(a q)}^{2+}+ )
( mathbf{2} boldsymbol{A} boldsymbol{g}_{(s)}+mathbf{2} boldsymbol{O} boldsymbol{H}^{-}(boldsymbol{a} boldsymbol{q}) )
( boldsymbol{E}_{A boldsymbol{g}^{+} / boldsymbol{A} boldsymbol{g}}^{0}=+mathbf{0 . 8 0} boldsymbol{V} ) and ( boldsymbol{E}_{boldsymbol{Z n}^{+2} / Z boldsymbol{n}}^{0}= )
( -0.76 V )
A . -305 k ( J / operatorname{mol} )
в. ( -301 k J / ) mol
c. ( 305 k J / ) mol
D. 301 kJ/mol
12
32 Characteristics & Relation 12
33 faraday ( = )
A ( .10000 C )
B. ( 95000 C )
c. ( 96.5 C )
D. 96500 ( C )
12
34 An electrochemical cell stops working
after some time because:
A. electrode potential of both the electrodes becomes zero
B. electrode potential of both the electrodes become equal
C . one of the electrode is eaten away.
D. the reaction starts proceeding in opposite direction
12
35 Why zinc metal is used for
galvanisation?
A. zinc get corroded easily than iron
B. zinc does not corrode
c. corrosion constant of iron increase
D. All of the above
12
36 Why does the bulb glow, when the electric current passes through it?
A. Due to the lighting effect of electric current
B. Due to the magnetic effect of electric current.
c. Due to the chemical effect of electric current
D. Due to the heating effect of electric current
12
37 The potential of a hydrogen electrode at ( boldsymbol{p} boldsymbol{H}=mathbf{1} ) is
A. 0.059 volt
B. 0 volt
c. -0.059 volt
D. 0.59 volt
12
38 Acetic acid is titrated with ( N a O H )
solution. Which of the following statement is correct for this titration?
A. Conductane increases upto equivalence point, then it it decreases
B. Conductance decreases upto equivalence point, then it increases
c. First conductance increases slowly upto equivalence point and then increases rapidly
D. First conductance increases slowly upto equivalence point and then drops rapidly
12
39 Voltaic cell is same as:
A. galvanic cell
B. electrolytic cell
C. fuel cell
D. lead cell
12
40 ( ln ) a daniel cell, if ( boldsymbol{A}left(boldsymbol{E}^{o}=-mathbf{0 . 7 6} boldsymbol{C}right) ) and
( Bleft(E^{o}=-2.36 Vright) ) half cells are taken
then:
( A cdot B ) acts as anode
B. ( A ) acts as anode
c. ( B ) acts as cathode
D. cannot be predicted
12
41 0.68 What is the relationship between Gibbs free energy of the cell reaction
in a galvanic cell and the emf of the cell? When will the maximum work
be obtained from a galvanic cell?
12
42 Q2. What is standard hydrogen electrode? For what purpose it is used? What are signs of oxidation
potential and reduction potential decided by using SHE (Standard hydrogen electrode)?
12
43 Which of the following is one of the most common application of chemical effects of electric current?
A. Electrophoresis
B. Electroplating
c. Galvanization
D. Mineralization
12
44 the blanks by choosing an appropriate
option.

In the given cell, hydrogen and oxygen
are bubbled through porous ( (i) ) electrodes into concentrated aqueous
( (i i) ) solution. Catalysts like finely
divided ( (i i i) ) or ( (i v) ) metal are
incorporated into the electrodes for increasing the rate of electrode
reactions.
A. (i)- Hydrogen, (ii)-Potassium hydroxide, (iii)palladium, (iv)-platinum
B. (i)- Oxygen
(ii)- Hydrogen chloride
(iii)- Manganese, (iv)- Iron
c. (i)- Carbon
(ii)- sodium hydroxide
(iii)- Platinum, (iv) palladium
D. (i)- Graphite,
(ii)- Sodium Chloride
(iii)- Nickel, (iv)Platinum

12
45 Number of Faradays (F) required to reduce 3 mol of ( M n O_{4}^{ominus} ) to ( M n^{2+} ) is: 12
46 ( lambda^{infty} ) of ( N H_{4} O H ) at infinite dilution is
( boldsymbol{S} boldsymbol{c m}^{2} boldsymbol{m o l}^{-1} operatorname{given} boldsymbol{lambda}^{infty} boldsymbol{o f} )
( O H^{-}=174, lambda^{infty} ) if ( C l^{-}=66 ) and ( lambda^{infty} ) of
( N H_{4} C l=130 S c m^{2} m o l^{-1} )
A . 140
в. 218
c. 238
D. 198
12
47 What is the potential of a half cell consisting of zinc electrode in ( 0.01 mathrm{M} )
( Z n S O_{4} ) solution of
( mathbf{2 5}^{circ} boldsymbol{C} ?left[boldsymbol{E}^{boldsymbol{o}}=mathbf{0 . 7 6 3} boldsymbol{V}right] )
12
48 What are fuel cells? How are they
different from Galvanic cells? Give the
construction of hydrogen-oxygen fuel cells.
12
49 The resistance of solution decreases
with increase in temperature.
A. True
B. False
12
50 ( C H_{3} C O O H ) is titrated with ( N a O H )
solution. Which of the following
statement is true?
A. Conductance decreases upto equivalence point, after which it increases.
B. conductance increases upto equivalence point, after which it decreases.
c. conductance first increases (but not rapidly) upto equivalence point and then increases rapidly after equivalence point.
D. None of the above
12
51 How many coulombs of electricity are required for the oxidation of one mole of
water to dioxygen?
A ( .9 .65 times 10^{4} C )
в. ( 1.93 times 10^{4} C )
c. ( 1.93 times 10^{5} mathrm{C} )
D. ( 19.3 times 10^{5} C )
12
52 Answer the following, in short, using a
maximum 30 words.
Explain Faraday’s first law of electrolysis
12
53 In electrochemical corrosion. the metal
undergoing corrosion:
A. acts as anode
B. acts as cathode
c. undergoes reduction
D. liquifies
12
54 The resistance of ( 0.5 mathrm{M} ) solution of an
electrolyte in a cell was found to be 50
Omega. If the electrodes in the cell are ( 2.2 mathrm{cm} )
a part and have an area of ( 4.4 mathrm{cm}^{2} ) than
the molar conductivity ( left(operatorname{in} S m^{2} m o l^{-1}right) )
of the solution is:
A . 0.2
B. 0.02
c. 0.002
D. None of these
12
55 When lead storage battery is charged:
A. lead dioxide dissolves
B. sulphuric acid is regenerated
C. the lead electrode becomes coated with lead sulphate
D. the amount of sulphuric acid decreases
12
56 Q1. Define electrochemical cell. 12
57 Which one is not correct for e.m.f. of a
galvanic cell?
This question has multiple correct options
( mathbf{A} cdot E_{c e l l}=E_{O P_{a n o d e}}+E_{R P_{c a t h a d e}} )
B. ( E_{text {cell}}=E_{O P_{L H S}}+E_{R P_{text {RHS}}} )
C ( . E_{text {cell}}= ) higher oxidation potential – lower oxidation potential
D. ( E_{text {cell}}= ) lower oxidation potential – higher oxidation potential
12
58 Calculate the molarity of a solution
containing ( 5 g ) of NaOH dissolved in the
product of a ( boldsymbol{H}_{2}-boldsymbol{O}_{2} ) fuel cell operated
at ( 1 A ) current for 595.1 hours.
(Assume ( 1 F=96500 mathrm{C} / mathrm{mol} ) of
electrons and molecular weight of NaOH as ( 40 mathrm{g} ) mol ( ^{-1} ) )
A . 0.05 M
B. 0.025 м
( c .0 .1 mathrm{m} )
D. 0.075 м
E. 1 M
12
59 Which of the following reaction occurs at
the cathode during the charging of lead
storage battery?
( mathbf{A} cdot P b rightarrow P b^{2+}+2 e^{-} )
B ( cdot P b^{2+}+2 e^{-} rightarrow P b )
( mathbf{c} cdot P b O_{2}+S O_{4}^{2-} rightarrow P b S O_{4} )
D ( cdot P b S O_{4}(s)+2 H_{2} O rightarrow P b O_{2}(s)+4 H^{+}+S O_{4}^{2-}+2 e^{-} )
12
60 The potential of a hydrogen electrode in
a solution with ( mathrm{pH}=5 ) at ( 25^{circ} mathrm{C} ) is:
A ( .+0.059 )
B. 0.59
c. -0.295
D. 0.295
12
61 Assertion
Standard hydrogen electrode is a half cell having ( 1 M H^{+} ) concentration
bubbled with hydrogen at any pressure
Reason

A hydrogen electrode will always show ( boldsymbol{E}_{c e l l}=mathbf{0 . 0 0} boldsymbol{V} )
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect

12
62 Consider the cell:
( boldsymbol{Z} boldsymbol{n} mid boldsymbol{Z} boldsymbol{n}^{2+}(boldsymbol{a q})(boldsymbol{1} . boldsymbol{0} boldsymbol{M}) | boldsymbol{C u}^{2+}(boldsymbol{a q}) )
The standard reduction potential are ( 0.350 mathrm{V} ) for ( boldsymbol{C u}^{2+}(boldsymbol{a q})+boldsymbol{2} boldsymbol{e}^{-} rightarrow boldsymbol{C u} )
and ( -0.763 mathrm{V} ) for ( mathrm{Zn}^{2+}(a q)+2 e^{-} rightarrow )
( Z n )
The EMF (in V) of the cell is (write your answer as nearest integer):
12
63 Question 16. Three electrolytic cells A, B, C containing solutions of
ZnSO4, AgNO3 and CuSO4 respectively are connected in series. A steady
current of 1.5 amperes was passed through them until 1.45 g of silver
deposited at the cathode of cell B. How long did the current flow? What
mass of copper and zinc were deposited? [Atomic masses;
Cu=63.5, Zn= 65.3 ; Ag = 108]
12
64 At ( 298 mathrm{K} ) temperature, ( A ) hydrogen gas electrode is made by dipping platinum wire in a solution of HCl of ( mathrm{pH}=10 ) and
by passing hydrogen gas around the platinum were at one atm pressure. The potential of electrode would be?
( mathbf{A} cdot 0.59 mathrm{V} )
B. ( 0.118 v )
c. ( 1.18 v )
D. ( 0.059 mathrm{V} )
12
65 The products formed when an aqueous solution of ( N a B r ) is electrolysed in a
cell having inert electrodes are :
A. ( N a ) and ( B r_{2} )
B. ( N a ) and ( O_{2} )
( mathrm{c} cdot mathrm{H}_{2}, mathrm{Br}_{2} ) and ( mathrm{NaOH} )
D. ( H_{2} ) and ( O_{2} )
12
66 The amount of ( N a ) produced by the passage of 2 moles of electrons through the fused ( N a C l ) is ( _{-}—–8 )
A . 23
B. 46
c. 11.5
D. 34.5
12
67 Amount of ( C u ) deposited from
( boldsymbol{C u} boldsymbol{S O}_{4}(boldsymbol{a q}) ) when 5 amp current is
passed for 965 seconds through it, is ( boldsymbol{C u}=mathbf{6 3 . 5 g m o l}^{-1} mathbf{)} )
A . ( 1.6 g )
B. ( 3.2 g )
c. ( 1.45 g )
D. ( 2.9 g )
12
68 Question 5. Aqueous copper sulphate solution and aqueous silver
nitrate solution are electrolysed by 1 ampere current for 10 min in
separate electrolytic cell. Will the mass of copper and silver deposited on
the cathode be same or different? Explain your answer.
12
69 0.5 Which of the following statement is not correct about an inert electrode
in a cell?
(a) It does not participate in the cell reaction
(b) It provides surface either for oxidation or for reduction reaction
(c) It provides surface for conduction of electrons
(d) It provides surface for redox reaction
12
70 Which of the following reactions occurs
at cathode during charging of storage
battery?
( mathbf{A} cdot P b^{2+}+2 e^{-} rightarrow P b )
B ( cdot P b rightarrow P b^{2+}+2 e^{-} )
( mathbf{c} cdot P b^{2+}+S O_{4}^{2-} rightarrow P b S O_{4} )
D ( cdot P b S O_{4}+2 H_{2} O rightarrow P b O_{2}+4 H^{+}+S O_{2}^{2-}+2 e^{-} )
12
71 State Faraday’s first law of electrolysis. Write any ‘two’ uses of each of the following
(a) ( boldsymbol{H}_{2} boldsymbol{S} boldsymbol{O}_{4} )
(b) Chlorine
Distinguish between crystalline solids and amorphous solids. A solution of a substance having mass ( 1.8 times 10^{-3} k g ) has the osmotic pressure
of 0.52 atm at ( 280 mathrm{K} ). Calculate the
molar mass of the substance used.
[Volume ( =1 d m^{3}, R= )
( left.8.314 J K^{-1} m o l^{-1}right] )
12
72 Calculate ( boldsymbol{E}^{circ} ) of the following half-cell
reaction at ( 298 K )
( boldsymbol{A} boldsymbol{g}left(boldsymbol{N} boldsymbol{H}_{3}right)_{2}^{+}+boldsymbol{e}^{-} rightarrow boldsymbol{A} boldsymbol{g}+boldsymbol{2} boldsymbol{N} boldsymbol{H}_{3} )
( boldsymbol{A} boldsymbol{g}^{+}+boldsymbol{e}^{-} rightarrow boldsymbol{A} boldsymbol{g} ; boldsymbol{E}_{A boldsymbol{g}^{+} / A boldsymbol{g}}^{circ}=mathbf{0 . 8 0} boldsymbol{V} )
( boldsymbol{A} boldsymbol{g}left(boldsymbol{N} boldsymbol{H}_{3}right)_{2}^{+} rightleftharpoons boldsymbol{A} boldsymbol{g}^{+}+boldsymbol{2} boldsymbol{N} boldsymbol{H}_{3} ; boldsymbol{K}=boldsymbol{6} times )
( 10^{-8} )
12
73 Define molar conductivity. How it is
related with conductivity.
12
74 . 21 Conductivity of an electrolytic solution depends on
(a) nature of electrolyte
(b) concentration of electrolyte
(c) power of AC source
(d) distance between the electrodes
12
75 What is the voltage of the voltaic cell ( Z nleft|Z n^{2+}right|left|C u^{2+}right| C u ) at ( 298 K ) if
( left[Z n^{2+}right]=0.2 M ) and ( left[C u^{2+}right]=4.0 M ? )
( boldsymbol{C u}^{2+}+boldsymbol{2} boldsymbol{e}^{-} rightarrow boldsymbol{C u} boldsymbol{E}^{circ}=+mathbf{0 . 3 4} boldsymbol{V} )
( Z n^{2+}+2 e^{-} rightarrow Z n E^{circ}=-0.76 V )
( left[text { Note }: boldsymbol{E}=boldsymbol{E}^{circ}-(mathbf{0 . 0 5 9 1} / boldsymbol{n})(log boldsymbol{Q})right. )
A. ( +1.10 V )
в. ( -1.10 mathrm{V} )
c. ( +1.07 V )
D. ( +1.14 V )
E . ( -1.07 mathrm{V} )
12
76 What current strength in amperes will be required to liberate 10 gm of iodine from potassium iodide solution in one hour? (Equivalent mass of lodine is 127 ). 12
77 The solution of a salt of a metal of
atomic mass 112 was electrolysed for 15 minutes with a current of
1.5 ampere. The mass of the metal
deposited was ( 0.788 g ). Find the valency of the metal.
( A cdot 1 )
B. 2
( c cdot 3 )
( D )
12
78 Question 1. Can absolute electrode potential of an electrode be
measured?
Colin N
anl+he diff
12
79 The ( E_{text {cell}} ) for a given cell is 1.2346 and
( 1.2340 V ) at ( 300 mathrm{K} ) and ( 310 mathrm{K} )
respectively. Calculate the change in
entropy during the cell reaction if the redox change involves three electrons.
A. ( -17.37 mathrm{JK}^{-1} )
B. ( +17.37 J K^{-1} )
c. ( 173.7 J K^{-1} )
D. ( 5.79 J K^{-1} )
12
80 A voltaic cell is represented as
( boldsymbol{A}_{(s)}left|boldsymbol{A}_{(a q)}^{+2}right|left|boldsymbol{B}_{(a q)}^{+2}right| boldsymbol{B}_{(s)} . ) Which of the
following statements of false regarding
the above cell?
A. The double vertical line indicates salt bridge
B. ( A ) is called the anode and ( B ) is called the cathode
C. The cell reactions are represented as ( A^{2+}+2 e^{-} rightarrow A ) and ( B rightarrow B^{2+}+2 e^{-} )
D. None of the above
12
81 A tester is used to check the conduction
of electricity through two liquids, labelled ( A ) and ( B ). It is found that the
bulb of the tester glows brightly for liquid A while it glows very dim for liquid B. You would conclude that:
A. liquid ( A ) is a better conductor than liquid ( B )
B. liquid ( B ) is a better conductor than liquid ( A )
c. both liquids are equally conducting
D. conducting properties of liquid cannot be compared in this manner.
12
82 If the ( H^{+} ) concentration decreased from
( 1 mathrm{M} ) to ( 10^{-4} mathrm{M} ) at ( 25^{circ} mathrm{C} ) for the couple
( M n O_{4}^{-} / M n^{2+}, ) then the oxidising
power of the ( M n O_{4}^{-} / M n^{2+} ) couple decreases by
A . -0.18v
B. 0.18V
c. ( 0.38 v )
D. -0.38V
12
83 The electrolysis of aqueous solution of
( boldsymbol{C u B r _ { 2 }} ) using platinum electrode would
leads to:
This question has multiple correct options
A. ( B r_{2} ) gas at anode
B. ( B r_{2} ) gas at anode and ( O_{2} ) gas at cathode
c. copper(s) at cathode
D. ( H_{2} ) gas at cathode
12
84 If the lead-acid battery is discharged too far or left in a discharged condition, it cannot be recharged any more because:
A. terminal voltage becomes too low
B. hard lead sulphate forms on its electrodes
c. internal resistance of the cell becomes very high
D. internal resistance of the cell becomes too low
12
85 The conductivity of ( 0.20 mathrm{M} ) solution of
( K C l ) at ( 298 mathrm{K} ) is ( 0.0248 S c m^{-1} )
Calculate its molar conductivity.
A ( cdot 112 operatorname{Scm}^{2} m o l^{-1} )
B. ( 124 S c m^{2} m o l^{-1} )
( mathbf{c} cdot 136 S c m^{2} m o l^{-1} )
D. 148 Scm ( ^{2} ) mol ( ^{-1} )
12
86 Assertion
Anode is the electrode at which
oxidation occurs and cathode is the
electrode at which reduction occurs.
Reason

Anode and cathode in electrochemical
cells and electrolytic cells have opposite
polarity.
A. Both assertion and reason are correct and reason is the correct explanation for assertion
B. Both assertion and reason are correct but reason is not the correct explanation for assertion
C. Assertion is correct but reason is incorrect
D. Assertion is incorrect but reason is correct

12
87 Which of the following condition is correct for operation of electrolytic cell?
A. ( triangle G=0, E=0 )
в. ( triangle G0 )
c. ( triangle G>0, E0, E>0 )
12
88 When a steady current of ( 2 A ) was
passed through two electrolytic cells ( boldsymbol{A} )
and ( B ) containing electrolytes ( Z n S O_{4} )
and ( C u S O_{4} ) connected in series, ( 2 g ) of
( C u ) were deposited at the cathode of
cell ( B )
How long did the current flow?
What mass of ( Z n ) was deposited at
cathode of cell ( boldsymbol{A} ) ?
[Atomic mass: ( C u= )
( mathbf{6 3 . 5 g} mathbf{m o l}^{-mathbf{1}}, mathbf{Z n}=mathbf{6 5 g} mathbf{m o l}^{-mathbf{1}} ; mathbf{1} mathbf{F}= )
( left.96500 C m o l^{-1}right] )
12
89 Why is anode in galvanic cell considered to be -ve and cathode to be
+ve electrode?
12
90 If four moles of electrons are transferred
from anode to cathode in a experiment
on electrolysis of water, then total volume of the two gases produced at
STP will be:
( mathbf{A} cdot 224 L )
B. ( 72.6 L )
c. ( 67.2 L )
D. ( 89.4 L )
12
91 The correct order of equivalent
conductance at infinite dilution of
( L i C l, N a C l ) and ( K C l ) is :
A. ( L i C l>N a C l>K C l )
в. ( K C l>N a C l>L i C l )
c. ( N a C l>K C l>L i C l )
D. ( L i C l>K C l>N a C l )
12
92 An element ( A ) combines with oxygen to
form an oxide ( A O . ) This oxide is
electrically conducting. Find
(A) the number of valence electrons in ( A )
(B) the group to which the element ( boldsymbol{A} )
belongs
(C) the formula of the compound when
( A ) reacts with chlorine
12
93 For a reaction, ( boldsymbol{A}(s)+mathbf{2} boldsymbol{B}^{+} leftrightharpoons boldsymbol{A}^{2+}+ )
( 2 B, K_{c} ) has been found to be ( 10^{12} ). The
( boldsymbol{E}_{c e l l}^{o} ) is:
A . ( 0.354 V )
в. ( 0.708 V )
c. ( 0.0098 V )
D. ( 1.36 V )
12
94 The resistance of a conductivity cell
containing ( 0.001 M K C l ) solution at
( 298 K ) is ( 1500 Omega . ) What is the cell
constant (in ( mathrm{mm}^{-1} ) ) if the conductivity
of ( 0.001 M K C l ) solution is ( 2 times 10^{-3} mathrm{s} )
( mathrm{mm}^{-1} ? )
12
95 Assertion: Input of energy is required by electrolytic cells. Reason: Electrolytic cells have just one container, while voltaic cells have two
A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c. Assertion is true but Reason is false
D. Assertion is false but Reason is true
E. Both Assertion and Reason are false
12
96 Which one is/ are correct among the
following?

Given, the half cell emf’s ( E_{C u^{+2} / C u}^{0}= )
( mathbf{0 . 3 3 7}, boldsymbol{E}_{boldsymbol{C u}^{+1} / boldsymbol{C u}}^{mathbf{0}}=mathbf{0 . 5 2 1} )
A . ( C u^{+1} ) disproporationates
B. ( C u ) and ( C u^{2+} ) comproportionates (reverse of disproportionation into ( C u^{+} ) )
C. ( E_{C u / C u^{+2}}^{0}+E_{C u^{2} / C u}^{0} ) is positive
D. All of these

12
97 Nickel and cadmium are used in
combination.
A. As a catalyst
B. In alloys that can resisthigh pressure
c. In electric batteries having a very long life
D. In cooking utensils
12
98 The EMF (in Volts) for the following electrodes are
( boldsymbol{P t}, boldsymbol{H}_{2} mid boldsymbol{H}_{2} boldsymbol{S} boldsymbol{O}_{4}(boldsymbol{p} boldsymbol{H}=mathbf{2 . 0}) )
12
99 State Kohlrausch Law, and write
mathematical expression of molar conductivity of the given solution at infinite dilution.
12
100 A device that converts energy of
combustion of fuels like hydrogen and methane, directly into electrical energy
is known as:
A. dynamo
B. Ni-Cd cell
c. fuel cell
D. electrolytic cell
12
101 Normal calomel electrode has e.m.f. of
( 0.67 mathrm{V} ) at ( 25^{circ} mathrm{C} ). Calculate pH of solution.
The oxidation potential of calomel electrode on ( H ) scale is ( 0.28 V ) (nearest
integer).
12
102 The weight of gold formed when 1 faraday of electricity is passed through water solution of gold (III) chloride is :
A. One gram atom of Au
B. 2 gram atom of Au
c. 3 gram atom of Au
D. ( 1 / 3 ) gram atom of Au
12
103 Consider the cell;
( boldsymbol{V}^{2+}+boldsymbol{V} boldsymbol{O}^{2+}+boldsymbol{2} boldsymbol{H}^{+} rightarrow boldsymbol{2} boldsymbol{V}^{3+}+ )
( boldsymbol{H}_{2} boldsymbol{O} ; boldsymbol{E}^{o}=mathbf{0 . 6 1 6} boldsymbol{V} )
( boldsymbol{V}^{3+}+boldsymbol{A} boldsymbol{g}^{+}+boldsymbol{H}_{2} boldsymbol{O} rightarrow boldsymbol{V} boldsymbol{O}^{2+}+ )
( mathbf{2} boldsymbol{H}^{+}+boldsymbol{A} boldsymbol{g} ; boldsymbol{E}^{o}=mathbf{0 . 4 3 9} boldsymbol{V} )
Potential of ( boldsymbol{E}_{boldsymbol{V}^{3+} / boldsymbol{V}^{2+}}^{boldsymbol{o}} ) is :
(Given that ( left.boldsymbol{E}_{A g^{+} / A g}^{o}=mathbf{0 . 7 9 9} boldsymbol{V}right) )
A. ( -0.256 V )
( v )
B. ( 0.256 mathrm{V} )
c. ( 1.055 V )
D. ( 0.177 V )
12
104 A quantity of electrical charge that brings about the deposition of ( 4.5 g A l )
from ( A l^{3+} ) at the cathode will also
produce the following volume at ( (boldsymbol{S T P}) )
of ( boldsymbol{H}_{2}(boldsymbol{g}) ) from ( boldsymbol{H}^{+} ) at the cathode
A . ( 44.8 L )
B. 22.4 L
c. ( 11.2 L )
D. ( 5.6 L )
12
105 The standard reduction potentials of ( C u^{2+} mid C u ) and ( C u^{2+} mid C u^{oplus} ) are 0.337 V
and ( 0.153 mathrm{V} ), respectively. The standard electrode potential of ( C u oplus mid C u ) half cell
is:
A . ( 0.184 mathrm{v} )
в. 0.827
c. ( 0.521 mathrm{v} )
D. 0.490
12
106 A ( 0.5 ~ M ) Na ( O H ) solution offers a
resistance of 31.6 ohm in a
conductivity cell at room temperature. What shall be the approximate molar conductance of this ( N a O H ) solution if
cell constant of the cell is ( 0.367 mathrm{cm}^{-1} ? )
A ( cdot 234 S mathrm{cm}^{2} ) mole ( ^{-1} )
B. ( 23.2 mathrm{S} mathrm{cm}^{2} ) mole ( ^{-1} )
c. ( 4645 S mathrm{cm}^{2} ) mole ( ^{-1} )
D. ( 5464 S mathrm{cm}^{2} ) mole ( ^{-1} )
12
107 A solution of ( 9.65 A ) flowing for 10 min
deposits ( 3.0 g ) of the metal which
is monovalent. The atomic mass of the
metal is :
A . 10
B. 50
c. 30
D. 96.5
12
108 toppr
Q Type your question
Fill in the blanks by choosing an appropriate option.
At a particular spot of an object made of
iron, ( (i) ) of iron to ferrous ion takes
place and that spot behaves as ( (i i) )
Electrons released at ( (i) ) spot move through the metal and ( $ 0 ) to another
spot on the metal and reduce oxygen in
presence of ( boldsymbol{H}^{+} . ) This spot behave as
(iiii). The ferrous ions are further
oxidised by atmospheric oxygen to ferric ions which come out as rust, ( (i v) ) and with further production of ( (v) ) ions.
( A cdot(i)- ) Oxidation
(ii)- Anode, (iii)-Cathode, (iv)( F e_{2} O_{3} cdot x H_{2} O,(v)-H y d r o g e n )
B. (i)- Reduction, (ii)-Cathode, (iii)-Anode, (iv)- ( F e_{3} O_{4},(v) )
Hydrogen
C . (i)-Oxidation, (ii)-Cathode, (iii)-Anode, (iv)( F e_{2} O_{3} x H_{2} O,(v)-H y d r o g e n )
D. (i)-Oxidation, (ii)-Anode, (iii)-Cathode, (iv)- ( F e_{2} O_{3} ) ( H_{2} O,(v) ) -Ferrous
12
109 The reduction potential at ( mathrm{pH}=14 ) for the ( boldsymbol{C u}^{2+} / boldsymbol{C u} ) couples is:
( left[mathrm{Given}, boldsymbol{E}_{boldsymbol{C u}^{2+} / boldsymbol{C u}}^{boldsymbol{o}}=right. )
( left.mathbf{0 . 3 4} boldsymbol{V} ; quad boldsymbol{K}_{s p} boldsymbol{C u}(boldsymbol{O H})_{2}=mathbf{1} times mathbf{1 0}^{-mathbf{1 9}}right] )
A . ( 0.34 mathrm{V} )
в. ( -0.34 mathrm{V} )
c. ( 0.22 V )
D. ( -0.22 V )
12
110 Sea water is a good conductor of electricity but distilled water is not because:
A. sea water contains mineral salts
B. distilled water contains mineral.
c. both A and B
D. none of the above
12
111 Calculate the cell EMF in mV for:
( boldsymbol{P t}left|boldsymbol{H}_{2}(boldsymbol{1} boldsymbol{a} boldsymbol{t m})right| boldsymbol{H} boldsymbol{C l}(boldsymbol{0} . boldsymbol{0} boldsymbol{1} boldsymbol{M})|boldsymbol{A} boldsymbol{g} C l(s)| boldsymbol{A} )
if ( Delta G_{t}^{o} ) values are at ( 25^{circ} mathrm{C} ) ( -109.56 frac{k J}{m o l} ) for ( A g C l(s) ) and
( -130.79 frac{k J}{m o l} ) for ( left(H^{+}+C l^{-}right)(a q) )
A ( .456 m V )
в. ( 654 m V )
c. ( 546 m V )
D. None of these
12
112 How much electricity in terms of Faraday is required to produce 40.0 g of
( A l ) from molten ( A l_{2} O_{3} ? )
A. 1 Faraday
B. 2 Faraday
c. 3.2 Faraday
D. 4.44 Faraday
12
113 The EMF of a cell corresponding to the reaction:
( boldsymbol{Z} boldsymbol{n}(boldsymbol{s})+boldsymbol{2} boldsymbol{H}^{oplus}(boldsymbol{a} boldsymbol{q}) rightarrow )
( Z n^{2+}(0.1 M)+H_{2}(g, 1 a t m) ) is ( 0.82 V )
( operatorname{at} 25^{circ} C )
The pH of the solution at the hydrogen electrode is:
( boldsymbol{E}_{Z n^{2+} mid boldsymbol{Z n}}^{ominus}=-mathbf{0 . 7 6} boldsymbol{V} )
( boldsymbol{E}_{boldsymbol{H}^{ominus} mid boldsymbol{H}_{2}}^{Theta}=mathbf{0} )
If the value is ( 63 times 10-x ), then what is
the value of ( x ? )
12
114 The passage of electricity in the Daniell cell when ( mathrm{Zn} ) and ( mathrm{Cu} ) electrodes are
connected:
A. from Cu to Zn inside the cell
B. from Cu to Zn outiside the cell
c. from zn to Cu outside the cell
D. none of the above
12
115 The chemical effect produced by an electric current depends on:
A. the nature of electrode
B. the tester
c. the conducting solution
D. none of the above
12
116 In a Daniel cell when ( C u ) and ( Z n )
electrodes are connected current flows
from:
A. ( C u ) to ( Z n ) within the cell
B. ( C u ) to ( Z n ) outside the cell
c. ( Z n ) to ( C u ) outside the cell
D. all of the above
12
117 Alloy formation gives rise to:
A. decrease in corrosion
B. increase in hardness
C . decrease in conductivity
D. All are correct
12
118 State True or False.
It is not necessary that both oxidation and reduction should takes place in the
same redox reaction.
A. True
B. False
12
119 When electricity is passed through
molten ( A l C l_{3}, 13.5 g ) of ( A l ) is deposited. The number of Faraday’s must be:
A . 0.5
в. 1.0
c. 1.5
D. 2.0
12
120 ( boldsymbol{C u}left|boldsymbol{C u}^{+2}(mathbf{1} boldsymbol{M})right|left|boldsymbol{Z} boldsymbol{n}^{+2}(mathbf{1} boldsymbol{M})right| boldsymbol{Z} boldsymbol{n} )
A cell represented above should have
emf:
A. positive
B. negative
c. zero
D. cannot be predicted
12
121 Which are true for a standard hydrogen
electrode?
This question has multiple correct options
A. The hydrogen ion concentration is 1 m
B. Temperature is ( 25^{circ} mathrm{C} )
c. Pressure of hydrogen is 1 bar
D. It contains a metallic conductor which does not absorb hydrogen
12
122 Question 11. How will the pH of brine (aq. NaCl solution) be affected
when it is electrolysed?
12
123 Selenium has the unusual property of being a good conductor in light but a poor conductor in the dark. It was,
therefore, used in making.
A. Shaded glass
B. Photo-electric cells
c. Photo chemical celles
D. Chromatic lenses
12
124 The standard reduction potential for ( C u^{2+} / C u ) is +0.34 V. What will be the
reduction potential at ( mathrm{pH}=14 ?[ ) Given:
( left.boldsymbol{K}_{s p} text { of } boldsymbol{C u}(boldsymbol{O H})_{2} text { is } mathbf{1 . 0} times mathbf{1 0}^{-mathbf{1 9}}right] )
A . ( 2.2 v )
в. 3.4v
c. ( -0.22 v )
D . ( -2.2 v )
12
125 From the standard potential in acidic medium as shown in the following la-
timer diagram, the value of ( left(boldsymbol{E}_{1}^{mathbf{0}}+boldsymbol{E}_{2}^{0}right) )
in volts is:
12
126 ( boldsymbol{P t}left|boldsymbol{O}_{2}(boldsymbol{g}, boldsymbol{1} boldsymbol{a} boldsymbol{t m})right| boldsymbol{O} boldsymbol{H}^{-}(boldsymbol{1} boldsymbol{M}) | boldsymbol{C l}^{-}(boldsymbol{1} boldsymbol{M}) mid )
For the given cell, the cell reaction is:
12
127 During the discharge of a lead storage battery, the density of sulphuric acid
fell from 1.294 to ( 1.139 g m L^{-1} . H_{2} S O_{4} ) of
density ( 1.294 g m L^{-1} ) is ( 39 % ) and that of
density ( 1.139 g m L^{-1} ) is ( 20 % )
by weight.The battery holds 3.5 L of acid and the volume practically remains constant during discharge. The number of ampere hours for which the battery must have been used are..

The discharging and charging reactions
are:
( boldsymbol{P b}+boldsymbol{S O}_{4}^{2-} rightarrow boldsymbol{P b S O}_{4}+boldsymbol{2} boldsymbol{e}^{-} )
(charging) ( boldsymbol{P b O}_{2}+mathbf{4 H}^{+}+boldsymbol{S O}_{4}^{2-}+boldsymbol{2 e}^{-} rightarrow )
( P b S O_{4}+2 H_{2} O ) (discharging)

12
128 toppr ( t )
Q Type your question
( A )
( B )
( c )
( D )
12
129 0.3 Which of the following statement is correct?
(a) Ecell and A, G of cell reaction both are extensive properties
(b) Ecell and A, G of cell reaction both are intensive properties
(c) Ecell is an intensive property while A.G of cell reaction is an extensive property
(d) Ecell is an extensive property while A,G of cell reaction is an intensive property
Thinking Process
This problem is based on thermodynamical concept of intensive and extensive property
During answering this question must keep in mind that intensive property is
independent on number of particles and extensive property is dependent on number of
particles.
12
130 Consider the cell:
( boldsymbol{A} boldsymbol{g}(boldsymbol{s}), boldsymbol{A} boldsymbol{g} boldsymbol{C l}(boldsymbol{s})|boldsymbol{K} boldsymbol{C l}(boldsymbol{0} cdot mathbf{1} boldsymbol{M})| boldsymbol{H} boldsymbol{g}_{2} boldsymbol{C l}_{2}(boldsymbol{s}) )
The cell potential
This question has multiple correct options
A . increases on increasing concentration of ( C l^{-} ) ions
B. decreases on decreasing concentration of ( C l^{-} ) ions
c. is independent of concentration of ( C l^{-} ) ions.
D. is independent of amounts of ( A g C l ) and ( H g_{2} C l )
12
131 At ( 25^{circ} mathrm{C} ), the molar conductances at
infinite dilution for the strong
electrolytes ( N a O H, N a C l ) and ( B a C l_{2} )
( operatorname{are} 248 times 10^{-4}, 126 times 10^{-4} ) and ( 280 times )
( 10^{-4} S m^{2} m o l^{-1} ) respectively.
( wedge_{m}^{circ} B a(O H)_{2} ) in ( S m^{2} m o l^{-1} ) is :
A. ( 52.4 times 10^{-4} )
В. ( 524 times 10^{-4} )
c. ( 402 times 10^{-4} )
( mathbf{D} cdot 262 times 10^{-4} )
12
132 Question 3. Depict the galvanic cell in which the reaction,
Zn(s) + 2Ag* (aq) → Zn2+ (aq) + 2Ag(s) takes place. Further show:
i) Which of the electrode is negatively charged?
(ü) The carriers of the current in the cell.
(iii) Individual reaction at each electrode.
Anode is negative electrode and cathode is positive electrode. Anode is
always the site of oxidation and cathode is the site of reduction. In a
galvanic cell. anode half-cell is written on the left and cathode half-cell on
right. Salt bridge is represented as (parallel lines).
12
133 Among ( N a, H g, S, P t ) and graphite, which can be used as electrodes in
electrolytic cells having aqueous solutions?
A. ( H g ) and ( P t )
в. ( H g, P t ) and graphite
c. ( N a ) and ( S )
D. ( N a, H g ) and ( S )
12
134 The reaction,
[
begin{array}{c}
(mathbf{1} / mathbf{2}) boldsymbol{H}_{mathbf{2}}(boldsymbol{g})+boldsymbol{A} boldsymbol{g} boldsymbol{C} boldsymbol{l}(boldsymbol{s})= \
boldsymbol{H}+(boldsymbol{a} boldsymbol{q})+boldsymbol{C} boldsymbol{l}^{-}(boldsymbol{a} boldsymbol{q})+boldsymbol{A} boldsymbol{g}(boldsymbol{s}) text { occurs in }
end{array}
]
the galvanic cell
The correct cell representation is given
by
( mathbf{A} cdot A g|A g C l(s)| K C l(s o l n .)left|A g N O_{3}(s o l n .)right| A g )
B ( cdot P tleft|H_{2}(g)right| H C l(text {soln.}) mid A g N O_{3}(text {soln.}) mid A g )
( mathbf{c} cdot P tleft|H_{2}(g)right| H C l(s o l n .)|A g C l(s)| A g(s) )
D ( cdot P tleft|H_{2}(g)right| K C l(s o l n .)|A g C l(s)| A g )
12
135 The amount of ion discharged during electrolysis is not directly proportional
to
A . resistance
B. time
c. current
D. chemical equivalent of ion
12
136 A cell contains two hydrogen electrodes. The negative electrode is in
contact with a solution of ( 10^{-6} mathrm{M} )
hydrogen ions. The ( E M F ) of the cell is
( 0.118 V ) at ( 25^{circ} C . ) The concentration of
hydrogen ions at the positive electrode is:
A ( cdot 10^{-4} M )
В. ( 10^{-3} M )
( mathrm{c} cdot 10^{-1} M )
D. None of these
12
137 Which of the following is free of salts?
A. Distilled water
B. Sea water
c. tap water
D. All of the above
12
138 The efficiency of fuel cell is given by the
expression, ( eta ) is:
A ( quad eta=-frac{n F E_{c l l}}{Delta H} times 100 )
B. ( eta=-frac{n F E_{c l l l}}{Delta S} times 100 )
c. ( _{eta}=-frac{n F E_{c l l}}{Delta A} times 100 )
D. None of the above
12
139 0.30 Under what condition is E cell = 0 or A, G = 0 ? 12
140 For how long current of ( 3 mathrm{A} ) has to passed through ( A g N O_{3} ) solution to coat a
metal surface of ( 80 mathrm{cm}^{2} ) area and
thickness of ( 5 times 10^{-4} c m . ) The density of
silver is ( 10.5 mathrm{gm} / mathrm{cm}^{3} )
12
141 When electric current passes through
the filaments of a bulb, it starts
emitting light due to :
A. heating effect of electric current.
B. magnetic effect of electric current.
c. chemical effect of electric current
D. lighting effect of electric current.
12
142 In the electrochemical cell shown above,
which of the following half-reactions
occurs at the anode?
( mathbf{A} cdot C u^{2+}+e rightarrow C u^{-} )
B ( cdot Z n(s) rightarrow Z n^{2+}+2 e )
( mathbf{c} cdot Z n^{2+}+2 e rightarrow Z n(s) )
( mathbf{D} cdot C u(s) rightarrow C u^{2+}+2 e )
E ( cdot C u^{2+}+2 e rightarrow C u(s) )
12
143 The e.m.f. of the cell begin{tabular}{l|c||c|c}
( boldsymbol{P t} boldsymbol{H}_{2} ) & ( boldsymbol{H O C N} ) & ( boldsymbol{A} boldsymbol{g}^{+} ) \
( boldsymbol{1} boldsymbol{a} boldsymbol{t m} ) & ( boldsymbol{1} . boldsymbol{3} times mathbf{1 0}^{-boldsymbol{3}} boldsymbol{M} ) & ( boldsymbol{0 . 8} boldsymbol{M} )
end{tabular} mid ( boldsymbol{A} boldsymbol{g}(s) ) is
( 0.982 mathrm{V} . ) The ( mathrm{K}_{a} ) for HOCN is :
( boldsymbol{A} boldsymbol{g}^{+}+boldsymbol{e} rightarrow boldsymbol{A} boldsymbol{g}(boldsymbol{s}) ; boldsymbol{E}^{o}=mathbf{0 . 8 0} boldsymbol{V} )
A. ( 3.33 times 10^{-4} )
B . ( 2.22 times 10^{-4} )
c. ( 4.44 times 10^{-4} )
D. ( 1.6 times 10^{-3} )
12
144 Question 13. Write the chemistry of recharging the lead storage battery,
highlighting all the materials that are involved during recharging.
Recall the reactions during use of battery and reverse them.
12
145 5th Question 23. Consider the following diagram and answer the questions
Pe 6) to (vi) given below.
(1) Redraw the diagram to show the direction of electron flow.
Salt bridge
Zinc plate
Silver plate
Ag+ (aq)
Zn2+ (aq) 1
(ii) Is silver plate the anode or cathode?
(iii) What will happen if salt bridge is removed
(iv) When will the cell stop functioning
(v) How will concentration of Znions and Agt ions be affected
when the cell functions?
(vi) How will the concentration of Zn²+ ions and Agions be affected
after the cell becomes ‘dead’?
12
146 Q15. Define EMF of cell. 12
147 Construct the cells in which the
following reactions are taking place. Which of the electrodes shall act as
anode (negative electrode) and which one as cathode (positive electrode)?
(a) ( Z n+C u S O_{4}=Z n S O_{4}+C u )
(b) ( boldsymbol{C u}+mathbf{2 A g} boldsymbol{N O}_{3}=boldsymbol{C u}left(boldsymbol{N O}_{3}right)_{2}+ )
( mathbf{2} boldsymbol{A} boldsymbol{g} )
( (c) Z n+H_{2} S O_{4}=Z n S O_{4}+H_{2} )
(d) ( boldsymbol{F} boldsymbol{e}+boldsymbol{S} boldsymbol{n} boldsymbol{C l}_{2}=boldsymbol{F} boldsymbol{e} boldsymbol{C l}_{2}+boldsymbol{S} boldsymbol{n} )
12
148 Which of the following solution will not make the bulb glow?
A. Copper sulphate
B. Sodium chromate
c. Potassium dichromate
D. Sugar
12
149 The conductivity of N/10 KCl solution at
( 20^{circ} mathrm{C} ) is ( 0.0212 mathrm{Scm}^{-1} ) and the
resistance of cell containing this
solution at ( 20^{circ} C ) is 55 ohm. The cell
constant is:
A ( .2 .173 mathrm{cm}^{-1} )
B. ( 1.166 mathrm{cm}^{-1} )
c. ( 4.616 mathrm{cm}^{-1} )
D. ( 3.324 c m^{-1} )
12
150 On passing one faraday of electricity through a dilute solution of an acid, the
volume of hydrogen obtained at NTP
is
A. ( 22400 m L )
B. ( 1120 m L )
c. ( 2240 m L )
D. ( 11200 m L )
12
151 What is the chemical formula of rust? 12
152 44 which reference electrode is used to measure the electrode potential of
other electrodes?
12
153 If ( boldsymbol{E}^{o}_{boldsymbol{F} e^{2+} / boldsymbol{F} e}=boldsymbol{x}_{1} boldsymbol{V} ) and ( boldsymbol{E}^{o}_{boldsymbol{F} e^{3+} / boldsymbol{F} e^{2+}}= )
( boldsymbol{x}_{2} boldsymbol{V}, ) then ( boldsymbol{E}^{o} boldsymbol{F e}^{3+} / boldsymbol{F} e ) will be :
A ( cdotleft(2 x_{1}+x_{2}right) V )
В . ( left(3 x_{2}-x_{1}right) V )
( mathbf{c} cdotleft(2 x_{1}+x_{2}right) / 3 V )
( mathbf{D} cdotleft(x_{1}+2 x_{2}right) / 3 V )
12
154 The electrochemical cell stops working
after some time because:
A. electrode potentials of both electrodes becomes zero
B. electrode potentials of both electrodes becomes equal
C. temperature of the cell increases
D. the reaction starts proceeding in opposite direction
12
155 What is the electric current required to deposit 0.972 g of chromium in three hours?
(E.C.E. of chromium is 0.00018 g/c)
A . ( 0.50 A )
B. 1A
c. zero
D. 2.5A
12
156 Most liquids that conduct electricity are solutions of :
A . acids
B. bases
c. salts
D. all of the above
12
157 The Kohlrausch law is realted to:
A. Conductance of ions at infinite dilution
B. Independent migration of ions
C. Both (a) and (b)
D. neither
(a) and (b)
12
158 Iron rod is immersed in ( K C l K C l )
solution such that half its length is exposed to air and the other half
immersed in ( K C l K C l ) solution. The
part corroded faster is
12
159 The capacity of cell is measured in:
A. amperes
B. ampere-hour
c. watts
D. watt-hours
12
160 Calculate the e.m.f of the following cell reaction at ( 298 K: )
( boldsymbol{M} boldsymbol{g}_{(s)}+boldsymbol{C u}^{2+}(mathbf{0 . 0 0 0 1 M}) rightarrow )
( M g^{2+}(0.001 M)+C u_{(s)} )
The standard potential ( left(boldsymbol{E}^{o}right) ) of teh cell
is ( 2.71 V )
12
161 EMF of the cell
( Z nleft|Z n S O_{4}(a=0.2)right|left|Z n S O_{4}left(a_{2}right)right| Z n )
is ( -0.0088 mathrm{V} ) at ( 25^{circ} mathrm{C} ). Calculate the
value of ( a_{2} )
A ( cdot a_{2}=0.1006 mathrm{M} )
В . ( a_{2}=0.2012 M )
( mathbf{c} cdot a_{2}=0.3018 M )
D. None of these
12
162 ( M g^{2+}+2 e^{-} rightarrow M g ; E_{c e l l}^{circ}(V)=-2.37 )
( boldsymbol{C u}^{2+}+mathbf{2} e^{-} rightarrow boldsymbol{C u} ; boldsymbol{E}_{c e l l}^{circ}=mathbf{0 . 3 4} )
Analyze the data above.
Which substance should be used for
electrode B in this galvanic cell?
A ( cdot M g^{2} )
в. ( M g )
( c cdot C u^{2} )
D. ( C_{7} )
12
163 Chemical compounds which conduct electricity in the fused or in aqueous solution state and undergo chemical decomposition due to the flow of
current through it are known as:
A. electrolytes
B. non-electrolytes
c. weak electrolytes
D. all of the above
12
164 The fraction of the total current carried
by an ion is known as:
A. transport number of that ion
B. conductance of that ion
c. both (A) and (B)
D. none of the above
12
165 Which of the following reactions occur
at the cathode during the charging of
lead storage battery?
( mathbf{A} cdot P b^{2+}+2 e^{-} rightarrow P b )
B ( cdot P b^{2+}+S O_{4}^{2-} rightarrow P b S O_{4} )
( mathbf{c} cdot P b rightarrow P b^{2+}+2 e^{-} )
D ( cdot P b S O_{4}+2 H_{2} O rightarrow P b O_{2}+4 H^{+}+S O_{4}^{2-}+2 e^{-} )
12
166 The density and eq. wt. of a metal are ( 10.5 g c m^{-3} ) and ( 100, ) respectively. The
time required for a current of 3 amp to deposit a 0.005 mm thick layer of the
same metal on an area of ( 80 mathrm{cm}^{2} ) is
closest to:
( mathbf{A} cdot 120 s )
B. 135 s
c. ( 67.5 s )
D. 270 ( s )
12
167 At ( 25^{circ} C lambda_{infty}left(H^{+}right)=3.4982 times )
( 10^{-2} S m^{2-1} lambda_{infty}left(O H^{-}right)=1.98 times )
( 10^{-2} mathrm{Sm}^{2-1} )
Given: Sp. conductance ( =mathbf{5 . 1} times )
( 10^{-6} S m^{-1} ) for ( H_{2} O, ) determine ( p H ) and
( boldsymbol{K}_{boldsymbol{w}} )
12
168 The value of equilibrium constant for a
feasible cell reaction is:
( mathbf{A} cdot1 )
D. zero
12
169 Iron nails rust fast when used for fixing plates or strips of aluminium on a building. Similarly, a water pipe made of iron corrodes faster when connected
to a pipe of copper. This happens because of the?
A. Greater wetting of iron
B. Easier flow of electrons to iron
c. Higher rusting power of iron
D. Chemical reduction of iron
12
170 In following cell reaction
( M g(s)+2 A g^{+}(0.001 M) rightarrow )
( M g^{2+}(0.20 M)+2 A g(s) )
Calculate ( E_{text {cell}} ) for the reaction ( left[E^{o}=right. ) ( left.mathbf{3 . 1 7} boldsymbol{V}, frac{mathbf{2 . 3 0} boldsymbol{R} boldsymbol{T}}{boldsymbol{F}}=mathbf{0 . 0 5 4}right] )
( A cdot 2.63 V )
B. 3.01V
c. ( 3.33 v )
D. 3.51V
12
171 Why does anode material have good
hydrogen storage capacity for a Nickelmetal hydride battery?
12
172 0.39 How will the pH of brine (aq NaCl solution) be affected when it is
electrolysed?
12
173 ( C u^{2+}+2 e^{-} rightarrow C u )
( boldsymbol{E}_{text {red}} boldsymbol{v s} cdot log left[boldsymbol{C u}^{2+}right] ) graph is of the type
as shown in figure where ( O A=0.34 V )
then electrode potential of the half cell of ( C u mid C u^{2+}(0.1 M) ) will be :
A. ( _{-0.34}+frac{0.0591}{2} mathrm{V} )
В. ( 0.34+0.0591 V )
( c .0 .34 V )
D. none of thes
12
174 ( boldsymbol{N} boldsymbol{i}left|boldsymbol{N} boldsymbol{i}^{2+}(boldsymbol{1} . boldsymbol{0} boldsymbol{M}) | boldsymbol{A} boldsymbol{u}^{3+}(mathbf{1} . boldsymbol{0} boldsymbol{M})right| boldsymbol{A} boldsymbol{u} )
(where ( boldsymbol{E}^{o} ) for ( boldsymbol{N} boldsymbol{i}^{2+} / boldsymbol{N} boldsymbol{i} ) is ( -mathbf{0 . 2 5} ) and ( boldsymbol{V} )
and ( E^{o} ) for ( A u^{3+} / A u ) is ( 0.150 V ) ). What
is the emf of the cell?
A ( .+0.4 V )
в. ( -1.75 V )
( mathrm{c} .+1.25 mathrm{V} )
D. ( +1.75 V )
12
175 The reaction
( mathbf{1} / mathbf{2} boldsymbol{H}_{mathbf{2}}(boldsymbol{g})+boldsymbol{A} boldsymbol{g} boldsymbol{C l}(boldsymbol{s}) rightarrow boldsymbol{H}^{oplus}(boldsymbol{a} boldsymbol{q})+ )
( boldsymbol{C l}^{ominus}(boldsymbol{a q})+boldsymbol{A} boldsymbol{g}(boldsymbol{s}) ) occurs in the
galvanic cell:
A ( cdot A g|A g C l(s)| K C l(s o l)left|A g N O_{3}right| A g )
B . ( P tleft|H_{2}(g)right| H C l(s o l)left|A g N O_{3}(s o l)right| A g )
c. ( P tleft|H_{2}(g)right| H C l(s o l)|A g C l(s)| A g )
D. ( P tleft|H_{2}(g)right| K C l(s o l)|A g C l(s)| A g )
12
176 The standard reduction potential
values, ( boldsymbol{E}^{circ}left(boldsymbol{B} boldsymbol{i}^{3+} / boldsymbol{B} boldsymbol{i}right) ) and
( E^{circ}left(C u^{2+} / C uright) ) are ( 0.226 mathrm{V} ) and ( 0.344 mathrm{V} )
respectively. A mixture of salts of bismuth and copper at unit
concentration each is electrolysed at
( 25^{circ} mathrm{C} . ) To what value ( operatorname{can}left[C u^{2+}right] ) be
brought down before bismuth starts to
deposit, in electrolysis.
( mathbf{A} cdotleft[C u^{2+}right]=10^{-8} M )
B. ( left[C u^{2+}right]=10^{-4} M )
( mathbf{C} cdotleft[C u^{2+}right]=10^{-3} M )
D. ( left[C u^{2+}right]=10^{-6} M )
12
177 For a cell reaction involving a two-electron change, the standard emf of the cell is found to be ( 0.295 mathrm{V} ) at ( 25^{circ} mathrm{C} ). The
equilibrium constant of the reaction at
( 25^{circ} mathrm{C} ) will be :
A ( cdot 1 times 10^{-10} )
B . ( 29.5 times 10^{-2} )
c. 10
D. ( 1 times 10^{10} )
12
178 The potential of hydrogen electrode having a solution of ( mathrm{pH}=4 ) at ( 298 mathrm{K} ) is:
A. ( -0.177 V )
B. ( -0.236 V )
c. ( 0.177 V )
D. ( 0.236 V )
12
179 The cell constant of a given cell is ( 0.47 mathrm{cm}^{-1} . ) The resistance of a solution
placed in this cell is measured to be
31.6 ohm. The conductivity of the
solution ( left(text { in } S c m^{-1} text {where } S ) has usual right.
meaning) is :
A . 0.15
в. 1.5
c. 0.015
D. 150
12
180 What will be the reduction potential for the following half-cell reaction at ( 298 mathrm{K} ? )
(Given: ( left[boldsymbol{A} boldsymbol{g}^{+}right]=mathbf{0 . 1} mathbf{M} ) and ( boldsymbol{E}_{c e l l}^{o}=+mathbf{0 . 8 0} )
( mathbf{V}) )
A . ( 0.741 mathrm{v} )
B. ( 0.80 v )
c. ( -0.80 v )
D. ( -0.741 mathrm{V} )
12
181 Assertion
When an electric current is passed through an aqueous solution of sodium chloride, sodium ions move towards cathode and chloride ions move towards
anode.
Reason
Cathode is a negatively charged electrode and therefore attracts ( mathrm{Na}^{+} )
ions. Anode is a positively charged
electrode and therefore attracts ( mathrm{Cl}^{-} )
ions.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
182 An electrolysis of a oxytungsten complex ion using ( 1.10 A ) for 40 min produces ( 0.838 g ) of tungsten. What is the charge of tungsten in the material? (Atomic weight: ( boldsymbol{W}=mathbf{1 8 4} ) )
A . 6
B. 3
( c .5 )
D.
12
183 Which of the following reaction is used
to make a fuel cell?
( mathbf{A} cdot C d(s)+2 N i(O H)_{3}(s)+H_{2} O(l) longrightarrow C d O(s)+ )
[
2 N i(O H)_{3}(s)+H_{2}(g)
]
B ( .2 mathrm{Fe}(s)+mathrm{O}_{2}(g)+4 H^{+}(a q) longrightarrow 2 mathrm{Fe}^{2+}(a q)+2 mathrm{H}_{2} mathrm{O}(l) )
( mathbf{c} cdot P b(s)+P b O_{2}(g)+2 H_{2} S O_{4}(a q) longrightarrow 2 P b S O_{4}(s)+ )
( 2 H_{2} O(l) )
D. ( 2 H_{2}(g)+O_{2}(g) longrightarrow 2 H_{2} O(l) )
12
184 Water obtained from which of the
following sources is a good conductor of electricity?
A . Tap
B. Ponds
c. wells
D. All of the above
12
185 In voltaic cell, oxidation takes place at:
A . positive electrode
B. negative electrode
c. cathode
D. none of the above
12
186 Observe the following picture and
answer the following question:
What is corrosion?
12
187 Which of the following is used to detect
the current?
A . Tester
B. LED
c. compass needle
D. All of the above
12
188 Some oils and fats give a bad smell and taste because of
A. rancidity
B. decomposition reaction
c. hydrogenation reaction
D. double displacement reaction
12
189 A standard hydrogen electrode has zero electrode potential because:
A. hydrogen is easiest to oxidise
B. this electrode potential is assumed to be zero
c. hydrogen atom has only one electron
D. hydrogen is the lightest element
12
190 What is a cathode?
A. Electrode where reduction takes place and electrons are gained.
B. Electrode where oxidation takes place and electrons are lost.
C. Electrode where reduction takes place and electrons are lost.
D. A fluid that conducts electricity.
E. Electrode where oxidation takes place and electrons a re gained.
12
191 The products obtained at cathode and anode on electrolysis of aqueous sodium succinate are :
A. anode: ethene ( +C O_{2} ), cathode : ( H_{2} )
B. anode: ethyne ( +C O_{2} ), cathode : ( H_{2} )
c. anode : ethyne + ( H_{2} ), cathode : Na
D. anode: ethyne ( +C O_{2} ), cathode : Na
12
192 What weight of zinc will get deposited?
A . 65.3 g
B. 0.33 mg
c. 0.438 g
D. 42.3 ( g )
12
193 Which of the following is true for electrolytic refining?
A. Pure metal is used at anode and impure metal at cathode
B. Pure metal is used at cathode and impure metal at anode
c. Both can be possible A and B
D. None of these
12
194 State True or False.
The redox reaction involved in galvanic
cell is a non-spontaneous process.
A. True
B. False
12
195 If the molar conductivities (in ( mathrm{S} mathrm{cm}^{2} )
( mathrm{mol}^{-1} ) ) of ( mathrm{NaCl} ), ( mathrm{KCl} ) and ( mathrm{NaOH} ) at infinite
dilution are 126,150 and 250
respectively, the molar conductivity of KOH is:
( left[operatorname{in} mathrm{S} mathrm{cm}^{2} mathrm{mol}^{-1}right] )
A .526
в. 226
c. 26
D. 274
12
196 Assertion: In a Daniell cell, electrons
flow from zinc electrode to copper
electrode outside the cell.
Reason: In Daniell cell, Zn electrode is
anode and Cu is cathode.
A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c. Assertion is true but Reason is false
D. Assertion is false but Reason is true
E. Both Assertion and Reason are false
12
197 Pieces of copper, silver and gold are dropped into a solution of iron sulphate. The piece that will get a coating of
copper is:
( A ). iron
B. silver
c. gold
D. None of them
12
198 How many grams of copper will be
deposited from a solution of ( C u S O_{4} )
bypassing 0.5 faradays of electricity? [Atomic weight of ( boldsymbol{C u}=mathbf{6 3 . 5} text { g/mole }] )
A. ( 31.75 mathrm{g} )
B. 63.6 g
c. ( 15.875 mathrm{g} )
D. 127 g
12
199 Electricity can be obtained by oxidation-reduction reaction in voltaic
cell.
A. True
B. False
12
200 . 36 Consider the following diagram in which an electrochemical cell is
coupled to an electrolytic cell. What will be the polarity of electrodes A
and ‘B’ in the electrolytic cell?
Salt bridge
6) Tlr
Zince
Copper plate
plate
Solution
Znso.
-Cuso.
(B) Electrode
(A) Electrode
Electrolytic
cell
12
201 For a given reaction:
( boldsymbol{F} boldsymbol{e}+boldsymbol{2} boldsymbol{F} boldsymbol{e}^{boldsymbol{3}+} rightarrow boldsymbol{3} boldsymbol{F} boldsymbol{e}^{boldsymbol{2}+} )
12
202 ( E^{o} ) of an electrode half reaction is
related to ( Delta G^{o} ) by the equation, ( E^{o}= )
( -Delta G^{o} / n F . ) If the amount of ( A g^{+} ) in the
half reaction ( boldsymbol{A} boldsymbol{g}^{+}+boldsymbol{e}^{-} rightarrow boldsymbol{A} boldsymbol{g} ) is tripled
then:
A . n is tripled
B. ( Delta G^{o} ) increases to three times
c. ( E^{o} ) reduces to one third
D. All the above
12
203 Calculate the number of coulombs
required to deposit 6.75 g of ( A l ) when the electrode reaction is:
( boldsymbol{A l}^{3+}+mathbf{3} e^{-} rightarrow boldsymbol{A l} )
12
204 How many moles of ( boldsymbol{P t} ) may be deposited on the cathode when ( 0.80 mathrm{F} ) of
electricity is passed through a ( 1.0 mathrm{M} )
solution of ( boldsymbol{P} boldsymbol{t}^{4+} ) ?
A. 0.1 mol
B. 0.2 mol
( c .0 .4 mathrm{mol} )
D. 0.6 mo
12
205 18. Standard electrode potential data are useful for
understanding the stability of an oxidant in redox
titration. Some half-cell reactions and their standard
potentials are given below:
MnO2 (aq) +8H+ (aq) +5e-
Mn2+ (aq) + 4H20 (0) Eº=1.51 V
Cryo- (aq) +14H+ (aq) + 6e —
2Cr3+ (aq) +7H2O(C) E° =1.38 V
Fe3+ (aq) +é – Fe2+ (aq) E° = + 0.77 V
Cl2(g) + 2e 2014 (aq) E° =1.40 V
Identify the only incorrect statement regarding the
quantitative estimation of aqueous Fe(NO2),
(a) MnO2 can be used in aqueous HCI
(b) Cr2O3 can be used in aqueous HCI
(c) MnOcan be used in aqueous H2SO4
(d) Cr2O2 can be used in aqueous H,SO
12
206 Assertion: Dry cell is a primary cell and
lead storage cell is a secondary cell Reason: A primary cell can only be used once while secondary cells are rechargeable.
A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c. Assertion is true but Reason is false
D. Assertion is false but Reason is true
E. Both Assertion and Reason are false
12
207 The conductivity of an electrolytic
solution decreases on dilution due to:
A. decrease in number of ions per unit volume
B. increase in ionic mobility of ions
C. increase in percentage ionisation
D. increase in number of ions per unit volume
12
208 Aluminium is more reactive than iron.
But aluminium is less easily corroded than iron because:
A. aluminium is a noble metal
B. oxygen forms a protective oxide layer on aluminium surface
C. iron unergoes reaction easily with water
D. iron forms both mono and divalent ions
12
209 Given :
Oxidation:
( H_{2} O_{2} rightarrow O_{2}+2 H^{oplus}+2 e^{-} )
( E^{ominus}=-0.69 V )
( 2 F^{ominus} rightarrow F_{2}+2 e^{-} )
( E^{ominus}=-2.87 V )
Reduction:
( H_{2} O_{2}+2 H^{oplus}+2 e^{-} rightarrow 2 H_{2} O )
( E^{ominus}=-1.77 V )
( 2 I^{ominus} rightarrow I_{2}+2 e^{-} E^{ominus}=-0.54 V )
Which of the following statements is/are
correct?
This question has multiple correct options
A ( cdot H_{2} O_{2} ) behaves as an oxidant for ( I^{ominus} )
B. ( H_{2} O_{2} ) behaves as a reductant for ( I_{2} )
C. ( H_{2} O_{2} ) behaves as an oxidant for ( F^{ominus} )
D. ( H_{2} O_{2} ) behaves as a reductant for ( F_{2} ).
12
210 Assertion
( mathrm{E}^{0} ) value of single electrode is determined experimentally by combining the electrode with SHE
Reason
SHE is taken as a reference electrode
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
211 The emf ( left(E^{circ}right) ) of the following cells are:
( boldsymbol{A} boldsymbol{g} / boldsymbol{A} boldsymbol{g}^{+}(mathbf{1} boldsymbol{M}) | )
( boldsymbol{C u}^{2+}(mathbf{1} boldsymbol{M}) mid boldsymbol{C u} ; boldsymbol{E}^{circ}=-mathbf{0 . 4 6} boldsymbol{v o l t} )
( boldsymbol{Z} boldsymbol{n} / boldsymbol{Z} boldsymbol{n}^{boldsymbol{2}+}(boldsymbol{1} boldsymbol{M}) | )
( boldsymbol{C u}^{2+}(mathbf{1} boldsymbol{M}) mid boldsymbol{C u} ; boldsymbol{E}^{circ}=+mathbf{1 . 1 0} boldsymbol{v o l t} )
Calculate the emf of the cell:
( boldsymbol{Z} boldsymbol{n}left|boldsymbol{Z} boldsymbol{n}^{2+}(boldsymbol{1} boldsymbol{M}) | boldsymbol{A} boldsymbol{g}^{+}(boldsymbol{1} boldsymbol{M})right| boldsymbol{A} boldsymbol{g} )
12
212 A conductivity cell has been calibrated
with a ( 0.01 M 1: 1 ) electrolyte solution
(specific conductance ( kappa=1.25 times )
( 10^{-3} mathrm{Scm}^{-1} ) ) in the cell and the
measure resistance was ( 800 Omega ) at ( 25^{circ} C )
The cell constant will be:
A ( cdot 1.02 mathrm{cm}^{-1} )
В. ( 0.102 c m^{-1} )
c. ( 1.00 mathrm{cm}^{-1} )
D. ( 0.5 mathrm{cm}^{-1} )
12
213 If the pressure of ( H_{2} ) gas is increased
from 1atm to 100atm keeping ( boldsymbol{H}^{+} ) concentration constant at ( 1 M, ) the
change in reduction potential of
hydrogen half cell at ( 25^{circ} C ) will be:
A. ( 0.059 V )
( V )
B . ( 0.59 V )
c. ( 0.0295 V )
D. ( 0.118 V )
12
214 How many spoons can be electroplated by silver when 7 ampere current is passed through electrolyte cell of ( A g N O_{3} ) for 1.93 hours? ( 0.01 g m A g )
layer is deposited on each spoon. ( left(A g=108 g cdot m o l^{-1}right) )
12
215 Select the correct statement(s) about
NHE.
This question has multiple correct options
( mathbf{A} cdot E^{ominus} ) of ( mathrm{NHE} ) is arbitrarilly assumed to be zero.
B. ( E^{ominus} ) of NHE is equal to zero.
( mathbf{C} cdot ) NHE refers as ( P t, H_{2}(g) mid H_{a=1}^{oplus}(a q) ) at ( 25^{circ} C )
D. NHE is very susceptible to dissolved ( O_{2}, H_{2} S ), and all other reducing agents.
12
216 Which of the following is correct
statement?
A. Conductivity & molar conductivity of solution increase on dilution
B. Voltage of button cell remain unchanged through out its life time
C. On electrolysis of aqueous ( C u S O_{4} ) using platinum
electrode its concentration ( left[C u^{2+}right] ) remain constant
D. On electrolysis of aqueous ( N a C l ), solution becomes acidic
12
217 Which of the following is incorrect in a galvanic cell?
A. Oxidation occurs at anode
B. Reduction occurs at cathode
c. The electrode at which electrons are gained is called cathode
D. The electrode at which electrons are lost is called cathode
12
218 How will you show that air and moisture both are required for rusting of iron? 12
219 For mercury at ( 0^{circ} mathrm{C} ) specific
conductance,
( boldsymbol{K}=mathbf{1 . 0 6 2 9 6 3} times mathbf{1 0}^{mathbf{6}} boldsymbol{S} / boldsymbol{m} )
(a) If the resistance of a cell containing mercury is 0.243166 ohm, What is the
cell constant of the cell?
(b) If the same cell is fixed with ( K C l )
solution at ( 0^{circ}, ) the resistance of the cell
is ( 3.966 times 10^{4} ) ohm. What is the
conductivity of ( K C l ) solution?
(c) If the average cross-sectional area of
the cell is ( 0.9643 m m^{2}, ) what is the
effective distance between the
electrodes?
12
220 (a) What type of battery is the lead storage battery? Write the anode and the cathode reactions and the overal
reaction occurring in a lead storage battery when current is drawn from it.
(b) In the button cell, widely used in watches, the following reaction taken place.
( Z n(s)+A g_{2} O(s)+H_{2} O(l) rightarrow )
( Z N^{2+}(a q)+2left(A g(s)+2 O H^{-}(a q)right. )
Determine ( E^{o} ) and ( Delta G^{o} ) for the reaction
(given: ( boldsymbol{E}_{boldsymbol{beta} boldsymbol{g}^{+} / boldsymbol{A} boldsymbol{g}}=+boldsymbol{0 . 8 0} boldsymbol{V}, boldsymbol{E}_{Z n^{2+} / Z n}^{o}= )
( -0.76 V) )
12
221 State True or False.
Corrosion of motor cars is the major problem in the winter, when salt is spread on road to melt ice and snow
A. True
B. False
12
222 Two Faraday of electricity is passed
through a solution of ( C u S O_{4} . ) The mass of copper deposited at the cathode is
at. mass of ( mathrm{Cu}=63.5 text { amu }) )
( A cdot O g )
в. ( 63.5 mathrm{g} )
( c cdot 2 g )
D. 127 g
12
223 Which of the following changes will cause the free energy of the cell reaction to decrease:
( boldsymbol{Z} boldsymbol{n}left|boldsymbol{Z n} boldsymbol{S} boldsymbol{O}_{4(boldsymbol{a q})}(boldsymbol{x}, boldsymbol{M}) | boldsymbol{H} boldsymbol{C l}_{(boldsymbol{a q})}left(boldsymbol{x}_{boldsymbol{2}} boldsymbol{M}right)right| boldsymbol{H} )
This question has multiple correct options
( 200 mathrm{m} )
B. Increase in pressure of hydrogen from 1 atm to 2 atm
c. Increase in molarity ( x_{2} ) from 0.1 to 1 M
D. Decrease in molarity ( x_{1} ) from 1 M to 0.1 M
12
224 How much ( O_{2} ) gas will be collected at
the anode at ( 300 K ) temperature and 1
bas pressure if 2.5 ampere electric
current is passed for one hour in electrolysis of aqueous solution of ( N a_{2} S O_{4} .(F=96500 text { Coulomb) }[1text { mole } )
gas volume is 22.4 litre at STP].
12
225 Assertion
The mobility of ( N a^{oplus} ) is lower than that
of ( boldsymbol{K}^{oplus} ) ion
Reason
The ionic mobility depends upon the effective radius of the ion.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
226 A piece granulated zinc was dropped into copper sulphate solution. After sometime the colour of the solution
changed from blue to colourless. Why?
12
227 When the electric current is passed
through a cell having an electrolyte, the positive ions move towards cathode and negative ions towards the anode. If the cathode is pulled out of the solution
then
A. the positive and negative ions will be move towards anode
B. the positive ions will start moving towards the anode and while negative ions will stop moving
c. the negative ions will continue to move towards and while positive ions will stop moving
D. the positive and negative ions will start moving random
12
228 Assertion
Lead storage battery is galvanic cell
without salt bridge.
Reason
A secondary cell is rechargeable cell.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
229 Electric circuit provides a complete
path for:
A. solution to flow
B. metal to flow
c. neutron to flow
D. current to flow
12
230 Which of the following is anodic
reaction:
( mathbf{A} cdot S O_{4}^{2-}+H_{2} O rightarrow H_{2} S O_{4}+1 / 2 O_{2}+2 e^{-} )
( mathbf{B} cdot H^{oplus}+e^{-} rightarrow 1 / 2 H_{2} )
( mathbf{C} cdot A g^{oplus}+e^{-} rightarrow A g )
D. None of above
12
231 State True or False.
The electrical energy released from an electrochemical cell can do useful work.
A. True
B. False
12
232 A current of 2 ampere passing for 5 hours deposits ( 22.2 mathrm{g} ) of tin, the oxidation state of tin is:
[At. wt. ( =119] )
A. 0
B. 3
( c cdot 2 )
D. 4
12
233 At ( p H=2, E_{Q u i n h y d r o n e} ) will be:
( left(E_{Q u i h y d r o n e}^{o}=1.30 Vright) )
A . ( 1.36 V )
B . ( 1.30 V )
c. ( 1.42 v )
D. ( 1.20 V )
12
234 The equilibrium constant for the
following reaction at ( 25^{circ} mathrm{C} ) is ( 2.9 times 10^{9} )
Calculate standard voltage of the cell.
( boldsymbol{C l}_{2(boldsymbol{g})}+boldsymbol{B r}_{(boldsymbol{a q})}^{-} rightleftharpoons boldsymbol{2} boldsymbol{C l}_{(boldsymbol{a q})}^{-} )
( mathbf{A} cdot 0.18 mathbf{V} )
B. ( 0.22 v )
c. ( 0.26 v )
D. ( 0.28 mathrm{v} )
12
235 Water is broken down into its
constituent elements …………. and
12
236 A method of protecting steel and iron from rusting is:
A. rusting
B. corrosion.
c. galvanisation.
D. sublimation
12
237 For the cell reaction ( : C u^{2+}(a q)left(C_{1}right)+ )
( Z n(s) rightarrow Z n^{2+}(a q)left(C_{2}right)+C u(s) ) the
change in free energy ( Delta G ) at a given temperature is a function of
( A cdot ln C_{1} )
в. ( ln left(frac{C_{2}}{C_{1}}right) )
( mathrm{c} cdot ln left(C_{2}+C_{2}right) )
D. ( ln left(C_{2}right) )
12
238 If ( x ) is the ratio of currents it takes to
produce 4.5 g of platinum from molten
( P t C l_{3} ) and ( P t C l_{5}, ) then ( 10 x )
is
Electrolysis in each case is carried out for ( 1 mathrm{min} 40 ) s. (Atomic Mass of ( mathrm{Pt}= )
195.0)
12
239 Passage of a current for 548 seconds
through a silver coulometer results in the deposition of ( 0.746 mathrm{g} ) of silver. What is the current (in A)?
A . 1.22
в. 1.16
c. 1.07
D. 1.00
12
240 ( boldsymbol{S}_{1} rightarrow ) Conductivity increases on decreasing concentration of electroyte
( boldsymbol{S}_{1} rightarrow ) Molar Conductivity increases on
decreasing concentration of electroyte
( A cdot S_{1} ) is true, ( S_{2} ) is False
B. Both ( S_{1} & S_{2} ) are true
c. Both ( S_{1} & S_{2} ) are false
D. ( S_{1} ) is false, ( S_{2} ) is true
12
241 Calculate the dissociation constant of
water at ( 25^{circ} mathrm{C} ) from the following data.
Specific conductance of ( boldsymbol{H}_{2} boldsymbol{O}=mathbf{5} . boldsymbol{8} times )
( 10^{-8} m h o c m^{-1},: lambda_{H^{+}}^{infty}=350.0 ) and
( lambda_{O H^{-}}^{infty}=198.0 m h o c m^{2} )
The ans is ( k times 10^{-16} ) mole/litre. find ( k )
A . 1.8
в. 100
( c . )
D. 0.01
12
242 During discharge of a lead storage cell, the density of sulphuric acid in the cell:
A. increases
B. decreases
c. remains unchanged
D. initially increases but decreases subsequently
12
243 If one mole electrons is passed through
the solutions of ( A l C l_{3}, A g N O_{3} ) and
( M g S O_{4}, ) in what ratio ( A l, A g ) and ( M g ) will be deposited at the electrodes?
A .3: 6: 2
B . 2: 6: 3
( mathrm{c} cdot 1: 2: 3 )
D. 3: 2: 1
12
244 In which of the following electrolysis,
electrodes act as active electrodes.
Electrolysis of:
A. fused NaCl between graphite electrodes
B. fused AgNO between platinum electrodes
C . aqueous AgNO solution between Ag electrodes
D. aqueous AgNO solution between pt electrodes
12
245 Calculate the potential of a half cell
having reaction: ( quad A g_{2} S(s)+2 e^{-} rightleftharpoons )
( 2 A g(s)+S^{2-}(a q) ) in a solution
buffered at ( p H=3 ) and which is also
saturated with ( 0.1 M H_{2} S(a q) )
( left[text { Given: } boldsymbol{K}_{s p}left(boldsymbol{A} boldsymbol{g}_{2} boldsymbol{S}right)=right. )
( mathbf{1 0}^{-49}, boldsymbol{K}_{boldsymbol{a}_{1}} cdot boldsymbol{K}_{boldsymbol{a}_{2}}=mathbf{1 0}^{-mathbf{2 1}} )
A . 1.18
B. 0.19
c. ( -0.19 V )
D. None of these
12
246 Iron and rust are the same things.
A. True
B. False
12
247 Explain two ways by which food industries prevent rancidity. Discuss the importance of decomposition reaction in metal industry with three points. 12
248 The process of lead action in a simple
voltaic cell
A. Catalyses the process of electrolysis
B. Increases the efficiency of the cell
c. Decreases the efficiency of the cell
D. Increases the charge carriers
12
249 Assertion: In the calomel half-cell, the
reduction reaction to be considered is
( mathrm{Hg}_{2} mathrm{Cl}_{2}(mathrm{s})+2 mathrm{e}^{-} rightarrow 2 mathrm{Hg}(mathrm{I})+2 mathrm{Cl}^{-}(mathrm{aq}) )
Reason: The Saturated calomel
electrode (SCE) is a reference electrode
based on the reaction between
elemental mercury and mercury(l) chloride
A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
C. Assertion is true but Reason is false
D. Assertion is false but Reason is true
E. Both Assertion and Reason are false
12
250 For the following reactions:
( Z n rightarrow Z n^{2+}+2 e^{-} ; E=+0.76 V )
( boldsymbol{A u} rightarrow boldsymbol{A u}^{3+}+mathbf{3} e^{-} ; boldsymbol{E}=-mathbf{1 . 4 2} boldsymbol{V} )
If gold foil is placed in a solution
containing ( Z n^{2+}, ) the reaction potential
would be:
A . ( -1.34 V )
в. ( -2.18 V )
c. ( -0.66 V )
D. ( +2.18 V )
E . ( +1.34 V )
12
251 ( Delta G_{f}^{o} ) (standard free energy of formation) of ( Z n O ) and ( C O ) are ( -318.2 mathrm{kJ} )
( mathrm{mol}^{-1} ) and ( -137.3 mathrm{kJ} mathrm{mol}^{-1} ) respectively.
( Z n O+C longrightarrow Z n+C O )
The approximate value of ( Delta G_{f}^{o} ) in kJmol
-1 for the above reaction is
( mathrm{kJ} mathrm{mol}^{-1} )
[Write your answer in form of inearest integer]
12
252 A sample of water from a large swimming pool has a resistance of ( 9200 Omega ) at 25 of NaCl wear dissolved in
the pool, which was throughly stirred. A sample of this solution gave a resistance at ( 7600 Omega ). calculate the
volume of water in the pool
Given: Molar conductor of NaCl at that
concentration is ( 126.5 Omega^{-1} c m^{2} m o l^{-1} )
and molar conductivity of KCl at ( 0.02 mathrm{M} ) is ( 138 Omega^{-1} c m^{2} ) mol ( ^{-1} ) and resist is 85
( Omega^{-1} )
12
253 During electrolysis of an aqueous
solution of sodium sulphate, 2.4 L of oxygen at STP was liberated at anode.
The volume of hydrogen at STP,
liberated at cathode would be:
A . 1.2
B. 2.4 L
c. 2.6
D. 4.8 L
12
254 Effect of temperature on internal
resistance of a battery is:
A. directly proportional
B. inversely proportional
c. no effect
D. none of these
12
255 Which is correct about the reaction
between ( H_{2} O ) and ( O_{2} ? )
( mathbf{A} cdot ) It is a case of mutual reduction
B. ( O_{3} ) will oxidize ( H_{2} O_{2} ) into ( O_{2} )
C. It is not a redox reaction
D. ( H_{2} O_{2} ) being a stronger oxidizing agent will decompose ozone into oxygen
12
256 ( boldsymbol{E}^{0}left(boldsymbol{N} boldsymbol{i}^{2+} / boldsymbol{N} boldsymbol{i}right)= )
( -0.25 v o l t, E^{0}left(A u^{3+} / A uright)=1.50 v o l t )
The standard emf of the voltaic cell.
( boldsymbol{N} boldsymbol{i}_{(s)}left|boldsymbol{N} boldsymbol{i}_{(a q)}^{2+}(mathbf{1} . boldsymbol{0} boldsymbol{M}) | boldsymbol{A} boldsymbol{u}_{(a q)}^{3+}(mathbf{1} . boldsymbol{0} boldsymbol{M})right| boldsymbol{A} boldsymbol{u}_{(s)} )
is:
A. 1.25 volt
B . – 1.75 volt
c. 1.75 volt
D. 4.0 volt
12
257 Which of these metals do not corrode?
A. Lead
B. copper
C. Platinum
D. Silver
12
258 acts as the
cathode.
( mathbf{A} cdot Z n(s) )
B. ( C u^{2+}(a q) )
( mathbf{c} cdot Z n^{2+}(a q) )
( mathbf{D} cdot C u(s) )
E ( . H_{2} O )
12
259 How much electricity in terms of Faraday is required to produce:
(i) ( 20 g ) of ( C a ) from molten ( C a C l_{2} )
(ii) ( 40 g ) of ( A l ) from molten ( A l_{2} O_{3} )
[Given : Molar mass of calcium &
Aluminium are 40 g ( m o l^{-1} & 27 g ) mol ( left.^{-1} text {respectively }right] )
12
260 Which Nernst equation is true to find
out the potential of non-standard
electrochemical cell from the following?
( boldsymbol{F} boldsymbol{e}(boldsymbol{s})left|boldsymbol{F} boldsymbol{e}^{2+}(boldsymbol{x} boldsymbol{M}) | boldsymbol{I}^{-}(boldsymbol{a} boldsymbol{q} cdot)right| boldsymbol{I}_{2}(boldsymbol{s})(boldsymbol{P} boldsymbol{t}) )
( mathbf{A} cdot_{E e l l}=E_{c e l l}^{circ}-frac{0.592}{n} log _{10}left[F e^{2+}right]left[I^{-}right]^{2} )
B. ( quad E_{text {cell }}=E_{text {cell }}^{circ}-frac{0.0592}{n} log _{10}left[mathrm{Fe}^{2+}right]left[I^{-}right]^{2} )
( ^{mathbf{C}} E_{text {cell }}=E_{text {cell }}^{circ}-frac{0.0592}{n} log _{10}left[F e^{2+}right]left[I^{-}right] )
D ( quad E_{text {cell }}=E_{text {cell }}^{circ}-frac{0.0592}{n} log _{10} frac{left[F e^{2+}right]left[I^{-}right]^{2}}{[F e]left[I_{2}right]} )
12
261 Q. 4 The difference between the electrode potentials of two electrodes when
no current is drawn through the cell is called.
(a) cell potential
(b) cell emf
(c) potential difference
(d) cell voltage
de botential of the lectrodes when no
12
262 The cell constant of a conductivity cell:
A. changes with change of electrolyte
B. changed with change of concentration of electrolyte
C. changes with temperature of electrolyte
D. remains constant for a cell
12
263 Specific conductance of a decinormal
solution of ( K C l ) is 0.0112 ohm ( ^{-1} c m^{-1} )
The resistance of a cell containing the
solution was found to be ( 56 . ) Waht is the
cell constant?
12
264 Conductivity of ( 0.00241 mathrm{M} ) acetic acid is ( mathbf{7} . mathbf{8} 9 mathbf{6} times mathbf{1 0}^{-5} mathbf{S} mathbf{c m}^{-1} . ) Calculate its
molar conductivity. If ( lambda_{m}^{o} ) for acetic acid is ( 390.5 S c m^{2} ) mol ( ^{-1} . ) what is its
degree of dissociation?
12
265 Q Type your question
Determine the time it would take to
plate ( 10.0 g A g ) with a current of ( 0.452 A )
A ( .2 .5 h r )
B. ( 3.5 h r )
c. ( 4.5 h r )
( 0.5 .5 h )
12
266 The first electro-chemical was invented
by:
A. Luigí Galvani
B. Alessandro Volta
c. Deniel.
D. Lechanche
12
267 The ions associated with salt bridge are
A. sodium
B. potassium
c. calsium
D. magnesium
12
268 A compound which liberates reddish brown gas around the anode during electrolysis in its molten state is
A. Sodium chloride
B. Copper (II) oxide
c. copper (II) sulphate
D. Lead (II) bromide
12
269 Question 14. Suggest two materials other than hydrogen that can be
used as fuels in fuel cells.
TOLD
12
270 Which of the following statements is/are incorrect?
This question has multiple correct options
A. Rust is ( F e_{2} O_{3} )
B. zn-Cu cell is called Daniell cell.
c. Saline water slows down rusting.
D. Pure metals undergo corrosion faster than impure metals.
12
271 we have taken a saturated solution of
AgBr. Ksp of AgBr is ( 12 times 10^{-4} ) if ( 10^{-7} )
mole of ( A g N O_{3} ) are added to 1 litre of
this solution then the conductivity of solution in terms of ( 10^{-7} S m^{-1} ) units
will be ( ? mathrm{GIVEN} boldsymbol{lambda} boldsymbol{A} boldsymbol{g}+=mathbf{4} times mathbf{1 0}^{-mathbf{3}} ; boldsymbol{lambda} )
( mathrm{Br}_{-}=6 times 10^{-3} mathrm{Sm}^{2} boldsymbol{m} )
12
272 According to Faraday’s first law, the amount of substance deposited at
electrode when an electric current is
passed through electrolyte depends
upon:
This question has multiple correct options
A. amount of current passed
B. dissociation of electrolyte
c. time till which current is passed
D. nature of electrode materia
12
273 For the given cell ( boldsymbol{P t}_{D_{2} mid D^{+}} | boldsymbol{H}^{+}|boldsymbol{P t}| boldsymbol{H}_{2} )
if ( boldsymbol{E}_{D_{2} mid D^{oplus}=0.003 V}^{ominus}, ) what will be the ratio of ( D^{oplus} ) and ( H^{oplus} ) at ( 25^{circ} C ) when he
reaction: ( D_{2}+2 H^{oplus} rightarrow 2 D^{oplus}+H_{2} )
attains equilibrium:
A .1 .34
B . 1.24
c. 1.124
D. 1.45
12
274 Which of the following solutions of Na ( C l ) will have the highest specific
conductance?
B. ( 0.1 N )
c. ( 0.01 N )
D. ( 1.0 N )
12
275 Assertion
The Daniell cell becomes dead after
sometimes.
Reason
The oxidation potential of Zn anode decreases and that of Cu increases.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
276 State True or False.
The mass of a substance deposited on
the cathode or anode during electrolysis is given by ( mathbf{w}=frac{boldsymbol{E} boldsymbol{i} boldsymbol{t}}{boldsymbol{F}} )
A. True
B. False
12
277 Given standard electrode potentials:
( boldsymbol{F} boldsymbol{e}^{boldsymbol{3}+}+boldsymbol{3} boldsymbol{e}^{-} longrightarrow boldsymbol{F} boldsymbol{e} ; boldsymbol{E}^{boldsymbol{o}}=-mathbf{0 . 0 3 6} boldsymbol{v o l} boldsymbol{t} )
( boldsymbol{F} boldsymbol{e}^{2+}+boldsymbol{2} boldsymbol{e}^{-} longrightarrow boldsymbol{F} boldsymbol{e} ; boldsymbol{E}^{o}=-mathbf{0 . 4 4 0} boldsymbol{v o l t} )
The standard electrode potential ( E^{o} ) for ( boldsymbol{F} boldsymbol{e}^{boldsymbol{3}+}+boldsymbol{e}^{-} longrightarrow boldsymbol{F} boldsymbol{e}^{boldsymbol{2}+} ) is:
A. 0.476 volt
B. 0.404 volt
c. 0.440 volt
D. 0.772 volt
12
278 ( boldsymbol{K}, boldsymbol{C} boldsymbol{a} ) and ( boldsymbol{L} boldsymbol{i} ) metals may be arranged
in the decreasing order of their standard electrode potentials
as
A. ( K, C a ) and ( L i )
в. ( L i, K ) and ( C a )
c. ( L i, ) Ca and ( K )
D. ( C a, L i ) and ( K )
12
279 Two students use same stock solution
of ( Z n S O_{4} ) and a solution of ( C u S O_{4} ). The
emf of one cell is ( 0.03 V ) higher than that of other. The concentration of
( C u S O_{4} ) in the cell with higher emf value
is ( 0.5 M . ) Find out the concentration of
( C u S O_{4} ) in the other cell. ( left(frac{2.303 R T}{F}=0.06right) )
12
280 Assertion
For the Daniel cell, ( Z nleft|Z n^{2+}right|left|C u^{2+}right| C u )
with ( E_{c e l l}=1.1 V, ) the application of
opposite potential greater than ( 1.1 mathrm{V} )
results into flow of electron from
cathode to anode.
Reason
( Z n ) is deposited at anode, and ( C u ) is
deposited at cathode.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
281 The electric batteries used in small
calculators are?
A. weston cell
B. Leclanche cell
c. Nickel-cadmium batteries
D. Lead acid batteries
12
282 Represent the cell in which the following
reaction takes place ( M g(s)+ )
( mathbf{2} boldsymbol{A} boldsymbol{g}^{+}(mathbf{0 . 0 0 0 1} boldsymbol{M}) rightarrow )
( M g^{2+}(0.130 M)+2 A g(s) )
Calculate its ( E_{(c e l l)} ) if ( E_{(c e l l)}^{o}=3.17 V )
12
283 The purpose of a salt bridge in a
galvanic cell is to:
A. prevent accumulation of charges around the electrodes
B. facilitate continuity of the cell reaction
c. to produce current at a constant strength
D. all of the above
12
284 The efficiency of an hypothetical cell is about ( 84 % ) which involves the following
reaction:
( boldsymbol{A}(s)+boldsymbol{B}^{2+}(boldsymbol{a} boldsymbol{q}) rightarrow boldsymbol{A}^{2+}(boldsymbol{a} boldsymbol{q})+ )
( B(s): Delta H=-285 k J )
Then, the standard electrode potential of the cell will be: (Assume as ( Delta S=0 ) )
A . 1.20
B. 2.40
c. ( 1.10 v )
D. 1.24
12
285 ( boldsymbol{C u}^{+}+boldsymbol{e}^{-} longrightarrow boldsymbol{C u}, quad boldsymbol{E}^{o}=boldsymbol{x}_{1} ) volt
( boldsymbol{C u}^{2+}+mathbf{2} e^{-} longrightarrow boldsymbol{C u}, quad boldsymbol{E}^{o}=boldsymbol{x}_{2} ) volt
then for
( boldsymbol{C u}^{+}+boldsymbol{e}^{-} longrightarrow boldsymbol{C u}^{+}, quad boldsymbol{E}^{o}(text { volt }) ) will be
A. ( x_{1}-2 x_{2} )
В. ( x_{1}+2 x_{2} )
c. ( x_{1}-x_{2} )
D. ( 2 x_{2}-x_{1} )
12
286 Molar conductance of a ( 0.2 mathrm{M} ) solution
of a weak acid, ( boldsymbol{H} boldsymbol{A} ) is ( 2.8 times 10^{-2} boldsymbol{S m}^{2} )
mol ( ^{-1} ). If the limiting molar conductance of ( boldsymbol{H} boldsymbol{A} ) is ( mathbf{5 6 0} mathbf{~} mathbf{S} boldsymbol{m}^{2} boldsymbol{m o l}^{-1} )
the dissociation constant of the acid is:
( mathbf{A} cdot 5 times 10^{-10} )
B . ( 10^{-10} )
C ( .5 times 10^{-5} )
D. ( 2 times 10^{-15} )
12
287 The units of conductivity are:
A. siemens ( ^{-1} mathrm{cm}^{-1} )
B. siemens cm
c. siemens ( c m^{-1} )
D. siemens ( c m^{-1} m o l^{-1} )
12
288 An iron wire is immersed in a solution
containing ( Z n S O_{4} ) and ( N i S O_{4} . ) Predict giving reasons which of the following reactions is likely to proceed?
(i) Iron reduces ( Z n^{2+} ) ions
(ii) Iron
reduces ( N i^{2+} ) ions.
Given: ( boldsymbol{E}_{boldsymbol{Z} n^{2+} / boldsymbol{Z} boldsymbol{n}}= )
-0.76 volt; ( E_{F e^{2+} / F e}^{circ}=-0.44 ) volt and
( boldsymbol{E}_{N i^{2+} / N i}^{circ}=-mathbf{0 . 2 5} ) volt.
12
289 When 9.65 coulomb of electricity is passed through a solution of silver nitrate, the amount of silver deposited is:
A. ( 16.2 mathrm{mg} )
B. ( 21.2 mathrm{mg} )
c. ( 10.8 mathrm{mg} )
D. ( 6.4 mathrm{mg} )
12
290 An excess of liquid Hg was added to
( 10^{-3} mathrm{M} ) acidified solution of ( F e^{3+} ) ions.
was found that only ( 4.6 % ) of the ions
remained as ( F e^{3+} ) at equilibrium at ( 25^{circ} )
C. Calculate ( boldsymbol{E}^{o} ) for ( mathbf{2} boldsymbol{H} boldsymbol{g} / boldsymbol{H} boldsymbol{g}_{2}^{2+} ) at ( boldsymbol{2} mathbf{5}^{boldsymbol{o}} mathbf{C} )
for,
( 2 H g+2 F e^{3+} rightleftharpoons H g_{2}^{2+}+2 F e^{2+} ) and
( boldsymbol{E}_{boldsymbol{F e}^{2+} / boldsymbol{F e}^{3+}}^{o}=-mathbf{0 . 7 7 1 2} boldsymbol{V} )
A. – -0.7912 V
в. – 0.7721 V
c. ( -0.9922 mathrm{v} )
D. None of these
12
291 Which is not true for a standard
hydrogen electrode?
A. It can act both as cathode and anode
B. Temperature is ( 273 mathrm{K} )
C. Pressure is 0 atm.
D. It contains a metallic conductor which does not
absorb hydrogen
12
292 Given below are the half-cell reactions:
( M n^{2+}+2 e^{-} rightarrow M n ; E^{o}=-1.18 V )
( mathbf{2}left(boldsymbol{M} boldsymbol{n}^{+mathbf{3}}+boldsymbol{e}^{-} rightarrow boldsymbol{M} boldsymbol{n}^{2+}right) ; boldsymbol{E}^{boldsymbol{o}}= )
( +1.51 V )
The ( boldsymbol{E}^{o} ) for ( boldsymbol{3} boldsymbol{M} boldsymbol{n}^{2+} rightarrow boldsymbol{M} boldsymbol{n}+boldsymbol{2} boldsymbol{M} boldsymbol{n}^{3+} )
will be:
A. ( +0.33 V ; ) the reaction will occur
B. ( -2.69 V ); the reaction will not occur
c. ( +2.69 V ; ) the reaction will occur
D. ( -0.33 V ); the reaction will not occur
12
293 Calculate the molar conductivity of water at infinite dilution (in ( mathrm{Sm}^{2} mathrm{mol}^{-1} ) ).
( molar conductivity of hydrogen ions and the molar conductivity of hydroxide ions at infinite dilution are ( 349.6 times 10^{-4} mathrm{Sm}^{2} )
( left.mathrm{mol}^{-1} text {and } 198.3 times 10^{-4} mathrm{Sm}^{2} mathrm{mol}^{-1}right) )
A . 547.9
B. 647.9
c. ( 647.9 times 10^{-4} )
D. ( 547.9 times 10^{-4} )
12
294 The following electrochemical cell has been set-up:
( boldsymbol{P t}(1) mid boldsymbol{F} e^{3+}, boldsymbol{F} boldsymbol{e}^{2+}(boldsymbol{a}= )
( mathbf{1})left|boldsymbol{C} boldsymbol{e}^{boldsymbol{4}+}, boldsymbol{C} boldsymbol{e}^{boldsymbol{3}+}(boldsymbol{a}=mathbf{1})right| boldsymbol{P} boldsymbol{t}(boldsymbol{2}) )
( E^{0}left(F e^{2+}, F e^{2+}right)=0.77 mathrm{V} )
and ( boldsymbol{E}^{0}left(boldsymbol{C} boldsymbol{e}^{boldsymbol{4}+}, boldsymbol{C} boldsymbol{e}^{boldsymbol{3}+}right)=1.61 mathrm{V} )
If an ammeter is connected between the
two platinum electrodes, predict the
direction of flow of current, will the
current increases or decreases with
time?
12
295 In ( _{-1}-ldots_{text {eactants are }} )
continuously supplied energy which can be withdrawn indefinately until outside supply of reactant is maintained. These
cells are more efficient than
conventional batteries and moreover,
these are eco-friendly.
A . fuel
B. galvanic
C. primary
D. secondary
12
296 In the electrolysis of aqueous sodium
chloride solution which of the half cell
reaction will occur at anode?
12
297 Spacecraft like the satellites that circle
the earth and are used in television
transmission have electric batteries
that supply power for various purposes These batteries contain ion-exchange resins instead of a liquid electrolyte
solution because:
A. of extreme cold conditions
B. of lack of oxygen
c. a high electric voltage is required
D. of zero gravity
12
298 What happens when a copper rod is
placed in ( F e S O_{4} ) solution?
12
299 During electroplating by electrolysis,
the article to be electroplated is:
A. Kept immersed in the electrolyte at the bottom.
B. Made the cathode of an electrolytic cell.
C. Made the anode of an electrolytic cell.
D. Made the electrolyte of the electrolytic cell.
12
300 We have taken a saturated solution of
( A g B r . K_{s p} ) of ( A g B r ) is ( 12 times 10^{-14} .1 f )
( 10^{-7} ) mole of ( A g N O_{3} ) are added to 1 litre of this solution find conductivity (specific conductance) of this solution in terms of ( 10^{-7} mathrm{Sm}^{-1} )
Given: ( lambda_{A g^{+}}^{0}=6 times 10^{-3} mathrm{Sm}^{2} mathrm{mol}^{-1} )
( lambda_{B r^{-}}^{0}=8 times 10^{-3} mathrm{Sm}^{2} mathrm{mol}^{-1} ) and
( lambda_{N O_{3}^{-}}^{0}=7 times 10^{-3} mathrm{Sm}^{2} mathrm{mol}^{-1}[ ) If answe
is ( X ) then give answer in form of ( frac{X}{11} )
12
301 By passing electric current, ( N a C l O_{3} ) is
converted into ( N a C l O_{4} ) according to
the following equation ( N a C l O_{3}+ )
( boldsymbol{H}_{2} boldsymbol{O} rightarrow boldsymbol{N} boldsymbol{a} boldsymbol{C l} boldsymbol{O}_{4}+boldsymbol{H}_{2} )
How many moles of ( N a C l O_{4} ) will be
formed when three Faradays of charge
is passed through ( N a C l O_{3} ? )
A . 1.5
в. 1.0
( c .3 .0 )
D. 0.75
12
302 The standard reduction potential of
( E_{B i^{3+} / B i}^{o} ) and ( E_{C u^{2+} / C u}^{o} ) are ( 0.226 mathrm{V} ) and
( 0.344 mathrm{V} ) respectively. A mixture of salts of Bi and Cu at unit concentration each
is electrolysed at ( 25^{circ} mathrm{C} ). To what value
( operatorname{can}left[C u^{2+}right] ) be brought down before
bismuth starts to deposit during electrolysis?
В. ( 10^{-3} M )
( mathbf{c} cdot 10^{-5} M )
D. ( 10^{-6} M )
12
303 The indication of the state of charge of a
battery is best given by:
A. specific gravity of electrolyte
B. temperature of electrolyte
c. colour of electrolyte.
D. level of electrolyte
12
304 The number of faradays of electricity required to decompose ( 100 mathrm{ml} ) water (density ( =0.99 mathrm{gm} / mathrm{ml} ) ) is:
A .2
B. 11
( c .100 )
D. 5.5
12
305 For the cell
( boldsymbol{P t}, boldsymbol{H}_{2}(boldsymbol{g}) mid boldsymbol{2} boldsymbol{M} boldsymbol{C} boldsymbol{H}_{3} boldsymbol{C O O N} boldsymbol{H}_{4} | mathbf{2} M boldsymbol{n} )
20
( operatorname{atm} quad 0.2 operatorname{atm} )
Given ( : boldsymbol{p} boldsymbol{K}_{boldsymbol{a}}left(boldsymbol{C H}_{3} boldsymbol{C O O H}right)=mathbf{4 . 7 4} ) and
( boldsymbol{p} boldsymbol{K}_{boldsymbol{b}}left(boldsymbol{N} boldsymbol{H}_{4} boldsymbol{O} boldsymbol{H}right)=mathbf{4 . 7 4} )
EMF of the cell in millivolt is: (Given
( left.frac{2.303 R T}{F}=0.059right) )
12
306 What is the amount of Al deposited on
the electrolysis of molten ( A l_{2} O_{3} ) when a current of ( 9.65 mathrm{A} ) is passed for ( 10.0 mathrm{s} )
12
307 In electrolyte concentration cell:
This question has multiple correct options
A. the electrode material and the solution in both halfcells are composed of the same substances
B. only the concentrations of solutions of the same substances is different
( mathbf{c} cdot E_{c e l l}^{circ}=0 )
D. the Nernst equation reduces to ( E_{text {cell}}= ) ( -left(frac{0.0591}{n}right) log Q ) at ( 25^{circ} mathrm{C} )
12
308 A conductance cell was filled with a
0.02 M KCl solution which has a specific conductance of ( 2.768 times )
( 10^{-3} ) oh ( m^{-1} c m^{-1} . ) If its resistance is
82.4 ohm at ( 25^{circ} mathrm{C}, ) then the cell constant
is:
A. ( 0.2182 mathrm{cm}^{-1} )
В. ( 0.2281 mathrm{cm}^{-1} )
c. ( 0.2821 mathrm{cm}^{-1} )
D. 0.2381 ( c m^{-1} )
12
309 Q. 15 While charging the lead storage battery ……..
(a) PbSO4 anode is reduced to Pb (b) Pbso, cathode is reaus
(c) PbSO4 cathode is oxidised to Pb (d) Pbso, anode is oxidise
ollie reversed and
bSO4 cathode is reduced to Pb
12
310 Which of the following gas is formed at the electrode connected to the negative
terminal of the battery?
A. Nitrogen gas
B. Hydrogengas
c. oxygen gas
D. carbon dioxide gas
12
311 Why metal gets deposited at the negative pole when electric current is passed through a metal salt??
A. Metal is negatively charged.
B. Metal is positively charged.
c. Metal does not have any charges.
D. Both a and c.
12
312 A current of 1.5 ampere is passed through a solution of a salt of a bivalent
metal for 30 minutes. Increase in mass
of cathode is ( 0.8898 g . ) Find the atomic
mass of the metal.
( A cdot 63 g )
B. 63.6 g
c. ( 73.6 g )
D. 70g
12
313 Indicate the correct statements.
This question has multiple correct options
A. Conductivity cells have cell constant values independent of the solution filled into the cell
B. DC (direct current) is not used for measuring the resistance of a solution
C. Kohlrausch law is valid both for strong and weak electrolytes
D. The k decreases but ( lambda_{M} ) and ( lambda_{E} ) increase on dilution
12
314 Q. 56 Assertion (A) Cu is less reactive than hydrogen.
Reason (R)
E is negative.
2+
I
OAN
12
315 If ( E_{C H_{3} C O O O H mid C_{2} H_{5} O H}^{ominus}=0.06 V, ) Then ( E_{c e l l}^{ominus} )
of the reaction taking place in alcohol meter is :
( mathbf{A} cdot 1.39 V )
B. ( 1.27 V )
c. ( 1.60 V )
D. ( 1.51 V )
12
316 In the galvanic cell :
( Z n / Z n^{2+}left(C_{1}right) | C u^{2+}left(C_{2}right) / C u )
( boldsymbol{E}_{c e l l}-boldsymbol{E}_{c e l l}^{o}=+mathbf{0 . 0 5 9 1} boldsymbol{V} . ) The value of
( frac{C_{1}}{C_{2}} ) at ( 298 K ) is:
A ( cdot 10^{-1} )
B. ( 10^{2} )
( c cdot 10^{-2} )
D. 10
12
317 Lead storage battery contains:
A. ( P b ) rod as anode
B. ( P b ) plates coated with ( P b O_{2} ) act as cathode
C . electrolyte is ( H_{2} S O_{4} )
D. all are currect
12
318 Hydrogen – Oxygen fuel cells are used in
space craft to supply:
A. power for heat and light
B. electrical power
c. oxygen
D. water
12
319 What is the correct formula for
determining the voltage of an electrochemical cell?
A ( cdot E_{text {cell }}^{0}=E_{text {cathode }}^{0}-E_{text {anode }}^{0} ) added
C ( cdot E_{text {constant }}^{0}=E_{text {cathode }}^{0}-E_{text {ande }}^{0} )
D. ( E_{text {constant}}^{0}=E_{text {cathode}}^{0}+E_{text {anode}}^{0} )
E . ( E_{c e l l}^{0}=-E_{text {cathode }}^{0}+E_{text {ande }}^{0} )
12
320 Assertion
Silver metal does not show any change
when it is placed in HCl solution.
Reason
Silver metal does not react with dilute
HCI
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
321 How many faradays of electricity will be
required by ( 3 times 10^{12} ) electrons?
12
322 An acid is a substance that produces
ions in a water solution
A. oxygen
B. nitrogen
c. carbon
D. hydrogen
12
323 The EMFs of the following cells are
( boldsymbol{C u}left|boldsymbol{C u}^{2+}(mathbf{1} boldsymbol{M}) | boldsymbol{A} boldsymbol{g}^{+}(mathbf{1} boldsymbol{M})right| boldsymbol{A} boldsymbol{g}, boldsymbol{E}^{o}= )
( 0.46 V )
( Z nleft|Z n^{2+}(1 M) | C u^{2+}(1 M)right| C u, E^{o}= )
( 1.10 V )
The EMF of the cell
( Z nleft|Z n^{2+}right|left|A g^{+}(1 M)right| A g ) will be:
A . ( 1.56 V )
B . ( -1.56 V )
c. ( 0.64 V )
D. ( 2.02 V )
12
324 can be obtained from
bauxite by
A. Aluminium, Electrolysis
B. Copper, Electroplating
c. Aluminium, Electroplating
D. Copper, Electrolysis
12
325 The standard reduction potential data
at ( 25^{circ} mathrm{C} ) is given below:
( mathbf{E}^{mathrm{o}}left(mathbf{F e}^{mathbf{3}+}, mathbf{F e}^{mathbf{2}+}right)=+mathbf{0 . 7 7} mathbf{V} )
( mathbf{E}^{mathbf{o}}left(mathbf{F e}^{mathbf{2}+}, mathbf{F e}right)=-mathbf{0 . 4 4} mathbf{V} )
( mathbf{E}^{mathrm{o}}left(mathbf{C u}^{2+}, mathbf{C u}right)=+mathbf{0 . 3 4} mathbf{V} )
( mathbf{E}^{circ}left(mathbf{C u}^{+}, mathbf{C u}right)=+mathbf{0 . 5 2 V} )
( mathbf{E}^{mathrm{o}}left[mathbf{O}_{2}(mathbf{g})+mathbf{4 H}^{+}+mathbf{4 e}^{-} rightarrow mathbf{2} mathbf{H}_{mathbf{2}} mathbf{0}right]= )
( +1.23 V )
( mathbf{E}^{circ}left[mathbf{O}_{2}(mathbf{g})+mathbf{2} mathbf{H}_{2} mathbf{O}+mathbf{4} mathbf{e}^{-} rightarrow mathbf{4 0} mathbf{H}^{-}right]= )
( +0.40 mathrm{V} )
( mathbf{E}^{circ}left(mathbf{C r}^{3+}, mathbf{C r}right)=-mathbf{0 . 7 4 V} )
( mathbf{E}^{mathbf{o}}left(mathbf{C r}^{2+}, mathbf{C r}right)=-mathbf{0 . 9 1} mathbf{V} )
Match ( mathrm{E}^{0} ) of the redox pair in List 1 with
the values given in List 2 and select the correct answer using the code given below the lists.
12
326 If ( E_{F e^{2+} / F e}^{0}=-0.441 mathrm{V} ) and ( E_{F e^{3+} / F e^{2+}}^{0}= )
( 0.771 mathrm{V}, ) the standard ( boldsymbol{E} boldsymbol{M} boldsymbol{F} ) of the
reaction,
( boldsymbol{F} boldsymbol{E}+mathbf{2} boldsymbol{F} boldsymbol{E}^{3+} rightarrow mathbf{3} boldsymbol{F} boldsymbol{E}^{2+} ) will be:
A ( .0 .330 V )
( V )
B. ( 1.653 V )
c. ( 1.212 V )
D. ( 0.111 V )
12
327 ionizes in a fused
or in aqueous solution state and furnish
positive ions other than ( boldsymbol{H}^{+} ) and
negative ions other than ( boldsymbol{O} boldsymbol{H}^{-} )
A. Mineral acids
B. Bases
c. lonic salts
D. compounds
12
328 The metal which cannot liberate ( H_{2} ) gas
from hydrochloric acid is:
( A cdot Z n )
B. cu
( mathrm{c} . ) мв
D. Al
12
329 What will be the emf for the given cell :
( P tleft|H_{2}left(P_{1}right)right| H^{+}(a q)left|H_{2}left(P_{2}right)right| P t )
( ^{text {A } cdot} frac{R T}{F} log frac{P_{1}}{P_{2}} )
в. ( frac{R T}{2 F} log frac{P_{1}}{P_{2}} )
c. ( frac{R T}{F} log frac{P_{2}}{P_{1}} )
D. noneofthese
12
330 ( C u(S)+2 A g^{+}(a q) rightarrow C u^{2+}(a q)+2 A g(S) )
In the given reaction, the reduction half
cell reaction is:
A ( cdot mathrm{Cu}^{2+}+2 mathrm{e}^{-} rightarrow mathrm{cu} )
B. ( operatorname{cu} 2 e^{-} rightarrow c u^{2} )
( mathrm{c} cdot mathrm{Ag}^{+}+mathrm{e}^{-} rightarrow mathrm{Ag} )
D. ( A g e^{-} rightarrow A g^{+} )
12
331 Identify the reaction taking place at
cathode in fuel cell.
A. ( O_{2}+2 H_{2} O+4 e^{-} rightarrow 4 O H^{-} )
B ( cdot 2 H_{2}+4 O H^{-} rightarrow 4 H_{2} O+4 e^{-} )
c. ( O_{2}+2 H_{2} O+4 e^{-} rightarrow 4 O H^{-}+H^{+} )
D. ( 4 H_{2} O+4 e^{-} rightarrow 2 H^{2}+4 O H^{-} )
12
332 ( ln H_{2}-O_{2} ) fuel cell a reaction occuring
at cathode is:
A. ( 2 H_{2} O+O_{2}+4 e^{-} rightarrow 4 O H^{-} )
В. ( 2 H_{2}+O_{2} rightarrow 2 H_{2} O(l) )
( mathrm{c} cdot H^{+}+O H^{-} rightarrow H_{2} mathrm{O} )
D. ( H^{+}+e^{-} rightarrow frac{1}{2} H_{2} )
12
333 The storage battery generally used in electric power station is:
A. Nickel-Cadmium battery
B. zinc-Carbon battery
c. Lead-Acid battery
D. None of the above
12
334 At equimolar concentrations of ( boldsymbol{F} boldsymbol{e}^{2+} )
and ( F e^{3+}, ) what must ( left[A g^{+}right] ) be so that
the voltage of the galvanic cell made
from the ( left(A g^{+} mid A gright) ) and ( left(F e^{3+} mid F e^{2+}right) ) electrodes equals zero? ( boldsymbol{F} boldsymbol{e}^{2+}+boldsymbol{A} boldsymbol{g}^{+} rightleftharpoons boldsymbol{F} boldsymbol{e}^{boldsymbol{3}+}+boldsymbol{A} boldsymbol{g} )
( boldsymbol{E}_{A boldsymbol{g}^{o} mid boldsymbol{A} boldsymbol{g}}^{o}=boldsymbol{0 . 7 9 9 1} ; boldsymbol{E}_{boldsymbol{F e}^{3+} mid boldsymbol{F} e^{2-}}=mathbf{0 . 7 7 1} )
A .0 .34
B. 0.44
c. 0.47
D. 0.61
12
335 Q. 32 Aqueous copper sulphate solution and aqueous silve
are electrolysed by 1 ampere current for 10 minu
electrolytic cells. Will the mass of copper and silver depo.
cathode be same or different? Explain your answer.
thoda According to Faraday’s
on and aqueous silver nitrate solution
current for 10 minutes in separate
of copper and silver deposited on the
A
nrding
Dufor
12
336 A photo-cell employs photoelectric
effect to convert:
A. change in the frequency of light into a change in electric voltage.
B. change in the intensity of illumination into a change in photoelectric current.
C. change in the intensity of illumination into a change in the work function of the photocathode.
D. change in the frequency of light into a change in the electric current.
12
337 ( operatorname{acts} ) as the anode.
( mathbf{A} cdot Z n(s) )
B. ( C u^{2+}(a q) )
( mathbf{c} cdot Z n^{2+}(a q) )
( mathbf{D} cdot C u(s) )
E ( . H_{2} O )
12
338 The standard electrode potential ( boldsymbol{E}_{l_{2} / r}^{o}, quad boldsymbol{E}_{B r^{-} / B r_{2}}^{0} quad ) and ( quad boldsymbol{E}_{boldsymbol{F} e / F e^{2+}}^{0} ) are
respectively ( +0.54 mathrm{V},-1.09 mathrm{V} ) and ( 0.44 mathrm{V} . ) On
the basis of above data which of the
following process is non spontaneous?
( mathbf{A} cdot B r_{2}+2 I^{1} rightarrow 2 B r+I_{2} )
B. ( F e+B r_{2} longrightarrow F e^{2+}+2 B r )
C. ( F e+I_{2} longrightarrow F e^{2+}+2 I^{-} )
D. ( I_{2}+B r longrightarrow 2 I^{-}+B r_{2} )
12
339 The resistance of ( 0.01 mathrm{N} ) solution of an
electrolyte ( A B ) at ( 328 mathrm{K} ) is 100 ohm. The specific conductance of solution is :
( left[text { cell constant }=1 mathrm{cm}^{-1}right] )
A. 100 ohm
B. ( 10^{-2} ) ohm ( ^{-1} )
( mathbf{c} cdot 10^{-2} operatorname{ohm}^{-1} c m^{-1} )
D. ( 10^{2} ) ohm ( -c m )
12
340 The charge required to reduce 1 mole
( mathrm{Cr}_{2} mathrm{O}_{7}^{2-} ) to ( mathrm{Cr}^{3+} ) ions is:
( mathbf{A} cdot 3 F )
B. ( 3 C )
( mathbf{c} cdot 6 F )
D . ( 2 times 6.023 times 10^{23} e^{-} )
12
341 Corrosion can not be prevented by which of the following method?
A. Use of an anode connected to a direct current power
B. Create a barrier between the object being corroded and oxygen
c. Painting
D. Exposing it to sunlight
12
342 The e.m.f. of the cell
( boldsymbol{A} boldsymbol{g}|boldsymbol{A} boldsymbol{g} boldsymbol{C l} | boldsymbol{K} boldsymbol{C l}(boldsymbol{a q} .)| boldsymbol{H}_{2} boldsymbol{C l}_{2} mid boldsymbol{H} boldsymbol{g} ) is
( 0.0455 mathrm{K} ) at ( 298 mathrm{K} ) and the temperature
coefficient is ( 3.38 times 10^{-4} V K^{-1} . ) The
reaction is taking place is:
A. ( H g_{2} C l_{2}(s)+2 A g(s) rightarrow 2 A g C l(s)+2 H g(l) )
B. ( H g_{2} C l_{2}(s)+3 A g(s) rightarrow 3 A g C l(s)+4 H g(l) )
C. ( H g_{2} C l_{2}(s)+A g(s) rightarrow 2 A g C l(s)+4 H g(l) )
D. none of these
12
343 The value of cell constant ( left(text { in } m^{-1} ) ) is: right.
write your answer to nearest integer)
12
344 The equilibrium constant of the reaction
( boldsymbol{C}_{boldsymbol{u}}(boldsymbol{s})+boldsymbol{2} boldsymbol{A} boldsymbol{g}^{+}(boldsymbol{a} boldsymbol{q}) rightarrow boldsymbol{C} boldsymbol{u}^{2+}(boldsymbol{a} boldsymbol{q})+ )
( mathbf{2} boldsymbol{A} boldsymbol{g}(boldsymbol{s}) ; boldsymbol{E}^{0}=mathbf{0 . 4 6} boldsymbol{V} boldsymbol{a} boldsymbol{t} mathbf{2} boldsymbol{9} boldsymbol{8} boldsymbol{K} ) is:
( mathbf{A} cdot 4.0 times 10^{15} )
B . ( 2.4 times 10^{10} )
c. ( 2.0 times 10^{10} )
D. ( 4.0 times 10^{10} )
12
345 Three faradays of electricity are passed
through molten ( A l_{2} O_{3}, ) aqueous
solution of ( C u S O_{4} ) and molten ( N a C l )
taken in three different electrolytic cells. The amount of ( A l, C u ) and ( N a ) deposited at the cathodes will be in the
ratio of
A. 1 mole : 1 mole : 1 mole
B. 1 mole : 1.5 mole: 3 mole
c. 3 mole : 2 mole : 1 mole
D. 1 mole : 1.5 mole: 2 mole
12
346 The standard emf for the cell reaction,
( Z n+C u^{2+} rightarrow Z n^{2+}+C u )
is 1.10 volt at ( 25^{circ} mathrm{C} ). The emf for the cell
reaction when ( 0.1 M C u^{2+} ) and
( 0.1 M Z n^{2+} ) solutions are used at ( 25^{circ} mathrm{C} )
is:
A. 1.10 volt
B. 0.110 volt
c. -1.10 volt
D. -0.110 volt
12
347 What is the density of solution of sulphuric acid used as an electrolyte in lead accumulator?
( mathbf{A} cdot 1.5 mathrm{gm} L^{-1} )
B. ( 1.2 mathrm{gm} L^{-1} )
c. ( 1.8 mathrm{gm} L^{-1} )
D. ( 2.0 mathrm{gm} L^{-1} )
12
348 A weak electrolyte having the limiting equivalent conductance of ( 400 S mathrm{cm}^{2} g )
equiv ( ^{-1} ) at ( 298 K ) is ( 2 % ) ionized in its ( 0.1 N ) solution. The resistance of this
solution (in ohm) in an electrolytic cell of cell constant ( 0.4 mathrm{cm}^{-1} ) at this
temperature is:
A . 200
в. 300
c. 400
D. 500
E. 600
12
349 Which of the following gas is formed at the electrode, connected to the positive terminal of the battery?
A. Nitrogen gas
B. Hydrogengas
c. oxygen gas
D. carbon dioxide gas
12
350 During discharging of a lead storage
battery, which of the following is/are
true?
This question has multiple correct options
( mathbf{A} cdot H_{2} S O_{4} ) is produced
B. ( H_{2} O ) is consumed
( mathrm{C} cdot P b S O_{4} ) is formed at both electrodes
D. Density of electrolytic solution decreases
12
351 Consider the following concentration cell
( Z n(s)left|Z n^{2+}(0.024 M) | Z n^{2+}(0.480 M)right| Z )
which of the following statements
is/are correct?

This question has multiple correct options
A. The EMF of the cell at ( 25^{circ} mathrm{C} ) is nearly ( +0.039 mathrm{V} )
B. The EMF of the cell at ( 25^{circ} C ) is nearly -0.039 V.
C. If water is added in LHE, so that the ( left[Z n^{2+}right] ) is reduced to ( 0.012 mathrm{M} ), the cell voltage increases.
D. If water is added in LHE, so that the ( left[Z n^{2+}right] ) is reduced to ( 0.012 mathrm{M} ), the cell voltage decreases.

12
352 The volume of gases evolved at ( S T P ) by
passing ( 0.1 A ) of current for ( 965 g ) through an aqueous solution of
potassium acetate:
A . ( 22.4 m L )
в. ( 11.2 m L )
( c .89 .6 m L )
D. ( 44.8 mathrm{mL} )
12
353 The standard e.m.f. of the cell involving
the reaction, ( 2 A g^{+}(a q)+H_{2}(g) rightarrow )
( 2 A g(s)+2 H^{+}(a q), ) is ( 0.80 mathrm{V} . ) The
standard oxidation potential of ( mathrm{Ag} ) electrode is:
A . ( 0.80 V )
в. ( -0.80 V )
c. ( 0.40 V )
D. ( 0.20 V )
12
354 If ( E^{o} ) denotes reduction potential, then
which is true?
( mathbf{A} cdot E_{c e l l}^{0}=E_{r i g h t}^{o}-E_{l e f t}^{o} )
B ( cdot E_{text {cell }}^{0}=E_{text {left }}^{o}+E_{text {right }}^{o} )
( mathbf{c} cdot E_{c e l l}^{0}=E_{l e f t}^{o}-E_{r i g h t}^{o} )
D. ( E_{c e l l}^{0}=-left(E_{l e f t}^{o}+E_{r i g h t}^{o}right) )
12
355 One ampere hour charge is equivalent
to :
A. 36 coulombs
B. 360 coulombs
c. 3600 coulombs
D. 36000 coulombs
12
356 When the free ends of a tester are
dipped into a solution, the magnetic needle shows deflection due to:
A . electrical effect
B. mechanical effect
c. magnetic effect
D. lighting effect
12
357 A shiny brown-coloured element ‘X’ on heating in air becomes black in colour
Name the element ‘X’?
A. Sodium
B. Calcium
c. copper
D. Aluminium
12
358 Why distilled water does not conduct
electricity?
12
359 What is the potential of the cell containing two hydrogen electrodes as represented below?
( boldsymbol{p t} ; frac{1}{2} boldsymbol{H}_{2}(boldsymbol{g})left|boldsymbol{H}_{2} boldsymbol{O}right|left|boldsymbol{H}^{oplus}(mathbf{0 . 0 0 1} boldsymbol{M})right| mathbf{1} / mathbf{2} boldsymbol{H} )
A. ( -0.236 V )
В. ( -0.0591 V )
c. ( 0.236 V )
D. ( 0.0591 V )
12
360 A) Electrolysis of NaCl solution gives chlorine at anode
Q. 61 Assertion (A) Electrolysis of NaCl solution
instead of 02.
Reason (R) Formation of oxygen at anode requires over voltage.
Jonation of
12
361 Electrolysis of water is carried out in hoffman voltameter. Litmus is added to
both cathodic and anodic
compartments.What changes do you observe in the above process at the end of electrolysis? Justify.
12
362 Aluminum displaces hydrogen in dil. HCl whereas silver does not. The e.m.f of
a cell prepared by combination ( A l / A l^{3+} ) and ( A g / A g^{+} ) is 2.46 V. The
reduction potential reduction potential of aluminum electrodes is:
A ( .+1.66 v )
B. – -3.26 V
( c .+3.26 v )
D. -1.66 V
12
363 A current of 9.95 amperes flowing for 10 minutes, deposits ( 3 g ) of metal. An equivalent weight of the metal is:
A . 12.5
B. 18.5
c. 21.5
D. 48.5
12
364 The quantity of charge (in Faraday)
required to electrolyse ( 54 mathrm{g} mathrm{H}_{2} mathrm{O} ) is :
12
365 0.46 Write the Nernst equation for the cell reaction in the Daniel cell. How
will the Ecell be affected when concentration of Zn2+ ions is increased?
12
366 In a copper wire, current is the flow of :
A. positive charge
B. negative charge
c. both a and b
D. none of above
12
367 The solubility product of a saturated
solution of ( A g_{2} C r O_{4} ) in water at ( 298 mathrm{K} ) will
be……………., if the EMF of the cell:
( boldsymbol{A} boldsymbol{g} mid boldsymbol{A} boldsymbol{g}^{oplus}left(boldsymbol{s} boldsymbol{a} boldsymbol{t} boldsymbol{A} boldsymbol{g}_{2} boldsymbol{C r} boldsymbol{O}_{4} boldsymbol{s o l}right) | boldsymbol{A} boldsymbol{g}(boldsymbol{0} . boldsymbol{1} boldsymbol{M} )
is ( 0.164 V ) at ( 298 mathrm{K} )
A. ( 2.287 times 10^{-12} M^{3} )
B . ( 2.659 times 10^{-12} M^{3} )
c. ( 1.965 times 10^{-12} M^{3} )
D. None of these
12
368 The conductivity at infinite dilution of
( N H_{4} C l, N a O H ) and ( N a C l ) are
( 130,218,120 o h m^{-1} c m^{2} e q^{-1} . ) If
equivalent conductance of ( frac{N}{100} ) solution
of ( N H_{4} O H ) IS ( 10, ) then degree of
dissociation of ( N H_{4} O H ) at this
dilution is:
A. 0.005
B. 0.043
c. 0.015
D. 0.025
12
369 Corrosion is the process of rusting of any kind of metal or alloy due to the presence of moisture and air in it’s
surrounding. As it comes in contact with air and water it reacts with it and a
layer is formed above it’s surface. Type 1
for true and 0 for False.
12
370 Match the following. 12
371 Which of the following is a chemical effect of electric current?
A. Formation of gas bubbles on the electrodes
B. Change of color of solution
c. Deposition of metals on the electrodes
D. All of the above
12
372 Question 24. What is the relationship between Gibbs free
cell reaction in a galvanic cell and the emf of the cell? When will the
maximum work be obtained from a galvanic cell?
12
373 The emf of the cells obtained by combining zinc and copper electrodes of the Daniell cell with calomel
electrodes are 1.083 volt and
-0.018 volt respectively at ( 25^{circ} mathrm{C} . ) If the
reduction potential of normal calome electrode is +0.28 volt, find he emf of the Daniell cell.
12
374 The standard e.m.f. of a cell involving one electron change is found to ( 0.591 mathrm{V} )
at ( 25^{circ} mathrm{C} ). The equilibrium constant of the
reaction is:
A ( cdot 10^{30} )
B . ( 10^{5} )
( c cdot 10^{10} )
D. ( 10^{text { }} )
12
375 Amount of zinc deposited when ( 3.01 times )
( 10^{20} ) electrons pass through ( Z n S O_{4} )
solution is:
A . ( 16.35 g )
B . ( 16.375 times 10^{-3} g )
c. ( 32.7 times 10^{-3} g )
D. 32.7g
12
376 During electrolysis of fused calcium hydride, the hydrogen is produced at:
A. cathode
B. anode
c. hydrogen is not liberated at all
D. ( H_{2} ) produced reacts with oxygen to form water
12
377 Which one of the following scientists showed that if electrodes are immersed
in water and a current was passed, bubbles of oxygen and hydrogen were produced?
A. William Thomson
B. William Nicholson
c. william watson
D. William Harvey
12
378 A conductivity cell filled with ( 0.01 M )
KCl gives at ( 25^{circ} mathrm{C} ) the resistance of
604 ohms. The conductivity of ( K C l ) at
( 25^{circ} C ) is ( 0.00141 Omega^{-1} c m^{-1} . ) The same
cell filled with ( 0.001 M A g N O_{3} ) gives a
resistance of 6529 ohms. Calculate the
molar conductivity of ( 0.001 M A g N O_{3} )
solution at ( 25^{circ} mathrm{C} )
12
379 0.53 Match the items of Column I and Column II.
Column 1 Column II
Α. κ
1. Ixt
В.
2. Amlan
ca 3.
D.
O
12
380 The
( boldsymbol{E}^{ominus} ) for ( boldsymbol{C u}^{2+} / boldsymbol{C u}^{oplus}, boldsymbol{C u}^{oplus} / boldsymbol{C u}, boldsymbol{C u}^{2+} / boldsymbol{C} )
are ( 0.15 vee, 0.50 mathrm{V}, ) and ( 0.325 mathrm{V} )
respectively. The redox cell showing redox reaction ( 2 C u^{+}, rightarrow C u^{2+}+C u )
is made. ( E^{ominus} ) of this cell reaction and
( Delta G^{ominus} ) may be :
A ( cdot E^{ominus}=0.175 V ) or ( E^{ominus}=0.350 V )
B. ( n=1 ) or 2
c. ( Delta G^{ominus}=-33.775 k J )
D. All of these
12
381 State True or False.
The effect of a change in the concentration of a reactant or product on the cell voltage can be predicted by applying Le-chateliers principle.
A. True
B. False
12
382 Entropy change in ( mathrm{JK}^{-1} )
is
(Give answer to the nearest integer)
12
383 Calculate ( boldsymbol{K}_{c} ) for ( boldsymbol{H} boldsymbol{g}^{2+}+boldsymbol{H} boldsymbol{g} rightleftharpoons boldsymbol{H} boldsymbol{g}_{2}^{2+} )
Give that ( E_{2 H g / H g^{2+}}^{o}=-0.788 V ) and
( boldsymbol{E}_{boldsymbol{H} boldsymbol{g}_{2}^{2+} / mathbf{2 H g}^{2+}}^{boldsymbol{o}}=-mathbf{0 . 9 2 0} boldsymbol{V} )
Write answer as nearest integer after dividing by 100
12
384 is defined as a process
where materials, usually metals, deteriorate as a result of a chemical
reaction with air, moisture, chemical
etc. For example, iron, in the presence of
moisture, reacts with oxygen to form hydrated iron oxide.
12
385 Assertion
( H_{2} S ) reacts with oxygen under standard
conditions in acid medium to give ( boldsymbol{H}_{2} boldsymbol{O} )
and sulphur.
Reason
( boldsymbol{E}_{boldsymbol{H}^{+} / boldsymbol{O}_{2} / boldsymbol{P t}}>boldsymbol{E}_{boldsymbol{H}^{+} / boldsymbol{H}_{2} boldsymbol{S} / boldsymbol{S}}^{boldsymbol{o}} )
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
386 Glucose solution is an electrolyte and hence conducts electricity.
A. True
B. False
12
387 Conductivity of ( C a C l_{2} ) solution is:
A ( cdot 4.87 times 10^{-4} mathrm{Scm}^{1} )
B. ( 7.84 times 10^{-4} mathrm{Scm}^{1} )
c. ( 8.47 times 10^{-4} mathrm{Scm}^{1} )
D. None of these
12
388 Calculate the amount of charge required to deposit 1.0 g of sodium metal(molar mass 23.0 g ( m o l^{-1} ) ) from sodium ion.
A . 2098
B. 96500
c. 193000
D. 4196
12
389 Two half-cells have potentials -0.44 and 0.799 volt respectively. These two are coupled to make a galvanic cell. Which of the following will be true?
A. Electrode of half-cell potential ( -0.44 mathrm{V} ) V will act as anode
B. Electrode of half-cell potential -0.44 V will act as cathode
c. Electrode of half-cell potential ( 0.799 mathrm{V} ) will act as anode
D. Electrode of half-cell potential ( -0.44 mathrm{V} ) will act as a positive terminal
12
390 A Science teacher wrote 3 statements
about rancidity:
(i) When fats and oils are reduced, they become rancid
(ii) In chips packet, rancidity is
prevented by oxygen
(iii) Rancidity is prevented by adding antioxidants.
Selects the correct option.
A. (i)
B. (ii) and (iii)
c. (iii)
D. (i), (ii) and (iii)
12
391 An example of secondary battery cell is:
A. Edison Alkaline cell
B. Daniel cell.
c. Lachanche cell.
D. Bunsen cell.
12
392 The molar conductivities of ( wedge_{N a O A C}^{0} ) and ( wedge_{H C l}^{0} ) at infinite dilution in water at ( 25^{0} C ) and 91.0 and ( 426.2 mathrm{Scm}^{2} / mathrm{mol} ) respectively. To calculate ( wedge_{H O A c}^{0} ), the additional value required is:
( mathbf{A} cdot wedge_{N a C l}^{0} )
B. ( wedge_{H_{2} O}^{0} )
c. ( wedge_{K C l}^{0} )
D. ( wedge_{N a O H}^{0} )
12
393 The molar conductance at infinite
dilution of ( A g N O_{3}, A g C l ) and ( N a C l )
are 116.5,121.6 and 110.3 respectively.
The molar conductance of ( N a N O_{3} ) is:
( mathbf{A} cdot 111.4 )
B. 105.2
c. 130.6
D. 150.2
12
394 ( ln ) a ( H_{2}-O_{2} ) fuel cell, combustion of
hydrogen occurs to:
A. remove adsorbed oxygen from electrode surface
B. create potential difference between the two electrodes
c. produce high purity water
D. generate heat
12
395 For the cell (at ( 298 mathrm{K} ) ), which of the
following is correct?
( boldsymbol{A} boldsymbol{g}(boldsymbol{s})|boldsymbol{A} boldsymbol{g} boldsymbol{C l}(boldsymbol{s})| boldsymbol{C l}^{-}(boldsymbol{a} boldsymbol{q}) | boldsymbol{A} boldsymbol{g} boldsymbol{N} boldsymbol{O}_{3}(boldsymbol{a} boldsymbol{q}) mid boldsymbol{A} )
A. The cell emf will be zero when ( ( left.left[mathrm{Ag}^{+}right]right) ) in anodic compartment ( =left[mathrm{Ag}^{+}right] ) in cathodic compartment
B. The amount of AgCl(s) precipitate in anodic compartment will decrease will the working of the cell
C. The concentration of ( left[mathrm{Ag}^{+}right]= ) constant, in anodic compartment during working of cell
D. ( E_{text {cell}}=E_{A g^{+} mid A g}^{0}-E_{C l^{-}|A g C l| A g}^{0}-frac{0.059}{1} log frac{1}{left[C l^{-}right]_{a}} )
12
396 The potential of hydrogen electrode at
( 25^{circ} C ) will be:
( left(P_{H_{2}}=1 text { atm, concentration of } boldsymbol{H}^{+}=right. )
( mathbf{0 . 1} boldsymbol{M} )
( mathbf{A} cdot 0.00 V )
В. ( -0.059 V )
c. ( 0.118 V )
D. ( 0.059 V )
12
397 When an aqueous solution of ( boldsymbol{A} boldsymbol{g} boldsymbol{N} boldsymbol{O}_{3} ) is
electrolysed between platinum electrodes, the substances liberated at anode and cathode are:
A. silver is deposited at cathode and ( O_{2} ) is liberated at
anode
B. Silver is deposited at cathode and ( H_{2} ) is liberated at anode
C. Hydrogen is liberated at cathode and ( O_{2} ) is liberated at anode
D. Silver is deposited at cathode and Pt is dissolved in electrolyte
12
398 ( boldsymbol{Z} boldsymbol{n}left|begin{array}{c}boldsymbol{Z} boldsymbol{n}left(boldsymbol{N} boldsymbol{O}_{3}right)_{2}(boldsymbol{a} boldsymbol{q}) \ boldsymbol{1} mathbf{0} boldsymbol{0} boldsymbol{m} boldsymbol{L}, boldsymbol{1} boldsymbol{M}end{array}right|left|begin{array}{c}boldsymbol{C u}left(boldsymbol{N} boldsymbol{O}_{3}right)_{2}(boldsymbol{a} boldsymbol{q}) \ boldsymbol{1} mathbf{0} boldsymbol{0} boldsymbol{m} boldsymbol{L}, mathbf{1} boldsymbol{M}end{array}right| )
The following galvanic cell was operated as an electrolytic cell using Cu as anode
and ( mathrm{Zn} ) as cathode. A current of 0.48
ampere was passed for 10 hour and then the cell was allowed to function as
galvanic cell. The e.m.f. of the cell at ( 25^{circ} )
( mathrm{C} ) is (write the nearest integer value):
Assume that the only electrode reactions occurring were those
involving ( boldsymbol{C} boldsymbol{u} / boldsymbol{c u}^{2+} ) and ( boldsymbol{Z} boldsymbol{n} / boldsymbol{Z} boldsymbol{n}^{2+} )
Given
( E_{C u^{2+}, C u}^{o}=0.34 V ) and ( E_{Z n, Z n^{2+}}^{o}= )
( -0.76 V )
12
399 ( boldsymbol{A} boldsymbol{g} mid boldsymbol{A} boldsymbol{g}^{oplus}(boldsymbol{1} boldsymbol{M})left|boldsymbol{A} boldsymbol{g}^{oplus}right| boldsymbol{A} boldsymbol{g} )
( 0.5 mathrm{F} ) electricity is first passed in this LHS (anode) and 1 F of electricity is passed in the RHS (cathode) making them independent electrolytic cells at 298 K. EMF of the cell after electrolysis
will:
A. increase
B. decrease
c. not change
D. none of the above
12
400 Balanced equation of the reaction of
formation of ( P b O_{2} ) at the anode is
( P b^{2+}(a q)+x H_{2} O rightleftharpoons P b O_{2} downarrow )
( +boldsymbol{y} boldsymbol{H}^{+}(boldsymbol{a} boldsymbol{q})+boldsymbol{z} boldsymbol{e}^{-} )
What will be value of y?
12
401 Assertion
If ( boldsymbol{lambda}_{N a^{+}}^{circ} ) and ( boldsymbol{lambda}_{C l^{-}}^{circ} ) are molar limiting
conductivity of sodium and chloride ions respectively, then the limiting
molar conductivity for sodium chloride
is given by the equation: ( wedge_{N a C l}^{circ}= ) ( boldsymbol{lambda}_{N a^{+}}^{circ}+boldsymbol{lambda}_{C l^{-}}^{circ} )
Reason
This is according to Kohlrausch law of independent migration of ions.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
402 Given the following molar conductivity
at infinite dilution and ( 25^{circ} mathrm{C} )
( mathrm{HCl}: wedge_{m}^{infty}=426.2 mathrm{S} mathrm{cm}^{2} mathrm{mol}^{-1} mathrm{KCl}: wedge_{m}^{infty}= )
( 114.42 mathrm{S} mathrm{cm}^{2} mathrm{mol}^{-1} mathrm{CH}_{3} mathrm{COOK}: wedge_{m}^{infty}= )
( 149.86 mathrm{s} mathrm{cm}^{2} mathrm{mol}^{-1} )
The molar conductance at infinite
dilution and ( 25^{circ} mathrm{C}, ) for acetic acid
solution is:
A. ( 390.76 mathrm{Scm}^{2} mathrm{mol}^{-1} )
B . ( 461.86 mathrm{Scm}^{2} mathrm{mol}^{-1} )
c. ( 289.63 mathrm{Scm}^{2} mathrm{mol}^{-1} )
D. ( 172.94 mathrm{Scm}^{2} mathrm{mol}^{-1} )
12
403 Electrolysis involves conversion of
chemical energy to electrical energy.
A. True
B. False
12
404 Consider the table of standard
reduction potentials shown below.
Half-reaction
[
begin{array}{ll}
C l_{2}+2 e^{-} rightarrow 2 C l^{-} & 1.36 V \
O_{2}+4 H^{+}+4 e^{-} rightarrow 2 H_{2} O & 1.23 V \
2 H_{2} O+2 e^{-} rightarrow H_{2}+2 O H^{-} & -0.83 V \
R b^{+}+e^{-} rightarrow R b & -2.93 V
end{array}
]
Use the information from the table and
your knowledge of electrochemistry to
predict the CORRECT net ionic equation
for the reaction that will occur when an
aqueous solution of rubidium chloride
undergoes electrolysis.
( mathbf{A} cdot 2 R b^{+}+2 C l^{-} rightarrow 2 R b+C l_{2} )
B ( cdot 2 H_{2} O rightarrow 2 H_{2}+O_{2} )
( mathbf{c} cdot H_{2}+2 O H^{-}+2 R b^{+} rightarrow 2 R b+2 H_{2} O )
( mathbf{D} cdot 4 C l^{-}+O_{2}+4 H^{+} rightarrow 2 H_{2} O+2 C l_{2} )
12
405 Calculate the electrode potential at a copper electrode dipped in a ( 0.1 M )
solution of copper sulphate at ( 25^{circ} mathrm{C} ). The standard electrode potential of ( C u^{2+} / C u ) system is 0.34 volt at ( 298 K )
12
406 Chromium plating can involve the
electrolysis of an electrolyte of an
acidified mixture of chromic acid and
chromium sulphate. If during electrolysis the article being plated
increases in mass by ( 2.6 mathrm{g} ) and ( 0.6 mathrm{dm}^{3} ) of oxygen are evolved at an inert anode,
the oxidation state of chromiumions
being discharged must be : (assuming atomic weight of ( mathrm{Cr}=52 ) and 1 mole of
gas at room temperature and pressure
occupies a volume of ( left.24 d m^{3}right) )
A . -1
в. Zero
( c cdot+1 )
D. +2
12
407 Which of the following oxide(s) of iron would be obtained on prolonged reaction of iron with steam?
A. FeO
в. ( F e_{2} O_{3} )
( mathbf{c} cdot F e_{3} O_{4} )
D. ( F e_{2} O_{3} ) and ( F e_{3} O_{4} )
12
408 Copper sulphate solution ( (250 mathrm{ml}) ) was electrolysed using a platinum anode and a copper cathode. A constant current of ( 2 mathrm{mA} ) was passed for 16 minutes. It was found that after
electrolysis, the absorbance of the solution was reduced to ( 50 % ) of its
original value. Calculate the concentration of copper sulphate in the solution to begin with.
A ( .0 .22 M )
в. 2 М
c. ( 0.04 M )
D. ( 0.13 M )
12
409 The standard ( E_{r e d}^{o} ) values of ( A, B ) and ( C ) ( operatorname{are}+mathbf{0 . 6 8} boldsymbol{V},-mathbf{2 . 5 4} boldsymbol{V},-mathbf{0 . 5 0} boldsymbol{V} )
respectively. The order of their reducing power is:
A. ( A>B>C )
в. ( A>C>B )
c. ( C>B>A )
D. ( B>C>A )
12
410 If a current of 1.5 ampere flows through a metallic wire for 3 hours, then how many electrons would flow through the wire?
A ( cdot 2.25 times 10^{22} ) electrons
B. ( 1.13 times 10^{23} ) electrons
C ( cdot 1.01 times 10^{23} ) electrons
D. ( 4.5 times 10^{23} ) electrons
12
411 Which one of the following conditions will increase the voltage of the cell represented by the equation? ( boldsymbol{C u}(s)+mathbf{2 A g}^{+}(boldsymbol{a q} .) rightleftharpoons boldsymbol{C u}^{2+}(boldsymbol{a q} .)+ )
( mathbf{2} boldsymbol{A} boldsymbol{g}(boldsymbol{s}) )
A. Increase in the dimension of ( C u ) electrode
B. Increase in the dimension of ( A g ) electrode
C. Increase in the concentration of ( C u^{2+} ) ion
D. Increase in the concentration of ( A g^{+} ) ion
12
412 The electrode potentials for ( boldsymbol{C u}^{2+}(boldsymbol{a q})+boldsymbol{e}^{-} rightarrow )
( boldsymbol{C u}^{+}(boldsymbol{a q}) ) and ( boldsymbol{C u}^{+}(boldsymbol{a q})+boldsymbol{e}^{-} rightarrow boldsymbol{C u}(boldsymbol{s}) )
are ( +0.15 mathrm{V} ) and +0.50 respectively. The value of ( boldsymbol{E}^{0} boldsymbol{C u}^{2+} mid boldsymbol{C u} ) will be :
A . ( 0.500 mathrm{v} )
B. 0.325
( c .0 .650 v )
D. 0.150
12
413 If a half cell ( boldsymbol{X} mid boldsymbol{X}^{2+}(mathbf{0 . 1} boldsymbol{M}) )
is connected to another half cell
( boldsymbol{Y} mid boldsymbol{Y}^{2+}(mathbf{1} . mathbf{0} boldsymbol{M}) ) by means of ( mathbf{a} )
salt bridge and an external circuit at
( 25^{circ} C, ) the cell voltage would be:
( mathbf{A} cdot 0.06 V )
B. ( 0.12 V )
c. ( 0.62 V )
D. ( 0.72 V )
12
414 Electrolyte ( quad wedge^{infty}left(S c m^{2} m o l^{-1}right) )
( K C l quad 149.9 )
( K N O_{3} )
145.0
( H C l quad 426.2 )
( N a O A c quad 91.0 )
( N a C l quad 126.5 )
Calculate ( Lambda^{infty}_{H O A c} ) using appropriate
molar conductances of the electrolytes
listed above at infinite dilution with ( H_{2} O )
at ( 25^{circ} mathrm{C} ? )
A. 217. 5 ( operatorname{Scm}^{2} ) mol ( ^{-1} )
В. 390.7 ( S c m^{2} ) mol ( ^{-1} )
c. ( 552.7 mathrm{Scm}^{2} mathrm{mol}^{-1} )
D. 517.2 ( S c m^{2} m o l^{-1} )
12
415 Q. 42 When acidulated water (dil. H.SO, solution) is electrolyse
the solution be affected ? Justify your answer.
olutions, pH of the
250, solution) is electrolysed, with pH of
12
416 If ( E_{1}^{o}, E_{2}^{o} ) and ( E_{3}^{o} ) are standard oxidation potentials for ( boldsymbol{F e}left|boldsymbol{F} boldsymbol{e}^{2+}, boldsymbol{F} boldsymbol{e}^{2+}right| boldsymbol{F} boldsymbol{e}^{3+} ) and
( boldsymbol{F} e mid boldsymbol{F} e^{3+}, ) then ( boldsymbol{E}_{3}^{o}=frac{boldsymbol{E}_{2}^{o}+boldsymbol{2} boldsymbol{E}_{1}^{o}}{boldsymbol{n}} . ) The
value of ( n ) is:
12
417 The efficiency of a fuel cell is ( 80 % ) and the standard heat of reaction is
( -300 k J . ) The reaction involves two
electrons in redox change. ( boldsymbol{E}^{ominus} ) for the
cell is:
A . ( 1.24 V )
B . ( 2.48 V )
c. ( 0 V )
D. ( 0.62 V )
12
418 If the solution of the ( C u S O_{4} ) in which
copper rod is immersed in diluted to 10
times, the oxidation electrode potential:
A. increase by 0.030 volt
B. decrease by 0.30 volt
c. increase by 0.059 volt
D. decrease by 0.0059 volt
12
419 State True or False.
In an electrode concentration cell, the
cell reaction ( mathrm{Zn}left(mathrm{C}_{1}right) rightarrow mathrm{Zn}left(mathrm{C}_{2}right) ) will be
spontaneous if ( mathbf{c}_{1}>mathbf{c}_{2} )
A. True
B. False
12
420 The U shaped vessel used in Nelson cell
is lined inside with asbestos which:
A. helps in the separation of cathode and anode compartments
B. acts as an insulator.
C. helps ( H^{+} ) ions to reduced to ( H_{2} ) gas
D. allows the dissociation of steam.
12
421 A dilute aqueous solution of sodium fluoride is electrolyzed, the products at the anode and cathode are:
A. ( O_{2}, H_{2} )
в. ( F_{2}, ) Na
( c cdot O_{2}, N a )
D. ( F_{2}, H_{2} )
12
422 ( boldsymbol{C d}(s)left|boldsymbol{C d C l}_{2}(mathbf{0 . 1 0} boldsymbol{M})right| boldsymbol{A} boldsymbol{g} boldsymbol{C l}(boldsymbol{s}) mid boldsymbol{A} boldsymbol{g}(s )
The EMF of the above cell is 0.6315 V at
( 0^{circ} mathrm{C} ) and ( 0.6753 mathrm{V} ) at ( 25^{circ} mathrm{C} ). The ( Delta H ) of
reaction in ( mathrm{kJ} ) at ( 25^{circ} mathrm{C} ) is:
A . – 176
B. – 234.7
c. 123.5
D . – 167.6
12
423 Explain refining of nicket by mond
process. State kohlarausch’s law
12
424 Assertion: Electrode potential for the
electrode ( M^{n+} mid M ) with concentration
is given by the expression under STP conditions; ( boldsymbol{E}=boldsymbol{E}^{ominus}+frac{mathbf{0 . 0 5 9}}{boldsymbol{n}} log left[boldsymbol{M}^{boldsymbol{n}+}right] )
Reason: STP conditions require the
temperature to be ( 273 mathrm{K} )
A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c. Assertion is true but Reason is false
D. Assertion is false but Reason is true
E. Both Assertion and Reason are false
12
425 The cell EMF is independent of the
concentration of the species of the cell
in:
A ( cdot operatorname{Fe}^{ominus}|operatorname{KOH}(a q)| N i O(s)left|N i_{2} O_{3}(s)right| N i )
B ( cdot P tleft|left(H_{2}right)right| H C l midleft(C l_{2}right) P t )
( mathbf{c} cdot Z nleft|Z n^{2+} | C u^{2+}right| C u )
D. ( H g, H g_{2} C l_{2}left|K C l | A g N O_{3}right| A g )
12
426 Which of the following metal do no
evolve ( boldsymbol{H}_{2} ) gas from dil. acid?
A ( cdot Aleft(E_{A^{+} / A}^{o}=0.25 Vright) )
B ( cdot Bleft(E_{B / B^{+}}^{0}=+0.22 Vright) )
c. ( Cleft(E_{C^{+} / C}^{0}=0.30 Vright) )
D・ ( Dleft(E_{D / D^{+}}^{0}=+0.44 Vright) )
12
427 Solid calcium oxide reacts vigorously with water to form calcium hydroxide accompanied by liberation of heat. This process is called slaking of lime. Which among the following is (are) true about slaking of lime?
(i) It is an endothermic reaction
(ii) It is an exothermic reaction
(iii) The pH of the resulting solution will be more than seven
(iv) The pH of the resulting solution will be less than seven
A ( cdot ) (i) and (ii)
B. (ii) and (iii)
c. (i) and (iv)
D. (iii) and (iv)
12
428 Given,
Question 9. The molar conductivity of 0.025 mol L methanoic acid is
46.1 S cm’ mol-. Calculate its degree of dissociation and dissociation
constant.
2°(H+)= 349.6 S cmmol-1
and
2°(HC00 ) = 54.6 S cm mol-.
(1) Degree of dissociation, a is related to conductivity as a u m
Am is given. Calculate an by using Kohlrausch’s law.
(ii) Calculate K, as Kara and we know Cand a both.
of COOH
12
429 A button cell used in watches functions
as following:
( Z n(s)+A g_{2} O(s)+H_{2} O(l) rightleftharpoons )
( 2 A g(s)+Z n^{2+}(a q)+2 O H^{-}(a q) )
If half cell potentials are:
( Z n^{2+}(a q)+2 e^{-} rightarrow Z n(s) ; E^{circ}= )
( -0.76 V )
( boldsymbol{A} boldsymbol{g}_{2} boldsymbol{O}(boldsymbol{s})+boldsymbol{H}_{2} boldsymbol{O}(boldsymbol{l})+boldsymbol{2} boldsymbol{e}^{-} rightarrow boldsymbol{2} boldsymbol{A} boldsymbol{g}(boldsymbol{s})+ )
( mathbf{2 O H}^{-}(boldsymbol{a q}), boldsymbol{E}^{circ}=mathbf{0 . 3 4} boldsymbol{V} )
The cell potential will be:
A. ( 1.10 v )
B. 0.42
c. ( 0.84 mathrm{v} )
D. 1.34
12
430 Energy efficiency during electroplating is usually in the range:
( A cdot 50 ) to ( 70 % )
B. 80 to 85 %
c. 85 to ( 90 % )
D. 90 to 99 %
12
431 A depolarizer used in dry cell is:
A. ammonium chloride
B. manganese dioxide
C . potassium oxide
D. sodium phosphate
12
432 Q. 16 A, (NH, OH) is equal to ……….
(a) Am (NH4OH) + Am (NH, CI – A (HC) (b) Am (NH, C + Am (NaOH) – NaCl
(c) AM (NH4C) + Am (NaCl) – (NaOH
| (d) Am (NaOH + Am (NaCl) – A (NH, CI)
Thinking Process
This question is based on the concept of Kohlrausch law and can be solved by using the
concept involved in calculation of limiting molar conductivity of any salt. According to
Kohlrausch law limiting molar conductivity of any salt is equal to sum of limiting molar
conductivity of individual molar conductivity of cations and anions of electrolyte.
12
433 The standard reduction potential of
( A g^{+} mid A g ) electrode is 0.80 volt.
Calculate the standard electrode
potential of ( boldsymbol{C l}^{-}|boldsymbol{A} boldsymbol{g} boldsymbol{C l}| boldsymbol{A} boldsymbol{g} ) at ( boldsymbol{2} boldsymbol{5}^{circ} boldsymbol{C} )
Given solubility product, ( boldsymbol{K}_{s p}(boldsymbol{A} boldsymbol{g} boldsymbol{C l})= )
( 1.8 times 10^{-10} )
12
434 Which of the following metals has been used for building boats because it has resistance to corrosion by sea water?
A. copper
B. Nickel
c. Fungsten
D. Titanium
12
435 A decinormal solution of ( A g N O_{3} ) was electrolysed between Pt electrodes. After passing a small current for two hours, a fall of concentration of
0.0005124 equivalent occurred in anodic solution. The mass of copper deposited in copper coulometer placed in series was found to be 0.03879 g.
Find the transport number of ( N O_{3}^{-} ) in
( A g N O_{3} . ) Write answer to the nearest integer after multiplying transport number calculated with 10.
12
436 When an aqueous solution of sodium fluoride is electrolysed, the gas
liberated at anode is ( O_{2} )
If true enter 1 , else enter 0 .
12
437 Formulate a cell from the following electrode reactions:
(a) ( C I_{2(g)}+2 e^{-} longrightarrow 2 C I_{(a q)}^{-} )
( (b) 2 I_{(a q)} longrightarrow I_{2(s)}+2 e^{-} )
12
438 Calculate the solubility product constant of ( A g I ) from the following
values of standard electrode potentials.
( E_{A g^{+} / A g}^{circ}=0.80 ) volt and ( E_{I / A g I / A g}^{circ}= )
-0.15 volt at ( 25^{circ} C )
12
439 In the refining of silver by electrolytic method what will be the weight of 100 g Ag anode if 5 ampere current is passed for 2 hours? Purity of silver is ( 95 % ) by weight. in gram is:
A . 57
B. 32
c. 60
D. 13
12
440 How long (approximate) should water be electrolysed by passing through 100
amperes current so that the oxygen
released can completely burn ( 27.66 g ) of diborane?
(Atomic weight of ( boldsymbol{B}=mathbf{1 0 . 8 u} ) )
A. 3.2 hours
B. 1.6 hours
c. 6.4 hours
D. 0.8 hours
12
441 Kunal took few iron turnings and mixed them well with Sulphur powder. He could separate the iron turnings with the help of a magnet. He heated the
mixture for some time and tried to
separate the iron turnings with the magnet but he could not. Why?
A. on heating, a chemical change takes place and a new compound is formed.
B. on heating, iron becomes non-magnetic hence, it is not attracted by magnettet
c. on heating, a physical change takes place hence iron and Sulphur gets mixed up
D. on heating, iron evaporates and only sulphur is left behind
12
442 Assertion: Rusting of Fe is quicker in saline water than in ordinary water.
Reason: Presence of ( N a^{+} ) and ( C l^{-} ) ions
increase the conductance of the saline
water
A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c. Assertion is true but Reason is false
D. Assertion is false but Reason is true
E. Both Assertion and Reason are false
12
443 ( A g N O_{3}(a q .) ) was added to an aqueous
( K C l ) solution gradually and the
conductivity of the solution was
measured. The plot of conductance ( (wedge) )
versus the volume of ( boldsymbol{A} boldsymbol{g} boldsymbol{N} boldsymbol{O}_{3} )
is
( (mathbf{R}) )
( (mathbf{S}) )
A ( cdot(P) )
B. ( (Q) )
c. ( (R) )
D. ( (S) )
12
444 Saturated solution of ( K N O_{3} ) is used to
make salt bridge because:
A. velocity of ( K^{+} ) ion is greater than that of ( N O_{3}^{-} ) ion
B. velocity of ( N O_{3}^{-} ) ion is greater than that of ( K^{+} ) ion
C. velocities of both ( K^{+} ) and ( N O_{3}^{-} ) ions are nearly the
same
D. ( K N O_{3} ) is highly soluble in water
12
445 How is rust formed? 12
446 Which expression gives the correct
value for the standard potential for a
gold-rhodium voltaic cell?
Half-reaction ( mathbb{E}^{circ}(mathbf{V}) )
( R h_{(q q)}^{+3}+3 e^{-} rightarrow R h_{(s)} )
( A u_{(q q)}^{+}+e^{-} rightarrow A u_{(s)} )
A . ( 1.69 V+0.76 V )
B . ( 1.69 V-0.76 V )
c. ( 3(1.69) V+0.76 V )
D. ( 3(1.69) V-0.76 V )
12
447 The specific conductance of a saturated solution of AgCl in water is ( 1.826 times ) ( 10^{-6} Omega^{-1} mathrm{cm}^{-1} ) at ( 25^{circ} mathrm{C} ) calculate its
solubility in water at ( 25^{circ} mathrm{C} )
Given that ( :-lambda^{circ}left(A g^{+}right)=61.92 )
[
boldsymbol{lambda}^{circ}left(mathbf{C l}^{-}right)=mathbf{7 6 . 3 4}
]
12
448 For cell reaction ( : Z n+C u^{2+} rightarrow Z n^{2}+ )
( C u ) cell representation is:
A ( cdot Z nleft|Z n^{2+} | C u^{2+}right| C u )
в. ( C uleft|C u^{2+} | Z n^{2+}right| Z n )
c. ( C uleft|Z n^{2+}right||Z n| C u^{2+} )
D. ( C u^{2+}left|Z n | Z n^{2+}right| C u )
12
449 0.59 Assertion (A) A, for weak electrolytes shows a sharp increase when the
electrolytic solution is diluted.
Reason (R) For weak electrolytes degree of dissociation increases with
dilution of solution.
12
450 The concentration of ( K^{+} ) in interior and
exterior of a Nerve cell are ( 500 mathrm{mM} ) and
( 25 mathrm{mM} ) respectively. The electrical potential (in volt) that exists across the
membrane is : ( left[log _{10} 2=right. ) ( mathbf{0 . 3}, mathbf{2 . 3 0 3} boldsymbol{R} boldsymbol{T} / boldsymbol{F}=mathbf{0 . 0 6}] ) (Given answer
be multiplying with 1000)
12
451 When the power delivered by a 100 volt battery is 40 watts, the equivalent resistance of the circuit is:
A. 100 ohms
B. 250 ohms
c. 300 ohms
D. 350 ohms
12
452 When lead storage battery is charged:
A. lead dioxide dissolves
B. sulphuric acid is regenerated
C. lead electrode becomes coated with lead sulphate
D. the concentration of sulphuric acid decreases
12
453 Question 15. A solution of Ni(NO3)2 is electrolysed between platinum
electrodes using a current of 5 amperes for 20 min. What mass of Ni is
deposited at the cathode? (Atomic mass of Ni= 58.7)
W (0) Find the quantity of electricity used by the formula, Q = i xt.
Feb (1) Write the balance equation for the electrolysis of Ni(NO3), to find the
quantity of electricity used to deposit 1 mole (58.7 g mol-‘) Ni.
(iii) Apply the mole concept for calculating the mass of Ni.
.
12
454 When 4.0 A of current is passed through a ( 1.0 mathrm{L}, 0.10 mathrm{M} F e^{3+}(a q) ) solution for 1.0
hour, it is partly reduced to ( mathrm{Fe}(mathrm{s}) ) and partly of ( boldsymbol{F e}^{2+}(boldsymbol{a q}) ). The correct statements(s) is/are:
This question has multiple correct options
A. 0.10 mol of electrons are required to convert all ( F e^{3} )
to ( F e^{2+} )
B. 0.025 mol of Fe(s) will be deposited.
c. 0.075 mol of iron remains as ( F e^{2+} )
D. 0.050 mol of iron remains as ( F e^{2+} )
12
455 The two aqueous solutions; ( boldsymbol{A}left(boldsymbol{A} boldsymbol{g} boldsymbol{N} boldsymbol{O}_{3}right) )
and ( boldsymbol{B}(boldsymbol{L} boldsymbol{i} boldsymbol{C l}) ) were electrolysed using
Pt electrodes. The pH of the resulting solutions will :
A. increase in A and decrease in B
B. decrease in both
c. increase in both
D. decrease in A and increase in B
12
456 For a reaction, ( boldsymbol{A}(boldsymbol{s})+mathbf{2} boldsymbol{B}^{+} rightarrow boldsymbol{A}^{2+}+ )
( 2 B, K_{c} ) has been found to be ( 10^{12} ). The
( boldsymbol{E}_{c e l l}^{o} ) is:
A. ( 0.138 V )
( V )
в. ( 0.235 mathrm{V} )
c. ( 0.354 V )
D. none of these
12
457 Electrolysis of sea-water produces
( C l_{2}(g) ) at the anode by the oxidation of
Cl (aq) ions. What volume of the gas will be produced at STP by current of ( 1.50 mathrm{A} ) applied for 90.0 minutes?
B. 0.548 L
c. ( 0.94 mathrm{L} )
D. 0.470 L
12
458 A hydrogen electrode placed in a buffer
solution of ( mathrm{CH}_{3} mathrm{COONa} ) and acetic acid
in the ratio’s ( x: y ) and ( y: x ) has reduction electrode potential values ( mathrm{E}_{1} ) volt and ( mathrm{E}_{2} )
volt respectively at ( 25^{circ} mathrm{C} ). The ( mathrm{pK}_{a} ) values
of acetic acid is ( left(mathrm{E}_{1} text { and } mathrm{E}_{2} ) are oxidation right.
potential):
A. ( frac{E_{1}+E_{2}}{0.118} )
в. ( frac{E_{2}-E_{1}}{0.118} )
c. ( -frac{E_{1}+E_{2}}{0.118} )
D. ( -frac{E_{2}-E_{1}}{0.118} )
12
459 The term used to indicate the
development of unpleasant smell and taste in fat and oil-containing foods due to aerial oxidation is:
A . acidity
B. radioactivity
c. rabidity
D. rancidity
12
460 The specmc conductances in oh ( m^{-1} c m^{-1} ) of four electrolytes
( P, Q, R ) and ( S ) are given in brackets:
( Pleft(5.0 times 10^{-5}right) )
( Qleft(7.0 times 10^{-8}right) )
( boldsymbol{R}left(mathbf{1} . mathbf{0} times mathbf{1 0}^{-mathbf{1 0}}right) )
( boldsymbol{S}left(boldsymbol{9} cdot boldsymbol{2} times mathbf{1} boldsymbol{0}^{boldsymbol{3}}right) )
The one that offers highest resistance to the passage of electric current is:
A . ( P )
в. ( Q )
( c . s )
D. ( R )
12
461 At infinite dilution stage, the solution of
( C H_{3} C O O H ) in water does not contain :
A. ( H^{+} ) ion
в. ( C H_{3} C O O^{-} ) ion
c. ( C H_{3} C O O H ) molecule
D. all of these
12
462 (A) Define the following terms:
(i) Limiting molar conductivity
(ii) Fuel cell
(B) Resistance of a conductivity cell filled with 0.1 mol ( L^{-1} ) KCl solution is
100Omega. If the resistance of the same cell
when filled with 0.02 mol ( L^{-1} ) KCl
solution is ( 540 Omega ), calculate the
conductivity and molar conductivity of 0.02 mol ( L^{-1} K C l ) solution. The
conductivity of 0.1 mol ( L^{-1} ) KCl solution is ( 1.29 times 10^{-2} Omega^{-1} mathrm{cm}^{-1} )
12
463 Select the correct statements about
galvanic cells.
This question has multiple correct options
A. Electrons are fed into anode by the oxidation reaction that takes place at the electrode.
B. The anode pushes these electrons into the external circuit and thus, acts as a source of negative charge.
C. The cathode acts as an electron sink and thus, called positive electrode.
D. The algebraic sum of E ( _{O P} ) of anode and E ( _{O P} ) of cathode gives the +ve value for spontaneous process.
12
464 The maximum work that can be
obtained from the cell
( boldsymbol{A l}left|boldsymbol{A l}^{3+}(mathbf{0 . 1} boldsymbol{M}) | boldsymbol{F} boldsymbol{e}^{boldsymbol{2}+}(boldsymbol{0 . 2} boldsymbol{M})right| boldsymbol{F e} ) is:
( left[text { Given }: boldsymbol{E}_{A l^{3+} / A l}^{o}=-mathbf{1 . 6 6} mathbf{V} ) and right.
( left.boldsymbol{E}_{boldsymbol{F} e^{2+} / boldsymbol{F} e}^{boldsymbol{o}}=-mathbf{0 . 4 4} boldsymbol{V}right] )
A. ( 605.8 mathrm{kJ} )
B. 505.8 kJ
c. 705.8 kJ
D. 905.8 kJ
12
465 Given ( : boldsymbol{H}_{2} boldsymbol{O}_{2} rightarrow boldsymbol{O}_{2}+boldsymbol{2} boldsymbol{H}^{oplus}+boldsymbol{2} boldsymbol{e}^{-} )
( boldsymbol{E}^{ominus}=-mathbf{0 . 6 9} boldsymbol{V} )
( boldsymbol{H}_{2} boldsymbol{O}_{2}+boldsymbol{2} boldsymbol{H}^{oplus}+boldsymbol{2} boldsymbol{e}^{-} rightarrow boldsymbol{2} boldsymbol{H}_{2} boldsymbol{O} )
( boldsymbol{E}^{ominus}=mathbf{1 . 7 7} boldsymbol{V} )
( boldsymbol{I}^{ominus} rightarrow+mathbf{2} e^{-} )
( boldsymbol{E}^{ominus}=-mathbf{0 . 5 3 5} boldsymbol{V} )
Which of the following statements is / (are) correct?
This question has multiple correct options
( mathbf{A} cdot H_{2} O_{2} ) behaves as an oxidant for ( I_{2} / I^{ominus} )
B. ( H_{2} O_{2} ) behaves as an reductant for ( I_{2} / I^{ominus} )
C ( cdot I^{ominus} / I_{2} ) behaves as an reductant for ( H_{2} O_{2} )
D. None of these is correct.
12
466 Assertion: It is safe to stir ( 1 mathrm{M} A g N O_{3} )
solution with a copper spoon.
[
begin{aligned}
text { Reason: } boldsymbol{E}_{boldsymbol{A} boldsymbol{g} oplus mid boldsymbol{A} boldsymbol{g}}^{ominus} &=mathbf{0 . 8 0} boldsymbol{V} \
boldsymbol{E}_{boldsymbol{C u}^{2+} mid boldsymbol{C u}}^{ominus} &=mathbf{0 . 3 4} boldsymbol{V}
end{aligned}
]
A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c. Assertion is true but Reason is false
D. Assertion is false but Reason is true
E. Both Assertion and Reason are false
12
467 In a dry cell containing a
moist paste of plaster of Paris, ( boldsymbol{N} boldsymbol{H}_{4} boldsymbol{C l} )
and ( Z n C l ) acts as
A. copper vessel, Cathode
B. zinc vessel, Cathode
c. zinc vessel, Anode
D. copper vessel, Anode
12
468 The apparatus in which electrical energy is converted into chemical
energy is known as:
A. voltameter
B. coulometer
( c cdot operatorname{both}(A) ) and ( (B) )
D. none of these
12
469 Resistance of ( 0.2 M ) solution of an
electrolyte is ( 50 Omega ). The specific
conductance of the solution is ( 1.4 S )
( m^{-1} . ) The resistance of ( 0.5 M ) solution
of the same electrolyte is ( 280 Omega ). The molar conductivity of ( 0.5 ~ M ) solution of
the electrolyte in ( S m^{2} m o l^{-1} ) is:
A ( .5 times 10^{3} )
В . ( 5 times 10^{2} )
c. ( 5 times 10^{-4} )
D. ( 5 times 10^{-3} )
12
470 In an experiment set up for the measurement of EMF of a half cell using reference electrode and a salt bridge, when the salt bridge is removed, the voltage:
A. Does not change
B. Increase to maximum
c. Decreases to half the value
D. Drops to zero
12
471 In corrosion of iron,
A. electrons flow from anode to cathode through the metal, while ions flow through the water droplets
B. an electrochemical (galvanic) cell is formed in which ( F e ) acts as anode and ( O_{2} ) is reduced at cathode
C ( . ) dissolved ( O_{2} ) oxidizes ( F e^{2+} ) to ( F e^{3+} ) before it is
deposited as rust ( left(F e_{2} O_{3} cdot x H_{2} Oright) )
D. All of the above takes place
12
472 Among ( N a, H g, S, P t, ) and graphite which can be used as electrodes
in electrolytic cell having aqueous solutions ?
A. ( N ) aand ( S )
в. ( H g, P t ), and ( S )
c. ( N a, H g ), and ( S )
D. ( H g, P t ), and graphite
12
473 For an electrochemical reaction
occuring in a galvanic cell. ( mathbf{2} boldsymbol{F} boldsymbol{e}_{(boldsymbol{a q})}^{+mathbf{3}}+boldsymbol{Z} boldsymbol{n}_{(s)} rightarrow boldsymbol{Z} boldsymbol{n}_{(a q)}^{+2}+mathbf{2} boldsymbol{F} boldsymbol{e}_{(a q)}^{+mathbf{2}} )
if concentration of ( F e^{+2} ) is increased.
A. ( E_{text {cll}} ) will remain unchanged
B. ( E_{text {cll}} ) will decrease
c. ( p H ) of the solution will change
D. less non P-V work will be obtained
12
474 On passing a current through molten KCI ( 19.5 mathrm{g} ) of ( mathrm{K} ) is deposited. The amount of ( mathrm{Al} ) deposited by the same quantity of electricity if passed through molten AlCl
is :
A. ( 4.5 mathrm{g} )
B. ( 9.0 mathrm{g} )
c. ( 13.5 mathrm{g} )
D. 27 g
12
475 Acidified water is electrolysed by using carbon electrodes.What is produced at negative carbon electrode? 12
476 An alloy weighing 1.05 g of ( P b-A g ) was dissolved in desired amount of
( H N O_{3} ) and the volume was made 350
( mathrm{mL} . ) An ( mathrm{Ag} ) electrode was dipped in
solution and ( E_{text {cell}} ) of the cell
K. The percentage of lead in alloy is (divide answer by 25 ) :
Given: ( boldsymbol{E}_{A boldsymbol{g}^{+} / boldsymbol{A} boldsymbol{g}}^{o}=mathbf{0 . 8 0} boldsymbol{V} )
12
477 In passing ( 3 mathrm{F} ) of electricity through three electrolytic cells connected in
series containing ( boldsymbol{A} boldsymbol{g}^{oplus}, boldsymbol{C} boldsymbol{a}^{2+}, boldsymbol{a} boldsymbol{n} boldsymbol{d} boldsymbol{A} boldsymbol{l}^{3} )
ions, respectively. The molar ratio in
which the three metal ions are liberated
at the electrode is:
A. 1: 2: 3
B . 2: 3: 1
c. 6: 3: 2
D. 3: 4: 2
12
478 During the electrolysis of the aqueous solution of copper sulphate using Pt electrodes, the reaction taking place at
anode electrode is:
A ( cdot C u^{2+}+2 e^{-} rightarrow C u )
в. ( C u rightarrow C u^{2+}+2 e^{-} )
( mathbf{c} cdot 2 H_{2} O rightarrow 4 H^{+}+O_{2}+4 e^{-} )
” ( quad H_{2} O+e^{-} rightarrow O H^{-}+frac{1}{2} H_{2} )
12
479 Write Nernst equation for Daniel cell at
equilibrium condition and derive
relationship between ( E_{(text {cell})}^{o} ) and
equilibrium constant ( left(boldsymbol{K}_{c}right) )
12
480 Which of the following electrolytic solutions has the least specific
conductance?
A. ( 0.002 mathrm{N} )
N ( mathrm{N} ) N ( . .0000 )
B. ( 0.1 N )
c. ( 0.2 N )
D. ( 2 N )
12
481 Using Pt electrodes same quantity of electricity is passed in ( mathbf{0 . 0 3} M A I C I_{3}, 0.01 M A I C I_{3}, 0.01 M A g )
solutions. If 0.36 g silver is deposited what is the mass of Al deposited in two
( A I C I_{3} ) solutions and volume of ( O_{2} )
evolved at STP in NaOH solution?
12
482 The technique of protecting a metal from
corrosion by connecting it to a second metal (that is more easily oxidized) is
called:
A. galvanization
B. anodic protection
C . cathodic protection
D. sacrificial protection
12
483 Give equations for the racharging of a
lead storage battery.
12
484 What is molar conductivity? How is it
related to the concentration of
electrolyte?
12
485 Peroxodisulphate salts (e.g., ( N a_{2} S_{2} O_{8} ) ) are
strong oxidizing agents used as bleaching agents for fats, oils, etc. Given :
( O_{2}(g)+4 H^{oplus}(a q)+4 e^{-} rightarrow 2 H_{2} O(l) )
( E^{ominus}=1.23 V )
( S_{2} O_{8}^{2-}(a q)+2 e^{-} rightarrow S O_{4}^{2-}(a q) )
( E^{ominus}=2.01 V )
Which of the following statements is (are) correct?
This question has multiple correct options
A. Oxygen gas can oxidize sulphate ion to per-oxo disulphate ion ( left(S_{2} O_{8}^{2-}right) ) in acidic solution
в. ( O_{2}(g) ) is reduced to water
c. water is oxidized to ( O_{2} )
D. ( S_{2} O_{8}^{2-} ) ions are reduced to ( S O_{4}^{2-} ) ions
12
486 The amount of chlorine evolved by
passing 2 A of current in an aqueous solution of ( N a C l ) for 30 minutes is:
A. 2.648
в. ( 1.32 mathrm{g} )
c. ( 3.62 g )
D. ( 4.22 mathrm{g} )
12
487 The bulb does not glow in the set up
shown in the figure. List the possible
reasons. Explain your answer.
12
488 Equivalent conductance and molar
conductance of ( boldsymbol{F e}_{2}left(boldsymbol{S} boldsymbol{O}_{4}right)_{3} ) are related
by relation:
( mathbf{A} cdot wedge_{e}=Lambda_{m} )
B ( cdot wedge_{e q}=frac{Lambda_{m}}{3} )
( mathbf{C} cdot wedge_{e q}=3 wedge_{m} )
D ( cdot wedge_{e q}=frac{Lambda_{m}}{6} )
12
489 os
0.27 For the given cell, Mg Mg2+ || Cu2+ Cu
(a) Mg is cathode
(b) Cu is cathode
(c) The cell reaction is Mg + Cu2+ Mg2+ + Cu
(d) Cu is the oxidising agent
12
490 While charging the lead storage battery,
This question has multiple correct options
( mathbf{A} cdot P b S O_{4} ) on anode is reduced to ( P b )
B. ( P b S O_{4} ) on cathode is reduced to ( P b )
( mathrm{C} cdot P b S O_{4} ) on cathode is oxidised to ( P b )
D. ( P b S O_{4} ) on anode is oxidised to ( P b O_{2} )
12
491 In cell representation, oxidation half cell is represented on the:
A. Ieft hand side
B. right hand side
c. salt bridge
D. none of the above
12
492 At ( p H=3 ) and rest all reductant and oxidant in change (I) being in standard
state, ( M n O_{4}^{-} ) can oxidise:
A ( cdot I^{-} ) and ( B r^{-} ) both
B. ( I^{-} ) and ( C l^{-} ) both
c. ( I^{-}, B r^{-} ) and ( C l^{-} ) all
D. ( B r^{-} ) and ( C l^{-} ) both
12
493 Which statements about conductivity
of distilled water are correct?
This question has multiple correct options
A. It possesses almost non-conducting nature
B. It is obtained by distillation of water several times
C. It is contaminated with little acid
D. None of the above
12
494 Question 14. When acidulated water (dil. H2SO4 solution) is
electrolysed, will the pH of the solution be affected? Justify your answer.
12
495 Assertion
In a Daniell cell, if the concentration of
( C u^{2+} ) and ( Z n^{2+} ) ions are doubled, the
EMF of the cell will be doubled.
Reason
f the concentration of ions in contact
with metals is doubled, the electrode
potential is doubled.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
496 (a) Write Faraday’s second law of
electrolysis
(b) Draw labelled diagram of standard Hydrogen electrode
12
497 Give reasons.
( boldsymbol{E}^{o} ) value for ( boldsymbol{M} boldsymbol{n}^{3+} / boldsymbol{M} boldsymbol{n}^{2+} ) couple is
much more positive than that for ( boldsymbol{F} boldsymbol{e}^{boldsymbol{3}+} / boldsymbol{F} boldsymbol{e}^{boldsymbol{2}+} )
12
498 Time required to deposit one millimole of aluminium metal by the passage of
9.65 amperes through aqueous solution of aluminium ion is :
A . ( 30 s )
в. ( 10 s )
c. ( 30,000 s )
D. ( 10,000 s )
12
499 Find the mass of silver deposited when
a current of 1.5 ampere is passed through silver nitrate solution for 5 min. (Atomic mass of ( A g ) is 108 g)
12
500 A hydrogen gas. electron is made by dipping platinum wire in a solution of ( H C I ) of ( p H=10 ) and by passing hydrogen gas around the platinum wire at one atm pressure.The oxidation potential of electrode would be?
A . ( 1.18 V )
в. ( 0.059 V )
c. ( -0.59 V )
D. ( 0.118 mathrm{V} )
12
501 Through a solution of ( C u S O_{4}, ) a current
of 3 amperes was passed for 2 hours. At cathode, ( 3 g ) of ( C u^{2+} ) ions were discharged. The current efficiency is :
[At. wt. of ( boldsymbol{C u}=mathbf{6 3 . 5} ) ]
A . ( 33.3 % )
B . ( 42.2 % ) %
c. ( 48.7 % )
D . 54.4 %
12
502 Q Type your question
“I 11
( left.sqrt{boldsymbol{c}}(text {in } boldsymbol{m o l} / boldsymbol{L})^{1 / 2}right) ) for ( boldsymbol{K} boldsymbol{C l} ) solution?
( left(boldsymbol{y}=wedge_{m} ; boldsymbol{x}=sqrt{boldsymbol{c}}right) )
( A )
B.
( c )
( D )
12
503 Theoretical efficiency of fuel cell is:
A. nearly ( 60 % )
B. 50%
c. ( 33 % )
D. nearly 100%
12
504 Resistance of a conductivity cell filled
with 0.15 mol ( L^{-1} ) NaCl solution is ( 50 Omega )
If resistance of the same cell when filled
with 0.02 mol ( L^{-1} ) NaCl solution is 500
( Omega, ) calculate the conductivity of 0.02
mol ( L^{-1} ) NaCl solution. (The
conductivity of 0.15 mol ( L^{-1} ) NaCl solution is ( 1.5 mathrm{s} / mathrm{m} ) ).
12
505 Consider the reaction,
( mathbf{2} boldsymbol{A} boldsymbol{g}^{+}+boldsymbol{C} boldsymbol{d} rightarrow boldsymbol{2} boldsymbol{A} boldsymbol{g}+boldsymbol{C} boldsymbol{d}^{2} )
The standard electrode potentials for
( A g^{+} rightarrow A g ) and ( C d^{2+} rightarrow C d ) couples
are 0.80 volt and -0.40 volt
respectively.
(i) What is the standard potential ( E^{circ} ) for
this reaction?
(ii) For the electrochemical cell, in
which this reaction takes place which electrode is negative electrode?
12
506 Which of the following has the highest molar conductivity under similar conditions?
A. Diamminedichloroplatinum (II)
B. Tetraamminedichlorocobalt (III) Chloride
c. Potassium hexacyanoferrate (II)
D. Hexaaquachromium
(III) chloride
12
507 Q. 25 Conductivity k, is equal to………
(6)
(c) Am
RA
(a) 1 1
12
508 Assertion
The electrolysis of potassium iodide, ( mathrm{K} ) I produces electrical energy.
Reason
Electrolytic cells convert chemical energy into electrical energy
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
509 At ( 25^{circ} C, ) the standard oxidation
potential of ( Z n ) and ( A g ) in water are:
( Z n(s) rightarrow Z n^{+2}(a q)+2 e^{-}, E^{0}= )
( 0.76 V )
and ( A g(s) rightarrow A g^{+}(a q)+e^{-}, E^{0}= )
( -0.80 V )
Which of the following reaction actually takes place?
A ( cdot Z n^{2+}(a q)+2 A g(s) rightarrow 2 A g^{+}(a q)+Z n(s) )
B. ( Z n(s)+2 A g^{+}(a q) rightarrow Z n^{2+}(a q)+2 A g(s) )
C. ( Z n^{2+}(a q)+2 A g^{+}(a q) rightarrow Z n(s)+2 A g(s) )
D. ( Z n(s)+A g(s) rightarrow Z n^{2+}(a q)+A g^{+}(a q) )
12
510 An electric charge of 5 Faraday’s is passed through three electrolytes
( A g N O_{3}, C u S O_{4} ) and ( F e C l_{3} ) solution
The grams of each metal liberated at cathode will be:
A. ( A g=10.8 g, C u=12.7 g, F e=1.11 g )
в. ( A g=540 g, C u=367.5 g, F e=325 g )
c. ( A g=108 g, C u=63.5 g, F e=56 g )
D. ( A g=540 g, C u=158.8 g, F e=93.3 g )
12
511 In a galvanic cell, the salt bridge
(i) does not participate chemically in the cell reaction
(ii) stops the diffusion of ions from one electrode to another
(iii) is necessary for the occurrence of the cell reaction
(iv) ensures mixing of the two electrolytic solutions.
A. (i) and (iii) only
B. (i) and (ii) only
c. (iii) and (iv) only
D. All of these
12
512 An acidic solution of ( C u^{2+} ) salts
containing ( 0.4 mathrm{g} ) of ( C u^{2+} ) is electrolyzed until all the copper is deposited. The electrolysis is continued for seven more
minutes with the volume of solution
kept at ( 100 mathrm{mL} ) and the current at ( 1.2 mathrm{A} ) The volume (in ( mathrm{mL} ) ) of gases evolved at STP during the entire electrolysis is :
(write your answer to nearest integer)
12
513 The conductivity ( left(operatorname{in} Omega^{-1} m^{-1}right) ) of
( K_{2} S O_{4} ) solution is: ( ( ) write your answer to nearest integer)
12
514 Define : Standard electrode potential. 12
515 Calculate the ( p H ) at which the potential
of hydrogen electrode will be ( 0.059 V )
12
516 (A) 1 faraday ( =96,500 ) coulomb. It is a charge of 1 mole electrons.
(R) 1 faraday charge liberates one gram equivalent of substance at an electrode.
A. Both (R) and (A) are true and reason is the. correct explanation of assertion
B. Both (R) and (A) are true but reason is not correct explanation of assertion
c. Assertion
(A) is true but reason
(R) is false
D. Assertion
(A) and reason
(R) both are false
E. Assertion (A) is false but reason (R) is true
12
517 A half cell reaction is one which:
A. involves only half a mole of electrolyte
B. goes only half way to completion
C. takes place at one electrode
D. consumes half a unit of electricity
12
518 (a) What do you understand by corrosion?
(b) Write electro-chemical theory of corrosion (Rust).
(c) Write prevention (two) of corrosion.
12
519 Q. 66 Consider the figure and answer the following questions.
Salt bridge
Zinc
plate
& Zn² (aq)
Copper plate
& Cu²+ (aq)
Cell A
lectrode
(A) Electrode
Electrolytic
cell
Cell B
(i) Cell A has Ecell = 2V and Cell ‘B’ has E cell = 1.1V which of the two cells
A’ or ‘B’ will act as an electrolytic cell. Which electrode reactions will
occur in this cell?
(ii) If cell A has E cell = 0.5V and cell ‘B’ has E cell = 1.1V then what will be
the reactions at anode and cathode?
Thinking Process
This problem includes concept of electrochemical cell, electrolytic cell and charge on
electrode. To solve this problem identify the charge on each electrode first
12
520 The potential across the metal and the aqueous solution of its ions of unit
activity at ( 298 mathrm{K} ) is known as:
A . electrode potential
B. standard electrode potential
c. formal electrode potential
D. oxidation potential
12
521 Iron is not protected from rusting by:
A. galvanization
B. electroplating with ( N i ) or ( C r )
C. heating the iron to redness in steam
D. treating it with ( H_{3} P O_{4} )
12
522 The specific conductance of a ( 0.1 mathrm{N} mathrm{KC} ) solution is 0.012 ohm ( ^{-1} c m^{-1} ). The
resistance of the cell containing the
same solution is 55 ohms. Then the
cell constant is :
( begin{array}{lll}text { A } cdot 0.918 & c m^{-1}end{array} )
B. ( 0.66 mathrm{cm}^{-1} )
( begin{array}{lll}text { C } cdot & 1.142 & c m^{-1}end{array} )
D. 1.12 cm ( ^{-1} )
12
523 The reduction potential of hydrogen
half-cell will be negative if:
( mathbf{A} cdot mathrm{p}left(mathrm{H}_{2}right)=1 ) atom and ( left[mathrm{H}^{+}right]=2.0 mathrm{M} )
( mathbf{B} cdot mathbf{p}left(mathbf{H}_{2}right)=1 ) atm and ( left[mathrm{H}^{+}right]=1.0 mathrm{M} )
( mathbf{C} cdot mathrm{p}left(mathrm{H}_{2}right)=2 mathrm{atm} ) and ( left[mathrm{H}^{+}right]=1.0 mathrm{M} )
( mathbf{D} cdot mathrm{p}left(mathrm{H}_{2}right)=2 mathrm{atm} ) and ( left[mathrm{H}^{+}right]=2.0 mathrm{M} )
12
524 Typical battery used is the mercury cell, which is used in?
A . Electric watches
B. Television sets
c. Radio transistors
D. Electric torches
12
525 Cell constant of a conductivity cell is:
A. specific conductance / resistance
B. specific conductance ( times frac{1000}{text { Normality }} )
c. specific conductance / conductance
D. conductance / specific conductance
12
526 0.58 Assertion (A) Conductivity of all electrolytes decreases on dilution.
Reason (R) On dilution number of ions per unit volume decreases.
12
527 toppr ( = )
Q Type your question
( A )
B.
( c )
( D )
12
528 Assertion
Molar conductivity increases with
decrease in concentration.
Reason
Conductivity always decreases with
decrease in concentration.
A. Both Assertion and Reason are correct and Reason is
the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
529 Molar conductivity ( left(lambda_{M}right) ) and equivalent
conductivity ( left(lambda_{e q}right) ) for an electrolyte
( A_{x} B_{y} ) at any dilution are related as:
A ( . lambda_{M}=lambda_{e q} . times(x+y) )
B . ( lambda_{M}=lambda_{e q} ). ( times x times y )
c. ( lambda_{M}=frac{lambda_{e q}}{x+y} )
D. ( lambda_{M}=frac{lambda_{e q}}{x times y} )
12
530 The ( E_{M^{3+} / M^{2+}}^{0} ) values of ( mathrm{Cr}, mathrm{Mn}, mathrm{Fe} ) and
Co are ( -mathbf{0 . 4 1},+mathbf{1 . 5 7},+mathbf{0 . 7 7} ) and
( +1.97 mathrm{V} ) respectively. For which one of these metals the change in oxidation
state from +2 to +3 is easiest?
A ( . C r )
в. ( M n )
c. ( F e )
D. ( C o )
12
531 What will be the volume of ( O_{2} ) at N.T.P
liberated by 5 A current flowing for 193 s through acidulated water?
( mathbf{A} cdot 56 mathrm{m} )
B. ( 112 mathrm{ml} )
c. ( 158 mathrm{ml} )
D. 965 ml
12
532 During the working of the cell:
( boldsymbol{P b}- )
( boldsymbol{H} boldsymbol{g}(mathbf{1} . boldsymbol{0} boldsymbol{M})left|boldsymbol{P} boldsymbol{b}^{2+}(boldsymbol{a} boldsymbol{q})(boldsymbol{1} boldsymbol{M})right| boldsymbol{P} boldsymbol{b}^{2+}(boldsymbol{a} boldsymbol{q})(mathbf{1} )
( boldsymbol{H} boldsymbol{g}(mathbf{0 . 5} boldsymbol{M}) )
This question has multiple correct options
( mathbf{A} cdotleft[P b^{2+}right] ) in right half cell decreases
B ( cdotleft[P b^{2+}right] ) in left half cell decreases
c. ( left[P b^{2+}right] ) does not change in either of the half cells
D. molarity of lead amalgam in right half cell increases while that of left half cell decreases
12
533 The standard reduction potential of metals ( X, Y ) and ( Z ) are ( -0.403 vee, 0.337 V ) and ( 0.79 mathrm{V} ) respectively. Which of the following reaction is not possible?
A ( cdot X+H_{2} S O_{4} rightarrow X S O_{4}+H_{2} )
в. ( 2 Z+2 H N O_{3} rightarrow 2 Z N O_{3}+H_{2} )
c. ( Y+Z_{S} O_{4} rightarrow Y S O_{4}+2 Z )
D. ( X+2 Z N O_{3} rightarrow Xleft(N O_{3}right)_{2}+2 Z )
12
534 How many faradays are required to reduce one mole of ( M n O_{4}^{ominus} ) to ( M n^{2+} ? )
( mathbf{A} cdot mathbf{1} )
B. 2
( c .3 )
D.
12
535 Among the four successive members of the first series of the transition metals
listed below in the options, which one has a positive standard potential ( left(boldsymbol{E}_{M^{2+} / M}^{0}right) ) value?
A. ( N i(Z=28) )
в. ( C u(Z=29) )
c. ( F e(Z=26) )
D. ( operatorname{Co}(Z=27) )
12
536 What is the value of ( Delta S^{ominus} ) for the fuel
cell at ( 25^{circ} C ) ?
В. ( -160 J K^{-1} )
c. ( 160 J K^{-1} )
D. ( 1600 J K^{-1} )
12
537 The molar conductivities of ( wedge_{N a O A c}^{circ} ) and ( wedge_{H C l}^{circ} ) at infinite dilution in water at
( 25^{circ} mathrm{C} ) are 91 and ( 426.2 S mathrm{cm}^{2} mathrm{mol}^{-1} )
respectively. To calculate, ( wedge_{H O A c}^{circ}, ) the additional value required
is
( mathbf{A} cdot wedge_{H_{2} O}^{circ} )
в. ( wedge_{K C l}^{circ} )
c. ( wedge_{N a O H}^{circ} )
( mathbf{D} cdot wedge_{N a C l}^{circ} )
12
538 Which of the following is always true regarding the spontaneity of reaction occuring in a galvanic cell?
A ( cdot E^{0}_{c e l l}>0, Delta G^{0}K_{c} )
B . ( E^{0}_{c e l l}>0, Delta G^{0}<0 ) and ( Q0, Delta G^{0}>0 ) and ( Q>K_{c} )
D . ( E^{0}_{c e l l}>0, Delta G^{0}>0 ) and ( Q<K_{c} )
12
539 Metals react differently with water. The more vigorous is the reaction, the more
is the bubble formation. The following
diagram illustrates the reaction of sodium, magnesium and copper with
water.
What can be concluded from this
diagram?
A. Magnesium reacts more vigorously with water than sodium and copper
B. Sodium reacts more vigorously with water than magnesium and copper.
c. Sodium reacts more vigorously than copper but less vigorously than magnesium.
D. copper reacts more vigorously with water than sodium and magnesium.
12
540 In a galvanic cell electrical energy is generated at the expense of chemical
energy. If true enter 1 , else enter 0
12
541 To liberate ( 5.4 mathrm{g} ) of silver (atomic mass 108 amu) from an aqueous solution of sliver nitrate, it is required to pass:
A. 965C of electricity
B. 4825C of electricity
c. ( 9650 mathrm{c} ) of electricity
D. ( 48250 mathrm{c} ) of electricity
12
542 An oxide of iron from the following is:
A. mud
B. dust
c. rust
D. none of these
12
543 ( Z n(s) / Z n^{2+}(a q) | C u^{2+}(a q) / C u(s) )
( boldsymbol{E}^{0} z n^{2+} / Z n=-0.76 mathrm{V} )
( boldsymbol{E}^{0}_{C u^{2+} / C u}=+0.34 mathrm{V} )
Calculate ( boldsymbol{E}_{c e l l}^{0} ) and equilibrium
constant ( boldsymbol{K} )
12
544 The molar conductivity of a
( 0.5 m o l / d m^{3} ) solution of ( A g N O_{3} ) with electrolytic conductivity of ( 5.76 times ) ( 10^{-3} operatorname{Scm}^{-1} ) at ( 298 K ) is:
A ( .2 .88 S mathrm{cm}^{2} / mathrm{mol} )
B . ( 11.52 mathrm{S} mathrm{cm}^{2} / mathrm{mol} )
c. ( 0.086 S mathrm{cm}^{2} / mathrm{mol} )
D. ( 28.8 S mathrm{cm}^{2} / mathrm{mol} )
12
545 Two weak acid solutions ( H A_{1} ) and ( H A_{2} )
each with the same concentration and
having pKa values 3 and 5 are placed in contact with hydrogen electrode ( (1 mathrm{atm} ) ( 25^{0} C ) ) and are interconnected through a salt bridge. Find emf of the cell.
A ( .+0.059 mathrm{V} )
B. 0.059
c. ( 0.0295 mathrm{v} )
D. 0.118 V
12
546 Solution ( A, B ) and ( C ) of the same strong electrolyte offered resistances of
( 50 Omega, 100 Omega, ) and ( 150 Omega ) in a given conductivity cell. The resistance observed if they are mixed in a volume proportion which is reciprocal of their resistances and tested in the same
conductivity cell would be:
A . ( 67.3 Omega )
B. ( 81.8 Omega )
c. ( 100 Omega )
D. ( 300 Omega )
12
547 Question 4. Calculate the potential of hydrogen electrode in
contact
with a solution whose pH is 10.
(i) Since, pH is given, calculate Ht from the relation [H* ] = 1×107
(ii) Then, calculate Et by using Nernst equation as EiH+ /V2H) IS
taken as 0.00 V.
12
548 The highest electrical conductivity of the following aqueous solutions is of
A. ( 0.1 M ) acetic acid
B. ( 0.1 M ) chloroacetic acid
c. ( 0.1 M ) fluoroacetic acid
D. ( 0.1 M ) difluoroacetic acid
12
549 Find the equilibrium constant for the reaction, ( boldsymbol{F e}^{2+}+boldsymbol{C e}^{4+} rightleftharpoons boldsymbol{F e}^{3+}+boldsymbol{C e}^{3+} )
( left[text { Given: } boldsymbol{E}_{C e^{4+} / C e^{3+}}^{o}=right. )
( left.mathbf{1} . mathbf{4 4} boldsymbol{V} ; boldsymbol{E}_{boldsymbol{F e}^{3+} / mathbf{F e}^{mathbf{2 +}}}^{boldsymbol{o}}=mathbf{0 . 6 8} boldsymbol{V}right] )
A . ( 7.6 times 10^{12} )
B . ( 5.4 times 10^{12} )
c. ( 3.3 times 10^{12} )
D. None of the above
12
550 Determine the standard reduction
potential for the half reaction:
( boldsymbol{C l}_{2}+boldsymbol{2} boldsymbol{e}^{-} longrightarrow boldsymbol{2} boldsymbol{C l}^{-} )
Given: ( boldsymbol{P} boldsymbol{t}^{2}+boldsymbol{2} boldsymbol{C l} longrightarrow boldsymbol{P} boldsymbol{t}+ )
( boldsymbol{C l}_{2}, boldsymbol{E}_{c e l l}^{0}=-mathbf{0 . 1 5} boldsymbol{V} )
( boldsymbol{P t}^{2}+boldsymbol{2} boldsymbol{e}^{-} longrightarrow boldsymbol{P t}, boldsymbol{E}^{0}=mathbf{1 . 2 0} boldsymbol{V} )
12
551 The standard electrode potentials
( left(boldsymbol{E}_{boldsymbol{M}^{+} / M}^{o}right) ) of four metals ( mathbf{A}, mathbf{B}, mathbf{C} ) and ( mathbf{D} )
are ( -1.2 vee, 0.6 vee, 0.85 mathrm{V} ) and ( -0.76 mathrm{V} )
respectively. The increasing sequence of deposition of metals on applying potential is :
( A cdot A, C, B, D )
B. B, D, C, A
c. ( c, B, D, A )
D. D, A, B, C
12
552 A solution of metal salt was electrolyzed
with a current of 0.1 A for 160 minutes.
Ni deposited at cathode was found 0.2950 g.
What is the charge on metal ion? (Atomic mass of metal is 58.71 )
12
553 Assertion
The electrical resistance of any object decreases with increase in its length.
Reason
Electrical resistance of any object
increases with increase in its area of
cross-section.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
554 Question 3. Consult the table on standard electrode potentials and
suggest three substances that can oxidise ferrous ions under suitable
condition.
12
555 At ( 298 K, ) given that:
[
begin{array}{c}
boldsymbol{C u}(boldsymbol{s})left|boldsymbol{C} boldsymbol{u}^{2+}(mathbf{1} . boldsymbol{0} boldsymbol{M}) | boldsymbol{A} boldsymbol{g}^{+}(mathbf{1} . boldsymbol{0} boldsymbol{M})right| boldsymbol{A} boldsymbol{g}(boldsymbol{s}) \
boldsymbol{E}_{c e l l}^{o}=mathbf{0 . 4 6} boldsymbol{V} \
boldsymbol{Z} boldsymbol{n}(boldsymbol{s})left|boldsymbol{Z} boldsymbol{n}^{2+}(mathbf{1} cdot mathbf{0} boldsymbol{M}) | boldsymbol{C} boldsymbol{u}^{2+}(mathbf{1} . boldsymbol{0} boldsymbol{M})right| boldsymbol{C} boldsymbol{u} \
boldsymbol{E}_{text {cell }}^{o}=mathbf{1 . 1 0} boldsymbol{V}
end{array}
]
Then, the ( E_{text {cell}} ) for the following reaction
at ( 298 K ) will be:
[
boldsymbol{Z} boldsymbol{n}(boldsymbol{s})left|boldsymbol{Z} boldsymbol{n}^{2+}(boldsymbol{0} cdot boldsymbol{1} boldsymbol{M}) | boldsymbol{A} boldsymbol{g}^{+}(mathbf{1} cdot boldsymbol{0} boldsymbol{M})right| boldsymbol{A} boldsymbol{g}(s
]
A . ( 1.56 V )
в. ( 1.53 V )
( mathbf{c} .2 .53 V )
D. cannot be calculated due to insufficient data
12
556 ( C H_{3} C O O H ) is titrated with NaOH
solution. Which of the following
statement is true?
A. conductance increases upto equivalence point, after which it decreases.
B. Conductance decreases upto equivalence point, after which it increases.
c. conductance first increases (but not rapidly) upto equivalence point and then increases rapidly after equivalence point.
D. none
12
557 Na is used in reduction of ( Z n ) salt
because:
A ( cdot E Z n(o x i)>E N a(o x i) )
B . ( E Z n(r e d)<E N a(r e d) )
C. ( E Z n(o x i)<E N a(o x i) )
D. Both (A) and (B)
12
558 Resistance and conductivity of a cell containing ( 0.001 mathrm{M} ) KCl solution at 298
( mathrm{K} ) are ( 1500 Omega ) and ( 1.46 times 10^{-4} mathrm{S.cm}^{-1} )
respectively. What is the cell constant?
( mathbf{A} cdot 0.219 mathrm{cm}^{-1} )
B. ( 0.319 mathrm{cm}^{-1} )
c. ( 0.419 c m^{-1} )
D. None of these
12
559 • 2 Electrode potential for Mg electrode varies according to the equation
Ema 2+ Mg = 5Mg 2+/Mg
0.059 log 1. The graph of EMg2+ /Mg
2 9[Mg2+]
vs log [Mg2+ ] is
Emg2*/Mg
EMg? Mg
EMg2+/Mg
EMq2*/Mg
log[Mg2+1 log[Mg2+) → log[Mg2+1 log[Mg2+1
Thinking Process
This problem includes concept of Nernst equation and its transformation to equation of
straight line
12
560 Which of the following statement is
correct?
A. Cathode is negative terminal both in galvanic and electrolytic cells
B. Anode is positive terminal both in galvaniv and electrolytic cells
C. Cathode is negative terminal in an electrolytic cell whereas anode is negative terminal in a galvanic cell
D. Anode is negative terminal in an electrolytic cell whereas cathode is positive terminal in galvanic cell
12
561 What are ‘fuel cells’? Write cathode and
anode reaction in a fuel cell.
12
562 Any article of iron if left in open for some
time, acquires a film of brownish
substance (rust) having chemical formula:
( mathbf{A} cdot F e_{3} O_{4} )
в. ( F e_{2} O_{3} )
c. Feo
D. ( operatorname{Fe}(O H)_{2} )
12
563 The following two redox reactions are
given:
¡) ( M n O_{4}^{-}+8 H^{+}+5 e^{-} rightarrow M n^{2+}+ )
( mathbf{4} boldsymbol{H}_{2} boldsymbol{O} ; boldsymbol{E}^{boldsymbol{o}}=boldsymbol{X}_{mathbf{1}} boldsymbol{V} )
ii) ( boldsymbol{M} boldsymbol{n} boldsymbol{O}_{2}+boldsymbol{4} boldsymbol{H}^{+}+boldsymbol{2} boldsymbol{e}^{-} rightarrow boldsymbol{M} boldsymbol{n}^{2+}+ )
( mathbf{2} boldsymbol{H}_{2} boldsymbol{O} ; boldsymbol{E}^{o}=boldsymbol{X}_{2} boldsymbol{V} )
Find ( E^{o} ) for the following reaction.
( M n O_{4}^{-}+4 H^{+}+3 e^{-} rightarrow M n O_{2}+ )
( 2 H_{2} O )
A. ( X_{2}-X_{1} )
В. ( X_{1}-X_{2} )
c. ( frac{5 X_{1}-2 X_{2}}{3} )
D. ( frac{2 X_{1}-5 X_{2}}{3} )
12
564 For the reaction ( boldsymbol{A}+mathbf{2} boldsymbol{B}^{+} rightleftharpoons boldsymbol{A}^{2+}+ )
( 2 B ; K_{c} ) has been found to be ( 10^{12} ). The
( boldsymbol{E}_{c e l l}^{o} ) is:
A . 0.354
в. 0.708
c. ( 0.0098 mathrm{v} )
D. 1.36 ( v )
12
565 The quantity of electricity required to reduce 12.3 g of nitro benzene to aniline assuming 50% current efficiency is:
( A cdot 115800 C )
B. 57900 C
c. 231600 ( c )
D. 28950 C
12
566 During electrolysis of ( 1 mathrm{L}, 1 mathrm{M} ) AgNO ( _{3} ) using silver electrodes, 9.65 A current is used for one hour. Assuming the volume to remain unchanged, the molarity of
( A g N O_{3} ) at the end of the electrolytic
process is :
A. 1 м
B. 0.36 м
c. 0.64 М
D. None of these
12
567 Aluminium oxide may be electrolysed
at ( 1000^{circ} mathrm{C} ) to furnish aluminium metal.
The cathode reaction is ( A l^{3+}+3 e^{-} rightarrow )
Al. To prepare ( 5.12 mathrm{kg} ) of aluminium
metal by this method would require:
A ( cdot 5.49 times 10^{1} C ) of electricity
B . ( 5.49 times 10^{4} C ) of electricity
c. ( 1.83 times 10^{7} C ) of electricity
D. ( 5.49 times 10^{7} C ) of electricity
12
568 Which of the following statement is
correct?
( mathbf{A} cdot E_{text {cell}} ) and ( triangle_{r} G ) of cell reaction both are extensive
properties
B. ( E_{text {cell}} ) and ( triangle_{r} G ) of cell reaction both are intensive
properties
C. ( E_{text {cell}} ) in the intensive property while ( triangle_{r} G ) of cell reaction is an extensive property.
D. ( E_{text {cell}} ) in the intensive property while ( triangle_{r} G ) of cell reaction is an intensive property.
12
569 Which of the following represents
increasing order of ionic conductance?
( mathbf{A} cdot F^{-}<C l^{-}<B r<I^{-} )
B ( cdot I^{-}<B r^{-}<F^{-}<C l^{-} )
( mathbf{c} cdot F^{-}<C l^{-}<I^{-}<B r^{-} )
D ( cdot F^{-}<I^{-}<C l^{-}<B r^{-} )
12
570 An examples of a simple fuel cell is:
A. lead storage battery
в. ( H_{2}-O_{2} ) cell
c. daniell cell
D. lechlanche cell
12
571 To carry out the so-called electrolysis of
water, sulphuric acid is added to water. How does the addition of sulphuric acid produce a conducting solution?
12
572 ( H C l ) can be used to remove rust from
iron.
A. True
B. False
12
573 The STP volume of oxygen liberated by 2 ampere of current when passed through acidulated water for 3 minutes and 13
seconds, is:
A . 120 ( c c )
B. 22.4 cc
c. ( 11.2 mathrm{c} )
D. 44.8 сс
12
574 ( ln H_{2}-O_{2} ) fuel cell, the reaction
occurring at cathode is :
( mathbf{A} cdot 2 H_{2(g)}+O_{2(g)} rightarrow 2 H_{2} O_{(l)} )
B. ( O_{2(g)}+2 H_{2} O_{(l)}+4 e^{-} longrightarrow 4 O H_{(a q)}^{-} )
( ^{mathrm{c}} cdot H^{+}+e^{-} rightarrow frac{1}{2}^{H}_{2} )
( mathbf{D} cdot H_{(a q)}^{+}+O H_{(a q)}^{-} longrightarrow H_{2} O_{(l)} )
12
575 Assertion
Galvanic cell convert chemical energy into electrical energy.
Reason
Redox reactions are those in which
oxidation takes place at anode and reduction at cathode.
A. If both Assertion and Reason are correct and Reason is the correct explanation of assertion
B. If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion
C. If Assertion is correct but Reason is incorrect
D. If Assertion is incorrect but Reason is correct
12
576 At ( 298 K, ) the equilibrium constant for the reaction
( Z n^{2+}+4 N H_{3} rightleftharpoonsleft[Z nleft(N H_{3}right)_{4}right]^{2} ) is ( 10^{circ} )
If ( boldsymbol{E}_{left[Z nleft(N H_{3}right)^{4}right]^{2} /left[Z n, 4 N H_{3}right]}=-1.03 V ) then
the value of ( E_{Z n / Z n^{2+}}^{o} ) will be:
A. ( -0.7654 V )
в. ( -1.1 V )
c. ( +1.1 V )
D. none of these
12
577 The ionic conductances of ( A l^{3+} ) and
( boldsymbol{S} boldsymbol{O}_{3}^{2-} ) ions at infinite dilution are ( boldsymbol{x} ) and ( y ) oh ( m^{-1} c m^{2} m o l^{-1} ) respectively. If
Kohlrausch’s law is valid, then molar
conductance of aluminium sulphate at infinite dilution will
be
A ( .3 x+2 y )
в. ( 3 y+2 x )
( c cdot 2 x+2 y )
D. ( 3 x+3 y )
12
578 If a monovalent metal ion carries ( 1.6 times )
( 10^{-19} ) coulomb of electricity, what is the
amount of electricity carried by one gram molecular mass of the metal
ions?
( mathbf{A} cdot 9.6336 times 10^{4} )coulomb
B. ( 10.6336 times 10^{4} ) coulomb
c. ( 95.336 times 10^{4} ) coulomb
D. ( 96.336 times 10^{4} ) coulomb
12
579 For a cell reaction involving two electron
changes, ( boldsymbol{E}_{c e l l}^{0}=mathbf{0 . 3} boldsymbol{V} ) at ( mathbf{2 5}^{circ} boldsymbol{C} ). The
equilibrium constant of the reaction is:
( mathbf{A} cdot 10^{-10} )
В. ( 3 times 10^{-2} )
c. 10
D. ( 10^{10} )
12
580 The main factors which affect corrosion
are :
A. Position of metal in electrochemical series
B. Presence of ( C O_{2} ) in water
c. Presence of impurities coating
D. All are correct
12
581 Write the complete chemical reaction of rusting of iron. 12
582 What is a secondary cell? 12
583 The cathode in the central compartment of Castner Kellner cell used for the
manufacture of ( N a O H ) is:
A. Iron
B. Carbon
C. Mercury
D. Steel
12
584 Standard free energies of formation(in
( k J / m o l ) ) at ( 298 mathrm{K} ) are -237.2,-394.4
and -8.2 for ( H_{2} O(I), C O_{2}(g) ) and pentane(g) respectively. The value of ( E_{c e l l}^{o} ) for the pentane-oxygen fuel cell is:
A . ( 1.968 mathrm{v} )
в. 2.0968 V
c. ( 1.0968 mathrm{v} )
D. ( 0.0968 mathrm{V} )
12
585 Write the cell reaction and calculate ( boldsymbol{E}^{o} )
cell of the following electrochemical
cell:
( boldsymbol{A} boldsymbol{l}left|boldsymbol{A} boldsymbol{l}^{3+} | boldsymbol{Z} boldsymbol{n}^{2+}right| boldsymbol{Z} boldsymbol{n} )
( (boldsymbol{s})(boldsymbol{a q} cdot) )
[
begin{array}{c}
(mathbf{1} boldsymbol{M})(mathbf{1} boldsymbol{M}) \
boldsymbol{E}_{boldsymbol{A} l}^{o}=-mathbf{1 . 6 6 V} \
boldsymbol{E}_{Z n}^{o}=-mathbf{0 . 7 6 V}
end{array}
]
12
586 Identify the electrolyte which deposits maximum amount of cathodic product for the passage of 1 faraday of electricity.
A. ( F e C l_{2} )
B. FeBr ( _{3} )
c. ( A g N O_{3} )
D. ( C u S O_{4} )
12
587 The standard reduction potential of ( boldsymbol{C u}^{2+} / boldsymbol{C u} ) couple is ( mathbf{0 . 3 4} mathrm{V} ) at ( mathbf{2 5}^{mathbf{0}} mathrm{C} )
Calculate the reduction potential at
( boldsymbol{p} boldsymbol{H}=mathbf{1 4} ) for this couple.
( operatorname{Given} boldsymbol{K}_{s p} ) of ( boldsymbol{C u}(boldsymbol{O H})_{2}=mathbf{1 . 0} times mathbf{1 0}^{-mathbf{1 8}} mathbf{)} )
12
588 Assertion
faraday is the charge that liberates 1 eq. of metal at cathode.
Reason
Passsage of 1 faraday charge through
aq. ( mathrm{MgCl}_{2} ) liberates 12 g Mg at cathode.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
589 What is anodising? Give its
applications.
12
590 A button cell used in watches functions
as following:
( boldsymbol{Z n}(s)+boldsymbol{A g}_{2} boldsymbol{O}(s)+boldsymbol{H}_{2} boldsymbol{O}(l) rightleftharpoons )
( 2 A g(s)+Z n^{2+}(a q)+2 O H^{-}(a q) )
f half cell potentials are: ( Z n^{2+}(a q)+ )
( 2 e rightarrow Z n(s) ; E^{0}=-0.76 V )
( A g_{2} O(s)+H_{2} O(l) 2 e rightarrow 2 A g(s)+ )
( mathbf{2} boldsymbol{O} boldsymbol{H}^{-}(boldsymbol{a} boldsymbol{q}), boldsymbol{E}^{0}=mathbf{0} . boldsymbol{3} mathbf{4} boldsymbol{V} )
The cell potential will be:
A . ( 1.10 V )
B. ( 0.42 V )
c. ( 0.84 V )
D. ( 1.34 V )
12
591 Write the equations for the reactions taking place at anode and cathode in lead storage cell. 12
592 How many electrons flow through a
metallic wire if a current of ( 0.5 A ) is
passed for 2 hours? (Given : ( 1 F= )
( left.mathbf{9 6}, mathbf{5 0 0} boldsymbol{C} boldsymbol{m o l}^{-mathbf{1}}right) )
12
593 Assertion
Statement-I: If an aqueous solution of NaCl is electrolysed, the product
obtained at the cathode is ( H_{2} ) gas and
not Na.
Reason
Statement-II : Gases are liberated faster
than the metals.
A. Statement-l is true, Statement-II is true; Statement-II is correct explanation for Statement-I
B. Statement-lis true, Statement-II is true; Statement-II is NOT a correct explanation for statement-
c. Statement-I is true, Statement-II is false
D. Statement-I is false, Statement-II is true
12
594 When the liquid between two ends allow
electric current, then :
A. bulb of tester glows
B. only heating of the tester takes place
c. bulb of the tester does notglow
D. none of the above
12
595 Presence of ( mathrm{CO}_{2} ) in natural water
facilitate rusting of iron.
If true enter 1 , else enter 0
12
596 A reversible galvanic cell is connected to an external battery. If the EMF of the battery is less than the EMF of the galvanic cell, then the current:
A. will not pass through the circuit
B. will flow from the battery to the galvanic cell
c. will flow from the galvanic cell to the battery
D. can flow in any direction
12
597 Question 12. How much charge is required for the following reductions:
(i) 1 mole of A13+ to AIP
(ii) 1 mole of Cu4+ to Cup
(iii) 1 mole of MnO4 to Mn2+?
Write electrode reaction (balanced), to find the number of electron taking
part in the reaction and then calculate Q by using,
Q = n <96500 C.
12
598 When one faraday of electric current is passed, the mass deposited is equal to:
A. one gram equivalent
B. one gram mole
c. electrochemical equivalent
D. half gram equivalent
12
599 Which among the following equations represents the reduction reaction taking place in lead accumulator at positive electrode, while it is being used as a source of electrical energy?
( mathbf{A} cdot P b rightarrow P b^{2} )
B. ( P b^{4+} rightarrow P b )
( mathbf{c} cdot P b^{2+} rightarrow P b )
D. ( P b^{4+} rightarrow P b^{2} )
12
600 For ( boldsymbol{Z} boldsymbol{n}^{2+} / boldsymbol{Z} boldsymbol{n}, boldsymbol{E}^{boldsymbol{o}}= )
( -0.76 V, ) for ( A g^{+} / A g, E^{o}=0.799 V )
The correct statement is :
A. the reaction ( Z n ) getting reduced ( A g ) getting oxidized is spontaneous
B. ( Z n ) undergoes reduction and ( A g ) is oxidized
C. ( Z n ) undergoes oxidation and ( A g^{+} ) gets reduced
D. no suitable answer
12
601 Does pure water conduct electricity?
A. Yes
B. No
c. Sometimes
D. None of above
12
602 LED stands for:
A. light emitting diode
B. loose emitting diode
C . light emission device
D. light emitting device
12
603 Which of the following reactions is correct for a given electrochemical cell
( operatorname{at} 25^{circ} C ? )
( boldsymbol{P t}left|boldsymbol{B r}_{2}(boldsymbol{g})right| boldsymbol{B r}^{-}(boldsymbol{a q}) | boldsymbol{C l}^{-}(boldsymbol{a q}) mid boldsymbol{C l}_{2}(boldsymbol{g}) )
A ( cdot 2 B r^{-}(a q)+C l_{2}(g) rightarrow 2 C l^{-}(a q)+B r_{2}(g) )
B . ( B r_{2}(g)+2 C l^{-}(a q) rightarrow 2 B r^{-}(a q)+C l_{2}(g) )
C. ( B r_{2}(g)+C l_{2}(g) rightarrow 2 B r^{-}(a q)+2 C l^{-}(a q) )
D ( cdot 2 B r^{-}(a q)+2 C l^{-}(a q) rightarrow B r_{2}(g)+C l_{2}(g) )
12
604 Question 2. Can Ecell or A,G°for cell reaction ever be equal to zero? 12
605 Which of the following is disposable
battery?
A. Lead acid battery
B. Mercury cell
c. ( N i-C d ) battery
D. None of these
12
606 I. Conductance of electrolyte solution increases with temperature.
II. Resistivity is reciprocal of molar conductivity of electrolyte.
III. Cell constant has unit ( c m^{-1} )
Which of the above statements are
correct?
A. All the statements are correct
B. II and III are correct
c. I and III are correct
D. Only II is correct
12
607 A current of ( 19.3 mathrm{mA} ) is passed for 9375 seconds through ( 500 mathrm{ml} ) of ( 2 mathrm{mM} )
( Z n S O_{4} ) solution. If the final molarity of
( Z n^{2+} ) is ( 0.5 mathrm{mM} ), then the current efficiency of the source is (assume volume remains constant during this process):
A . 80%
B. 75%
c. 72%
D. 65%
12
608 A battery of e.m.f. E and internal
resistance ( r ) is connected to an external
resistance ( R ) the condition for
maximum power transfer is
A. $$ldisplaystyler
в. ( r>R )
c. ( r=1 / R )
( mathbf{D} cdot r=R )
12
609 Electrolyte ( quad K C l quad K N O_{3} ) ( boldsymbol{H} C l )
[
begin{array}{ll}
Lambda_{left(S c m^{2}right.}^{Lambda infty}_{left.m o l^{-1}right)}^{infty} & 149.9
end{array}
]
( 426 . )
Calculate ( Lambda^{infty}_{H O A c} ) using appropriate molar conductances of the electrolytes
listed above at infinite dilution in ( boldsymbol{H}_{2} boldsymbol{O} )
( operatorname{at} 25^{circ} C )
( mathbf{A} cdot 517.2 )
B. 552.7
c. 390.7
D. 217.5
12
610 During charging of lead accumulator?
A. concentration of ( H_{2} S O_{4} ) decreases
B. specific gravity of ( H_{2} S O_{4} ) increases
( mathrm{C} cdot P b mathrm{O}_{2} ) dissolves in electrolyte
D. lead is deposited at positive terminal
12
611 In the electrochemical cell
( H_{2}(g), 1 a t mleft|H^{+}(1 M)right|left|C u^{2+}(1 M)right| C u(s) )
which one of the following is the correct value of reduction potential?
A . ( 1.10 mathrm{V} )
B. 0.110
c. ( 1.50 mathrm{v} )
D. 0.220
12
612 The conductivity of 0.001028 mol ( L^{-1} )
acetic acid is ( 4.95 times 10^{-5} mathrm{Scm}^{-1} )
Calculate its dissociation constant if
( boldsymbol{Lambda}_{mathbf{m}}^{mathbf{o}} ) for ( mathbf{3} mathbf{9 0 . 5} mathbf{S} mathbf{c m}^{2} mathbf{m o l}^{-mathbf{1}} )
12
613 Solutions which are decomposed due to
the current passed through them are called
12
614 Define corrosion. What is meant by
rust? Write the chemical formula of
rust.
12
615 The equivalent conductance at infinite
dilution of ( B a C l_{2}, H_{2} S O_{4} ) and ( H C l )
aqueous solutions are ( x_{1}, x_{2} ) and ( x_{3} )
respectively. The equivalent
conductance of ( B a S O_{4} ) solution is:
A. ( x_{1}+x_{2}-x_{3} )
В. ( x_{1}-x_{2}-x_{3} )
c. ( x_{1}+x_{2}-2 x_{3} )
D. ( x_{1}-2 x_{2}-x_{3} )
12
616 Which one is correct about a
hypothetical electrochemical cell shown
below?
( underset{A}{Theta}left|boldsymbol{A}^{+}(boldsymbol{X} boldsymbol{M}) | boldsymbol{B}^{+}(boldsymbol{Y} boldsymbol{M})right| underset{boldsymbol{B}}{oplus} boldsymbol{E}_{c e l l}= )
( +0.20 V )
A. The cell reaction cannot be predicted
B . ( A+B^{+} rightarrow A^{+}+B )
( mathbf{c} cdot A^{+}+B rightarrow A+B^{+} )
D. ( A^{+}+e rightarrow A ; B^{+}+e rightarrow B )
12
617 The emf of the cell involving the following reaction, ( 2 A g^{+}+H_{2} longrightarrow )
( 2 A g+2 H^{+} ) is 0.80 volt. The standard
oxidation potential of silver electrode is:
B. ( 0.50 mathrm{v} )
c. ( -0.30 v )
D. ( 0.40 mathrm{v} )
12
618 ( boldsymbol{E}_{c e l l}^{o}=boldsymbol{E}_{O boldsymbol{P}}^{o}+boldsymbol{E}_{R P}^{o} ) if two electrodes are
connected.
If true enter 1 , else enter 0 .
12
619 The specific conductivity of a saturated
solution of silver chloride is ( 2.30 times )
( 10^{-6} ) mho ( c m^{-1} ) at ( 25^{circ} C . ) Calculate the
solubility of silver chloride at ( 25^{circ} mathrm{C} ) if
( lambda_{A g^{+}}=61.9 m h o c m^{2} m o l^{-1} ) and
( boldsymbol{lambda}_{C l^{-}}=mathbf{7 6 . 3} boldsymbol{m h o c m}^{2} boldsymbol{m o l}^{-1} )
12
620 Which of the following represents the
oxidation half-reaction for the
unbalanced redox equation?
( boldsymbol{C u}+boldsymbol{H} boldsymbol{N} boldsymbol{O}_{3} rightarrow boldsymbol{C u}left(boldsymbol{N} boldsymbol{O}_{3}right)_{2}+boldsymbol{N} boldsymbol{O}_{2} )
A ( cdot C u^{2+}+2 e^{-} rightarrow C u )
в. ( C u rightarrow C u^{2+}+2 e^{-} )
c. ( N O_{3}^{-} rightarrow N O_{2}+1 e )
D. ( 2 H^{+}+N O_{2}^{-}+1 e^{-} rightarrow N O_{2}+H_{2} O )
12
621 Calculate the mass and volume at NTP
of hydrogen and chlorine that will be formed by passing 10,000 coulomb of charge through an aqueous solution of potassium chloride. The cell reaction is:
( 2 K C l+2 H O H rightarrow 2 K O H+C l_{2}+ )
( boldsymbol{H}_{2} )
12
622 Write the cell reaction and calculate the
emf of the cell
( boldsymbol{P t}left|boldsymbol{H}_{2}(boldsymbol{g}, mathbf{1} boldsymbol{a} boldsymbol{t m})right| boldsymbol{H}^{+}(mathbf{0 . 5} boldsymbol{M}) | boldsymbol{K} boldsymbol{C l}(mathbf{1} boldsymbol{M}) )
( operatorname{at} 25^{circ} C, E=0.28 V )
12
623 ( boldsymbol{A} boldsymbol{g} mid boldsymbol{A} boldsymbol{g}^{oplus}(boldsymbol{1} boldsymbol{M})left|boldsymbol{A} boldsymbol{g}^{oplus}right| boldsymbol{A} boldsymbol{g} )
( 0.5 F ) electricity in this LHS (anode) and
1 F of electricity in the RHS (cathode) is first passed making them independent electrolytic cells at ( 298 mathrm{K} ). EMF of the cell after electrolysis will be:
A. increased
B. remain same
c. decreased
D. None of these
12
624 0.52 Match the items of Column I and Column II.
Column
Column II
A. Lead storage battery 1. Maximum efficiency
B. Mercury cell
2. Prevented by galvanisation
C Fuel cell
3. Gives steady potential
D. Rusting
4. Pb is anode, Pbo, is cathode
12
625 ( boldsymbol{N} boldsymbol{i}left|boldsymbol{N} boldsymbol{i}^{2+} | boldsymbol{C} boldsymbol{u}^{2+}right| boldsymbol{C} boldsymbol{u} )
The standard EMF of the above cell is
( 0.59 mathrm{V} . ) The standard electrode potential (reduction potential) of the copper electrode is 0.34 V. Calculate the
standard electrode potential of nicke
electrode.
A . ( -0.5 V )
B. ( 0.25 V )
c. ( 0.93 V )
D. – ( 0.25 V )
12
626 On passing 0.01 Faraday of elctricity through a solution of aluminum chloride, the weight of Aluminium metal (at.wt. ( =mathbf{2 7} ) ) deposited on
cathode is:
( mathbf{A} cdot 0.9 g m )
В. ( 0.09 g m )
c. ( 2.7 g m )
D. ( 0.27 g m )
12
627 Is the reaction, ( 2 A l+3 F e^{2+} rightleftharpoons )
( 2 A l^{3+}+2 F e ) possible?
A. No, because standard oxidation potential of ( A lF e )
c. cannot be predicted
D. Yes, because aluminium is a strong oxidising agent
12
628 Electrochemical cells are also called:
This question has multiple correct options
A. electrolytic cells
B. galvanic cells
c. fuel cells
D. voltaic cells
12
629 Which of the following shows maximum molar conductance?
A ( cdotleft[operatorname{Co}left(N H_{3}right)_{6}right] C l_{3} )
В ( cdotleft[operatorname{Co}left(N H_{3}right)_{3} C l_{3}right] )
c. ( left[operatorname{Co}left(N H_{3}right)_{4} C l_{2}right] C l )
D ( cdotleft[operatorname{Co}left(N H_{3}right)_{5} C lright] C l_{2} )
12
630 Calomel is:
A ( . H g_{2} C l_{2} )
в. ( mathrm{HgCl}_{2} )
( mathrm{c} . H g_{2} C l_{2}+H g )
D. ( H g+H g C l_{2} )
12
631 What will be the molar conductivity of
( A l^{3+} ) ions at infinite dilution if molar
conductivity of ( A l_{2}left(S O_{4}right)_{3} ) is ( 858 S c m^{2} ) ( m o l^{-1} ) and ionic conductance of ( S O_{4}^{2-} )
is 160 S ( c m^{2} ) mol ( ^{-1} ) at infinite dilution?
A ( cdot 189 mathrm{S} mathrm{cm}^{2} mathrm{mol}^{-1} )
B. ( 698 mathrm{S} mathrm{cm}^{2} mathrm{mol}^{-1} )
c. ( 1018 mathrm{s} mathrm{cm}^{2} mathrm{mol}^{-1} )
D. ( 429 mathrm{S} mathrm{cm}^{2} mathrm{mol}^{-1} )
12
632 Which of the following is/are correct about 1 mole electrons?
This question has multiple correct options
A . ( 6.023 times 10^{23} ) electrons
В . ( 5.48 times 10^{-7} mathrm{kg} )
c. 96500 coulomb charge
D. None of these
12
633 According to Kohlrausch law, the limiting value of molar conductivity of
an electrolyte ( boldsymbol{A}_{2} boldsymbol{B} )
( mathbf{A} cdot lambda_{A^{+}}+lambda_{B^{2}} )
в. ( frac{1}{2} lambda_{A+}+lambda_{B^{2}} )
c. ( _{2 lambda_{A^{+}}+frac{1}{2} lambda_{B^{2}}} )
D. ( 2 lambda_{A^{+}}+lambda_{B^{2}} )
12
634 Electrolytic reduction of alumina to
aluminium by Hall-Heroult process is carried out:
A. in the presence of Nacı
B. in the presence of fluoride
c. in the presence of cryolite which forms a melt with lower melting temperature.
D. in the presence of cryolite which forms a melt with higher melting temperature
12
635 Two platinum electrodes were
immersed in a solution of ( C u S O_{4} ) and
electric current was passed through the solution. After some time, it was found
that colour of ( C u S O_{4} ) disappeared with evolution of gas at the electrode. The colorless solution contains:
A. Platinum sulphate
B. Copper hydroxide
c. copper sulphate
D. Sulphuric acid
12
636 Question 9. The resistance of a conductivity cell containing 0.001 M
KCI solution at 298 K is 1500S2. What is the cell constant if conductivity of
0.001 M KCl solution at 298 K is 0.146 x 10-3 S cm-1.
Cell constant = Conductivity < Resistance
12
637 Which of the following has the highest molar conductivity in solution?
( mathbf{A} cdotleft[P tleft(N H_{3}right)_{6}right] C l_{4} )
в. ( left[P tleft(N H_{3}right)_{5} C lright] C l_{3} )
( mathbf{c} cdotleft[operatorname{Pt}left(N H_{3}right)_{4} C l_{2}right] C l_{2} )
D ( cdotleft[operatorname{Pt}left(N H_{3}right)_{3} C l_{3}right] C l )
12
638 Whats the potential of the reaction below given the half-reaction potentials:
( 2 F e_{2}++C l_{2} rightarrow 2 F e^{3+}+2 C l^{-} )
( boldsymbol{F} boldsymbol{e}^{boldsymbol{3}+}+boldsymbol{e}^{-} rightarrow boldsymbol{F} boldsymbol{e}^{2+} ; boldsymbol{E}=mathbf{0 . 7 7} boldsymbol{V} )
( boldsymbol{C l}_{2}+mathbf{2} boldsymbol{e}^{-} rightarrow mathbf{2} boldsymbol{C l}^{-} ; boldsymbol{E}=mathbf{1 . 3 6} boldsymbol{V} )
A . ( 0.18 V )
B . ( 0.59 V )
c. ( 1.05 V )
D. ( 2.13 V )
E ( .2 .90 V )
12
639 If a piece of iron gains ( 10 % ) of its weight
due to partial rushing into ( F e_{2} O_{3} ) the
percentage of total iron that has rusted is:
A . 23
B. 13
c. 23.3
D. 90
12
640 Number of coulombs required to deposit ( 90 g ) of ( A l ) when the electrode
reaction ( A l^{3+}+3 e rightarrow A l ) is
A ( cdot 9.65 times 10^{6} )
B. ( 8.685 times 10^{4} )
c. ( 9.65 times 10^{4} )
D. 6.955
12
641 What is the amount of chlorine evolved
when 2 ampere of current is passed for
30 minutes in an aqueous solution of
NaCl?
A ( .66 g )
в. ( 1.32 g )
( mathrm{c} cdot 33 mathrm{g} )
D. ( 99 g )
12
642 Units of the properties measured are given. Which of the properties has not been matched correctly?
A. Molar conductance ( =mathrm{S} m^{2} m o l^{-1} )
B. Cell constant ( =m^{-1} )
C. Specific conductance ( =mathrm{S} m^{2} )
D. Equivalent conductance ( =operatorname{Sm}^{2}(g e q)^{-1} )
12
643 Calculate the cell potential (in V) if ( triangle G=-96.5 k J / m o l ) and ( n=1 ) 12
644 Given below are the half-cell reactions:
( M n^{2+}+2 e^{-} rightarrow M n ; E^{0}=-1.18 V )
( mathbf{2}left(boldsymbol{M} boldsymbol{n}^{3+}+boldsymbol{e}^{-} rightarrow boldsymbol{M} boldsymbol{n}^{2+}right) ; boldsymbol{E}^{0}= )
( +1.51 V )
The ( boldsymbol{E}^{0} ) for ( boldsymbol{3} boldsymbol{M} boldsymbol{n}^{2+} rightarrow boldsymbol{M} boldsymbol{n}+boldsymbol{2} boldsymbol{M} boldsymbol{n}^{3+} )
will be:
A. ( -0.33 V ); the reaction will not occur
B. ( -0.33 V ; ) the reaction will occur
c. ( -2.69 V ); the reaction will not occur
D. ( -2.69 V ); the reaction will occur
12
645 Suppose the concentration of hydroxide ion in the cell is doubled, then the cell
voltage will be:
A. Reduced by half
B. Increased by a factor of 2
c. Increased by a factor of 4
D. Unchanged
12
646 The EMF of the cell
( Z nleft|Z n^{2+}(0.01 M) | F e^{2+}(0.001 M)right| F e ) at
( 298 K ) is 0.2905 then the value of
equilibrium constant for the cell reaction
is :
B. ( 10^{frac{1.33}{35}} )
( mathbf{c} cdot 10 frac{0.25}{15} )
D. ( 10^{frac{0.32}{0.539}} )
12
647 Which of the following reactions is used
to make a fuel cell?
( mathbf{A} cdot 2 H_{2}(g)+O_{2}(g) rightarrow 2 H_{2} O(l) )
B. ( 2 F e(s)+O_{2}(g)+4 H^{+}(a q) rightarrow 2 F e^{2+}(a q)+2 H_{2} O(l) )
( mathbf{c} cdot P b(s)+P b O_{2}(s)+2 H_{2} S O_{4}(a q) rightarrow 2 P b S O_{4}(s)+ )
( H_{2} O(l) )
D. ( C d(s)+2 N i(O H)_{3}(s) rightarrow C d O(s)+2 N i(O H)_{2}+ )
( 2 H_{2} O(l) )
12
648 Cells are connected in series in order to:
A. increase the voltage rating
B. increase the electric current rating.
c. increase the life of cells.
D. none of above.
12
649 Which of the following statements is
correct about ( lambda_{a}^{infty} ) or ( lambda_{c}^{infty} ) (i.e., ionic conductivities)?
A. Increases with temperature due to increase in viscosity of medium.
B. Increases with pressure due to decrease in viscosity of medium.
c. Decreases with pressure due to increase in viscosity of medium.
D. Decreases with pressure due to decrease in viscosity of medium
12
650 Select the correct statements about
SHE:
This question has multiple correct options
( mathbf{A} cdot ) The ( E_{O P}^{o} / R_{R P}^{o} ) for SHE has been arbitrarily assigned to be zero at all temperatures.
B. SHE refers for ( P t, H_{2}(g) mid H^{+}(a q) )
C. SHE is very susceptible to electrode poisoning.
D. SHE is very susceptible to dissolved oxygen, ( mathrm{H}_{2} mathrm{S} ) and all other reducing species.
12
651 The compounds which decompose on
passage of an electric current through them are known as:
A. electrolytes
B. non-electrolytes
c. electrolytically compounds
D. non-electrolytically compounds
12
652 Zinc is used to protect iron from
corrosion because:
( mathbf{A} cdot E_{r e d} ) of ( Z n<E_{r e d} ) of iron
B. ( E_{text {oxidation}} ) of ( Z n<E_{text {oxidation}} ) of iron
C . ( E_{text {oxidation}} ) of ( Z n=E_{text {oxidation}} ) of iron
D. zinc is cheaper than iron
12
653 A cell ( boldsymbol{C u}left|boldsymbol{C u}^{2+} | boldsymbol{A} boldsymbol{g}^{oplus}right| boldsymbol{A} boldsymbol{g} ) initially
contains ( 2 mathrm{M} A g^{oplus} ) and ( 2 mathrm{M} C u^{2+} ) ions in
1 L solution each. The change in cell
potential after it has supplied 1 1 current for 96500 s is :
( mathbf{A} cdot-0.003 V )
в. ( -0.02 V )
c. ( -0.04 V )
D. None of these
12
654 Q. 40 Unlike dry cell, the mercury cell has a constant celu
its useful life. Why?
cury cell has a constant cell potential throughout
o not involved in the overall
12
655 For a number of years, it was not clear whether mercury (I) ion existed in solution as ( H g^{oplus} ) or as ( H g_{2}^{2+} . ) To distinguish between these two possibilities, the following set up was
made:

Hg(I) I Solution A II Solution B I Hg(I) where solution A contained 0.263 g mercury
(I) nitrate per liter and solution B contained 2.63 g mercury
(I) nitrate per litre. If the measured EMF of such a
cell is ( 0.0289 mathrm{V} ) at ( 18^{circ} mathrm{C} ), then mercury
(I) ions exist in the form of ( boldsymbol{H} boldsymbol{g}_{2}^{2+} )
f true enter 1 , else enter 0

12
656 Determine the equilibrium constant of the following reaction at ( 298 K: ) ( 2 F e^{3+}+S n^{2+} rightarrow 2 F e^{2+}+S n^{4+} )
(Given: ( boldsymbol{E}_{boldsymbol{S n}^{4+} / boldsymbol{S n}^{2+}}^{circ}= )
( mathbf{0 . 1 5} )volt; ( boldsymbol{E}_{boldsymbol{F} e^{3+} / mathbf{F e}^{2+}}^{circ}=mathbf{0 . 7 7 1} mathbf{v o l t} mathbf{t} )
12
657 Which one of the following processes
involve chemical reactions?
A. Storing of oxygen gas under pressure in a gas cylinder
B. Liquefaction of air
C. Keeping petrol in a china dish openly
D. Heating copper wire in presence of air at high temperature
12
658 Conductance of ( boldsymbol{A l}^{+mathbf{3}} ) is ( boldsymbol{x} boldsymbol{S} boldsymbol{m}^{2} boldsymbol{g} boldsymbol{e q}^{-1} )
and that of ( S O_{4}^{-2} ) is ( y S m^{2} g e q^{-1} . ) Molar conductance of Aliminium sulphate is ( boldsymbol{S m}^{2} boldsymbol{m} boldsymbol{o l} boldsymbol{e}^{-1} )
A. ( frac{x+y}{6} )
B. ( x+y )
c. ( 6(x+y) )
D. ( 2 x+3 y )
12
659 Glucose saline is used as:
A. salt drink
B. health drink
c. soft drink
D. re-hydrating solution
12
660 Column 1
A) ( wedge^{0}_{m}left(N a N O_{3}right) )
(P) Can be
obtained by Kohlraush law
B) ( wedge^{0}_{m} )
(Q) Can be
obtained by
( left(boldsymbol{C}_{2} boldsymbol{H}_{5} boldsymbol{C O O H}right) quad ) extrapolating
( wedge^{0} m ) vs
( (text {Molarity})^{1 / 2} )
graph to zero molarity.
C) Ilonic conductance
(R) Contribution
by the ion to ( wedge^{0}_{m} )
D) ( wedge^{0}_{m} ) of ( C H_{3} C O O H )
(S) increases on
dilution
A. A-P,R: B-Q,S:C-S:D-S
B. A-P,Q: B-P,S:C-S:D-P,S
c. A-R: B-Q:C-R,S:D-P,Q
D a c. B-Q.R:C-P:D-Q
12
661 Name the substance dissolved in pure
water to make it a conductor of
electricity.
12
662 To prevent a piece of iron from rusting which one of the following metals will provide the best coating?
A. zinc
B. copper
c. Aluminium
D. Leadd
12
663 Calculate the volume of gas liberated at the anode at STP during the electrolysis
of a ( C u S O_{4} ) solution by a current of ( 1 A )
passed for 16 minutes and 5 seconds.
A . ( 224 mathrm{mL} )
в. ( 56 mathrm{mL} )
( c cdot 112 m L )
D. ( 448 mathrm{mL} )
12
664 Consider the cell:
( boldsymbol{C d}(boldsymbol{s})left|boldsymbol{C} boldsymbol{d}^{2+}(mathbf{1} . boldsymbol{0} boldsymbol{M}) | boldsymbol{C} boldsymbol{u}^{2+}(mathbf{0 . 1} boldsymbol{M})right| boldsymbol{C} )
If we wish to make a cell with a more
positive voltage using the same substance, we should:

This question has multiple correct options
A ( cdot ) increase both ( left[C d^{2+}right] ) and ( left[C u^{2+}right] ) to 2.0 M
B. decrease the ( left[C d^{2+}right] ) to ( 0.1 mathrm{M} )
c. increase the ( left[C u^{2+}right] ) to ( 1.0 mathrm{M} )
D. decrease both the ( left[C d^{2+}right] ) and ( left[C u^{2+}right] ) to 0.01 M

12
665 Write the cathodic and anodic cell
reactions of a Hydrogen-Oxygen fuel
cell.
12
666 The electrolyte in lead storage battery is dilute sulphuric acid. The concentration of sulphuric acid in a lead-storage battery must be between ( 4.8 mathrm{M} ) and 5.3 M for most efficient functioning: A 5 mL sulphuric acid sample of a particular battery requires ( 50 mathrm{mL} ) of ( 1.0 mathrm{M} ) NaOH for complete neutralization. Which of the following statements about the functioning of battery is the, most appropriate?
A. The acid concentration in the battery is not in the mos effective range
B. The acid concentration in the battery is in the most effective range
c. The add concentration in the battery is hardly in the most effective range
D. only a good mechanic can tell whether or not the acid concentration in the battery is in the most effective range
12
667 Calculate ( boldsymbol{E}_{text {cell}} )
( boldsymbol{P t}(boldsymbol{s})left|boldsymbol{H}_{2}(boldsymbol{g})_{1 a t m}right| boldsymbol{H} boldsymbol{A}_{left(boldsymbol{K}_{a}=10^{-7}right)} mathbf{1} boldsymbol{M} | boldsymbol{H} boldsymbol{B}_{(boldsymbol{k}} )
A .0 .06
B. 0.03 V
c. ( 0.04 v )
D. ( 0.05 mathrm{v} )
12
668 For car battery which one is correct
statement?
A. Cathode is lead dioxide ( left(P b O_{2}right) ) and anode is copper ( (C u) )
B. Cathode is copper ( (C u) ) and anode is lead dioxide ( left(P b O_{2}right) )
C. Cathode is copper ( (C u) ) and anode is lead ( (P b) )
D. cathode is lead dioxide ( left(P b O_{2}right) ) and anode is lead ( (P b) )
12
669 Q Type your question-
Given ( : boldsymbol{E}_{boldsymbol{L i} oplus mid boldsymbol{L} i}^{ominus}=-mathbf{3 . 0 5} boldsymbol{V} )
[
begin{array}{l}
boldsymbol{E}_{N a oplus mid N a}^{ominus}=-2.71 V \
boldsymbol{E}_{boldsymbol{K}^{oplus} mid boldsymbol{K}}^{ominus}=-mathbf{2 . 9 3} boldsymbol{V}
end{array}
]
Alkali metals react with water
according to the following reaction ( (mathrm{M}= ) Alkali metals):
[
mathbf{2} boldsymbol{M}+boldsymbol{H}_{2} boldsymbol{O} rightarrow mathbf{2} boldsymbol{M} boldsymbol{O} boldsymbol{H}+boldsymbol{H}_{2}
]
It is found that Li reacts gently with
water, whereas K reacts violenly with
water.
Statements
( Delta G ) values have nothing to do with kinetics of the reaction.
The metal having large standard oxidation potential will have lesseer reactivity

Potassium (K) has low melting point and heat of reaction which is sufficient to make it melt or even vapourize. This leads to expotential increase in its surface area.
The ionization potential of ( K ) is
d. smaller than that of Li.

12
670 In the atmosphere of industrial smog, copper corrodes to form:
A. basic copper carbonate and sulphate
B. copper oxide
c. copper sulphide
D. copper nitrate
12
671 Consider the following cell reaction:
[
begin{array}{c}
2 F e(s)+O_{2}(g)+4 H^{+}(a q) rightarrow \
2 F e^{2+}(a q)+2 H_{2} O(l) ; E^{o}=1.67 V
end{array}
]
( mathbf{A t}left[boldsymbol{F} boldsymbol{e}^{2+}right]=mathbf{1 0}^{-mathbf{3}} boldsymbol{M}, boldsymbol{P}_{O_{2}}=mathbf{0 . 1} ) atm
and ( p H=3, ) the cell potential at ( 25^{circ} C )
is:
A . 1.47
B. 1.77 V
c. ( 1.87 mathrm{v} )
D. 1.57 V
12
672 Calomel electrode is reversible with
respect to:
( A cdot H^{+} ) ions
B. ( mathrm{Hg}_{2}^{2+} ) ions
c. ( mathrm{cl}^{-} ) ions
D. None of these
12
673 Which one of the following could not be liberated from a suitable electrolyte by the passage of 0.25 faraday of electricity through that electrolyte
A. 0.25 mole of ( mathrm{Ag} )
B. ( 16 g ) m of ( mathrm{Cu} )
( c cdot 2 g m ) of ( 0_{2}(g) )
D. 2.8ltrs of H at stp
12
674 ( boldsymbol{Z} boldsymbol{n}(boldsymbol{s})left|boldsymbol{Z} boldsymbol{n} boldsymbol{C l}_{2}(boldsymbol{a} boldsymbol{q}) | boldsymbol{C l}^{-}(boldsymbol{a} boldsymbol{q})right| boldsymbol{C l}_{2}(boldsymbol{g}) mid boldsymbol{C} )
In the electrochemical cell described by the cell diagram above, what reaction occurs at the anode?
A. ( Z n rightarrow Z n^{2+}+2 e )
B. ( Z n^{2+}+2 e rightarrow Z n )
c. ( C l_{2}+2 e rightarrow 2 C l )
D. ( 2 C^{-} rightarrow C l_{2}+2 e )
E ( . Z n+C l_{2} rightarrow Z n C l_{2} )
12
675 The conductivity of a saturated solution of ( B a S O_{4} ) is ( 3.06 times 10^{-6} ) ohm ( ^{-1} c m^{-1} )
and its molar conductance is ( 1.53 o h m^{-1} c m^{-1} m o l^{-1} ) the ( K_{s p} ) of
( B a S O_{4} ) will be ?
A ( cdot 4 times 10^{-12} )
В. ( 2.5 times 10^{-9} )
c. ( 2.5 times 10^{-13} )
D. ( 4 times 10^{-6} )
12
676 When a conductance cell was filled with
( 0.0025 mathrm{M} ) solution of ( mathrm{K}_{2} mathrm{SO}_{4} ), its
resistance was 326 ohm. Length of cell
( =100 mathrm{cm} ) and cross-sectional area ( 2.14 times )
( 10^{-4} mathrm{cm}^{2} . ) The specific resistance of ( mathrm{K}_{2} mathrm{SO}_{4} )
is:
( mathbf{A} cdot 4.994 times 10^{-4} )
B . ( 5.997 times 10^{-4} )
( mathbf{c} cdot 6.997 times 10^{-4} )
D. ( 7.997 times 10^{-4} )
12
677 Who invented the first true battery?
A. Faraday
B. onm
c. volta
D. Alva Edison
12
678 If the ( Delta G ) of a cell reaction, ( A g C l+ )
( e^{-} rightarrow A g+C l^{-} ) is ( -21.20 mathrm{kJ}, ) the
standard emf of cell is
A . ( 0.239 mathrm{v} )
B. ( 0.220 v )
c. ( -0.320 v )
D. – 0.110v
12
679 The dissociation constant on n-butyric
acid is ( 1.6 times 10^{-5} ) and the molar
conductivity at infinite dilution is
( 380 times 10^{-4} S m^{2} m o l^{-1} . ) The specific
conductance of the ( 0.01 mathrm{M} ) acid solution
is:
A ( cdot 1.52 times 10^{-5} mathrm{Sm}^{-1} )
В. ( 1.52 times 10^{-2} mathrm{Sm}^{-1} )
C. ( 1.52 times 10^{-3} mathrm{Sm}^{-1} )
D. None
12
680 A current is passed through 500 mLof
an aqueous solution of ( boldsymbol{C a} boldsymbol{I}_{2} ). After
sometime, it is observed that 50
millimoles of ( I_{2} ) have been formed.
Which of the following statements is(are) correct?
This question has multiple correct options
A. The number of faradays of charge passed through the solution is ( 0.10 F )
B. The volume of dry ( H_{2} ) at ( S T P ) that has been formed during electrolysis is ( 1120 mathrm{mL} ).
c. The ( p H ) of the solution is nearly 0.7
D. The mass of calcium produced is ( 2.0 g ).
12
681 The electric charge for electrode deposition of 1 g equivalent of a substance is:
A. 1 ampere per second
B. 96500 Coulombs per second
c. 1 ampere for one hour
D. The charge on one mole of electrons
12
682 lumn I with the units given in Column II.
Column 11
. 50 Match the terms given in Column I with the units
Column!
1. Sem
2 mt
CK
3. Sem? mol
D G
4 V
12
683 An electric current is passed through
silver voltameter connected to a water
voltameter. The cathode of the silver
voltameter weighed ( 0.108 g ) more at the end of the electrolysis. The volume of oxygen evolved at STP is:
( mathbf{A} cdot 56 mathrm{cm}^{3} )
В. ( 550 mathrm{cm}^{3} )
( c cdot 5.6 mathrm{cm}^{3} )
D. ( 11.2 mathrm{cm}^{3} )
E . ( 22.4 mathrm{cm}^{3} )
12
684 Molar conductivities of oxalate, ( boldsymbol{K}^{+} ) and
( N a^{+} ) ions at infinite dilution are 148.2 ( mathbf{5 0 . 1 , 7 3 . 5} S mathrm{cm}^{2} ) mol ( ^{-1} ) respectively.
Then, equivalent conductivity at infinite dilution for sodium-potassium oxalate ( left[left(boldsymbol{C O O}^{-}right)_{2} boldsymbol{N} boldsymbol{a}^{+} boldsymbol{K}^{+}right] ) will be:
A. ( 271.8 mathrm{S} mathrm{cm}^{2} ) eq ( ^{-1} )
В. ( 67.95 mathrm{S} mathrm{cm}^{2} mathrm{eq}^{-1} )
c. ( 543.6 S mathrm{cm}^{2} e q^{-1} )
D. ( 135.9 S mathrm{cm}^{2} e q^{-1} )
12
685 toppr )
Q Type your question_
watches, etc.
(ii) It consists of zinc-mercury
amalgam as anode and a paste of HgO
and carbon as the cathode.
(iii) The electrolyte is a paste of
( Z n(O H)_{2} ) and ( K O_{2} )
(iv) The electrode reactions for the cell
are
At anode: ( Z n(H g)+H_{2} O rightarrow Z n O_{(s)}+ )
( 2 O H^{-}+2 e^{-} )
At cathode: ( boldsymbol{H} boldsymbol{g} boldsymbol{O}+boldsymbol{H}_{2} boldsymbol{O}+boldsymbol{2} boldsymbol{e}^{-} rightarrow )
( boldsymbol{H} boldsymbol{g}_{(l)}+2 boldsymbol{O} boldsymbol{H} )
A. (ii) and (iii) only
B. (i) ad (ii) only
C. (i), (iii) and (iv) only
D. (iii) and (iv) only
12
686 ( 100 mathrm{ml} mathrm{CuSO}_{4} ) (aq) was electrolyzed using inert electrodes by passing 0.965 A till the ( p H ) of the resulting solution was ( 1 . ) The solution after electrolysis was
neutralized, treated with excess ( K I )
and titrated with ( 0.04 mathrm{M} N a_{2} S_{2} O_{3} )
Volume of ( N a_{2} S_{2} O_{3} ) required was 35
ml. Assume no volume change
during electrolysis. If the initial
concentration ( (mathrm{M}) ) of ( mathrm{CuSO}_{4} ) was ( 64 times )
( 10^{-x}, ) then what is the value of ( x ? )
12
687 The resistance of a conductivity cell
containing ( 0.001 mathrm{M} ) KCl solution at ( 298 mathrm{K} ) is ( 1500 Omega . ) What is the cell constant if
conductivity of ( 0.001 mathrm{M} ) KCl solution at ( 298 K ) is 0.146 times ( 10^{-3} S c m^{-1} ? )
12
688 Q1. What is meant by electrochemical series? What are characteristics of electrochemical series? 12
689 An electrochemical cell is constructed
with an open swtich as shown below:
When the switch is closed, mass of tin-
electrode increases. If ( boldsymbol{E}^{circ}left(boldsymbol{S} boldsymbol{n}^{2+} / boldsymbol{S} boldsymbol{n}right)= )
( -0.14 V ) and for ( E^{circ}left(X^{n+} / Xright)= )
( -0.78 V ) and initial emf of the cell is
( 0.65 mathrm{V}, ) determine ( n )
( A cdot 3 )
в.
( c .5 )
( D )
12
690 State True or False.
Pure water can be used as an electrolyte in the process of electrolysis.
A. True
B. False
12
691 If copper is kept open in air, it slowly loses its shining brown surface and gains a green coating. It is due to the formation of:
A ( cdot C u C O_{3} )
в. ( C u S O_{4} )
c. ( C u C O_{3} cdot C u(O H)_{2} )
D. ( C u O )
12
692 Which of the following will increase the voltage of the cell?
( boldsymbol{S} boldsymbol{n}(boldsymbol{s})+boldsymbol{2} mathbf{A} mathbf{g}^{+}(boldsymbol{a} boldsymbol{q}) rightarrow boldsymbol{2} boldsymbol{A} boldsymbol{g}(boldsymbol{s})+boldsymbol{S} boldsymbol{n}^{2+} )
A. Increase in the concentration of ( operatorname{Sn}^{2+} ) ions
B. Increase in the concentration of ( A g^{+} ) ions
c. Increase in the size of silver rod
D. Removal of salt bridge
12
693 The tarnishing of silver ornaments in
atmosphere is due to:
This question has multiple correct options
A. ( A g_{2} O )
в. ( A g_{2} S )
c. ( A g_{2} C O_{3} )
D. ( A g_{2} S O_{4} )
12
694 Question 10. The conductivity of sodium chloride at 298 K has been
determined at different concentrations and the results are given below:
Concentration/M 0.001 0.010 0.0200.050 0.100
10-2 x k/Sm-? 1.237 11.85 23.15 55.53 106.74
12
Calculate 4 for all concentrations and draw a plot between Am. and C .
Find the value of me
In order to plot a graph between Am and JC first find the values of C2
and am and plot the graph. After that find am from the graph, as it is
equal to the intercept on the maxis.
12
695 Give reasons:
On the basis of ( E^{circ} ) values, ( O_{2} ) gas
should be liberated at anode but it is
( C l_{2} ) gas which is liberated in the
electrolysis of aqueous NaCl.
12
696 The electrolytic process by which an oxide of metal is coated over metal
surface is called:
A. electrolysis
B. electroplating
c. anodising
D. electrorefining
12
697 Assertion
In an electrochemical cell, the electrode
that is the site of reduction is called the
anode.
Reason
Oxidation always occurs at the cathode.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
698 A silver article generally turns black when kept in the open for a few days. The article when rubbed with
toothpaste again starts shining. Name the black substance formed and give its chemical formula:
A . silver oxide, ( left(A g_{2} text { , } ) ) right.
B. Silver chloride, ( (A g C l) )
C. Silver sulphide, ( left(A g_{2} Sright) )
D. silver iodide,( ( (A g I) )
12
699 What is the standard reduction
potential ( left(boldsymbol{E}^{o}right) ) for ( boldsymbol{F} boldsymbol{e}^{mathbf{3}+} rightarrow boldsymbol{F} boldsymbol{e} )
Given that:
( boldsymbol{F} boldsymbol{e}^{2+}+boldsymbol{2} boldsymbol{e} boldsymbol{6}-rightarrow boldsymbol{F} boldsymbol{e} ; boldsymbol{E}_{boldsymbol{F}}^{o} boldsymbol{e}_{boldsymbol{F} e^{2+} / boldsymbol{F} e}= )
( -0.47 V )
( boldsymbol{F} boldsymbol{e}^{boldsymbol{3}+}+boldsymbol{e}^{-} rightarrow boldsymbol{F} boldsymbol{e}^{2+} ; boldsymbol{E}_{boldsymbol{F} e^{3+} / boldsymbol{F} e^{2+}}^{o}= )
( +0.77 V )
A ( .+0.057 V )
в. ( +0.30 V )
c. ( -0.30 V )
D. ( -0.057 V )
12
700 Match the List I with the List II. 12
701 The standard electrode potential ( left(E^{circ}right) )
for Daniel cell is ( +1.1 mathrm{V} ). Calculate ( Delta G^{circ} )
for the reaction.
( boldsymbol{Z} boldsymbol{n}(boldsymbol{s})+boldsymbol{C} boldsymbol{u}_{(a q)}^{2+} rightarrow boldsymbol{Z} boldsymbol{n}_{(a q)}^{2+}+boldsymbol{C u}(boldsymbol{s}) )
( (1 F=96500 C / m o l) )
12
702 The chemical reaction, ( 2 A g C l_{(s)}+ )
( boldsymbol{H}_{2(g)} rightarrow 2 boldsymbol{H} boldsymbol{C l}_{(a q)}+boldsymbol{2} boldsymbol{A} boldsymbol{g}_{(s)} ) taking
place in a galvanic cell is represented by the notation:
A ( cdot P t_{(s)} mid H_{2(g)}, 1 ) bar ( left|1 M K C l_{(a)}right| A g C l_{(s)} mid A g_{(s)} )
B . ( P t_{(s)} mid H_{2(g)}, 1 ) bar ( mid 1 ) M ( H C l_{(a q)}left|1 M A g_{(a q)}^{+}right| A g_{(s)} )
C. ( P t_{(s)} mid H_{2(g)}, 1 ) bar ( mid 1 ) M ( H C l_{left(a_{9}right)}left|A g C l_{(s)}right| A g_{(s)} )
D. ( P t_{s} mid H_{2(g)}, 1 ) bar ( left|1 M H C l_{(a q)}right| A g_{(s)} mid A g C l_{s} )
12
703 Question 11. Conductivity of 0.00241M acetic acid is
7.896 x 10-5 S cm-1
Calculate its molar conductivity. If for acetic acid is 390.5 S cmmol-,
what is its dissociation constant?
Use the formula 1m =
to find molar conductivity;
Ca²
so calculate Ka (dissociation constant) as you know Cand a.
12
704 A magnet is pulled away from a conducting coil in a circuit. The direction of the induced emf in the coil
can be found from…………………
A. Faraday’s law of electromagnetic induction
B. Joule’s law
c. Lenz’s law
D. Fleming’s left hand rule
12
705 Define the terms conductivity and
molar conductivity for the solution of an electrolyte. Comment on their variation
with temperature.
12
706 The EMF of an ( boldsymbol{H}_{2}-boldsymbol{O}_{2} ) fuel cell:
( A cdot ) is independent of partial pressures of ( H_{2} ) and ( O_{2} )
B. decreases on increasing ( P_{H_{2}} ) and ( P_{O_{2}} )
C. increases on increasing ( P_{H_{2}} ) and ( P_{O_{2}} )
D. varies with the concentration of ( O H^{-} ) ions in the
cathodic and anodic compartments
12
707 What happens to molar conductivity
when one mole of ( K C l ) dissolved in one
litre is diluted to five liters?
12
708 Which one of the following statements
is incorrect?
A. Specific conductivity decreases with dilution
B. Equivalent and molar conductivities increases with dilution
( mathrm{C} cdot Lambda_{m}^{o} ) for a weak electrolyte cannot be found by
extrapolation of ( Lambda_{m} ) to zero concentration
D. Molar conductivity of a strong electrolyte increases with dilution because ionization increases with dilution
12
709 How much electricity in terms of Faraday is required to produce 100 g of
Ca from molten ( C a C l_{2} ? )
A . 1 F
в. 2 F
( c .3 ) F
D. 5
12
710 For a cell, the cell reaction is ( M g(s)+ ) ( C u^{2+}(a q) rightarrow M g^{2+}(a q)+C u(s) . ) If the
S.R.P. values of ( M g ) and ( C u ) are ( -2.37 V )
and ( +0.34 V ) respectively, the EMF of the
cell is:
A ( .+2.03 V )
B . ( -2.03 mathrm{V} )
( mathrm{c} ldots+2.71 mathrm{V} )
D. ( -2.71 V )
12
711 Question 4. What does the negative sign in the expression
EZ 2+ /Zn) = -0.76V mean?
12
712 Lead pipes are readily corroded by:
A. water
B. acetic acid
c. conc. ( H_{2} S O_{4} )
D. dil. ( H_{2} S O_{4} )
12
713 A galvanic cell is constructed using the
redox reaction, it is represented as:
( frac{1}{2} H_{2}(g)+A g C l(s) rightleftharpoons H^{+}(a q)+ )
( boldsymbol{C l}^{-}(boldsymbol{a} boldsymbol{q})+boldsymbol{A} boldsymbol{g}(boldsymbol{s}) )
( mathbf{A} cdot P tleft|H_{2}(g)right| H C l(s o l n .) | A g N O_{3}(s o l n .) mid A g )
B ( cdot A g|A g C l(s)| K C l(s o l n .) mid H C l(text {soln.}), H_{2}(g) mid P t )
( mathbf{c} cdot P tleft|H_{2}(g)right| K C l(s o l n .) | A g C l(s) mid A g )
( mathbf{D} cdot P tleft|H_{2}(g), H C l(s o l n .) | A g C l(s)right| A g )
12
714 54
NCERT Exem
lectrolysis of aqueous solution of CuSO4 by
Q. 23 What will happen during the electrolysis of aqueo
using platinum electrodes?
(a) Copper will deposit at cathode (b) Copper will dep
(C) Oxygen will be released at anode (d) Copper will disso
Thinking Process
This problem is based on electrolysis of electrolytes.
(6) Copper will deposit at anode
(d) Copper will dissolve at anode
node
12
715 State the Kohlrausch law of
independent migration of ions. Why
does the conductivity of a solution decrease with dilution?
12
716 2. 29 Can Ecell or 4, Gº for cell reaction ever be equal to zero? 12
717 What is electrolysis? A solution of
( C u S O_{4} ) is electrolysed for 10 minutes
with a current of 1.5 amperes. What is
the mass of copper deposited at the cathode?
12
718 Process of depositing a thin layer of zinc metal on iron objects is called:
A. rusting
B. corrosion
c. sublimation
D. galvanisation
12
719 ( ln ) a fuel cell ( H_{2} ) and ( O_{2} ) react to
produce electricity. In the process ( boldsymbol{H}_{2} )
gas is oxidized at anode and ( O_{2} ) at
cathode. If 67.2 litre of ( H_{2} ) at STP reacts
in 15 minutes. The average current
produced is:
( A cdot 643.33 mathrm{A} )
B. 642.33 А
c. ( 682.33 mathrm{A} )
D. None of the above
12
720 During discharging of lead-storage acid battery following reaction takes place:
( boldsymbol{P b}(s)+boldsymbol{P b O}_{2}(s)+2 boldsymbol{H}_{2} boldsymbol{S} boldsymbol{O}_{4} rightarrow )
( 2 P b S O_{4}(s)+2 H_{2} O )
If 2.5 amp of current is drawn for 965
minutes, ( H_{2} S O_{4} ) consumed is:
A. 0.75 mol
B. 3.00 mol
c. 1.50 mol
D. 4.50 mol
12
721 Fill in the blanks:
Electrolysis is the passage of ( _{text {一一一一一一一 }} ) (electricity / electrons) through a liquid or a solution accompanied by a (physical/ chemical) change.
12
722 When ( X ) amperes of current is passed through molten ( A l C l_{3} ) for 96.5 seconds.
0.09 grams of aluminium is deposited. What is the value of ( X ? )
A . 10
B. 20
( c . ) 30
( D cdot 40 )
12
723 A zinc electrode is placed in a ( 0.1 mathrm{M} )
solution at ( 25^{0} C . ) assuming that the salt is ( 20 % ) dissociated at this dilutions
calculate the electrode reduction
potential. ( boldsymbol{E}^{0}left(boldsymbol{Z} boldsymbol{n}^{2+} mid boldsymbol{Z} boldsymbol{n}right)=-mathbf{0 . 7 6} boldsymbol{V} )
12
724 At ( 25^{circ} C, ) the equivalent conductance at
infinite dilution of ( H C l, C H_{3} C O O N a )
and ( N a C l ) are 426.1,91.0 and
( 126.45 c m^{2} Omega^{-1} e q^{-1} ) respectively, the
( wedge_{infty} ) for ( boldsymbol{C H}_{3} boldsymbol{C O O H}left(boldsymbol{i n} boldsymbol{c m}^{-1} boldsymbol{Omega}^{-1} boldsymbol{e q}^{-1}right) )
is:
( mathbf{A} cdot 391.6 )
B. 390.6
( c .389 .6 )
D. 388.6
12
725 The variation of ( A_{m} ) acetic acid with
concentration is correctly represented
by:
( A )
B.
( mathbf{c} )
D.
12
726 Iron can be prevented from rusting by:
This question has multiple correct options
A. connecting iron to more electropositive metal a case of cathodic protection.
B. connecting iron to more electropositive metal a case of anodic protection.
c. connecting iron to less electropositive metal a case of anodic protection
D. connecting iron to less electropositive metal a case of cathodic protection.
12
727 Question 8. The conductivity of 0.20M solution of KCl at 298K is
0.0248 S cm . Calculate its molar conductivity.
we Molar conductivity is calculated as Ame ‘ mol-‘cm?. So, first
convert concentration (mol/L) into mol cm and then calculate molar
conductivity.
12
728 Assertion: Copper sulphate solution can be stored in a zinc vessel.
Reason: ( boldsymbol{E}_{boldsymbol{C u}^{2+} mid boldsymbol{C u}}^{ominus}= )
( mathbf{0 . 3 4} boldsymbol{V}, boldsymbol{E}_{Z n^{2+} mid mathbf{Z} n}^{ominus}=-mathbf{0 . 7 6} boldsymbol{V} )
( boldsymbol{E}_{A boldsymbol{g}^{oplus} mid A boldsymbol{g}}^{ominus}=mathbf{0 . 8 0} boldsymbol{V} )
A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c. Assertion is true but Reason is false
D. Assertion is false but Reason is true
E. Both Assertion and Reason are false
12
729 Assertion
Ionic compounds are bad conductors of electricity.
Reason
In ionic compounds mobile ions exists.
A. Both Assertion and Reason are correct and Reason is
the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is
not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Assertion is incorrect and the Reason is correct
12
730 Define fuel cell and write its two
advantages.
12
731 Chemical effect of electric current may
cause:
A. formation of gas bubbles at the electrodes
B. deposit of metal on the electrodes
C. change in colour of the solution
D. all of above
12
732 Which of the following quantity is always positive for a spontaneous chemical reaction?
A. Standard voltaic potential
B. Entropy
c. Enthalpy
D. Reaction rate
E. Gibbs free energy
12
733 More electronegative elements have:
A. negative reduction potential
B. tendency to lose electrons
C. positive reduction potential
D. positive oxidation potential
12
734 A battery jar contained a solution of
copper sulfate. Two electrodes. one
made of copper the other a metal object to be copper plated, were placed in the jar and connected to a source of direct current. Which of the following statements concerning this system is correct?
A. The object to be placed is the anode
B. Oxidation occurs at the anode
c. The sulfate ions migrate toward the cathode
D. The concentration of the copper sulfate solution increases as electrolysis proceeds
E. The copper electrode increases in mass
12
735 After electrolysis of a sodium chloride
solution with inert electrodes for a
certain period of time, ( 600 m L ) of the
solution was left which was found to be
( 1 N ) in ( N a O H . ) During the same period
( 31.75 g ) of copper was deposited in the copper voltameter in series with the
electrolytic cell. Calculate the percentage theoretical yield of ( N a O H ) obtained.
12
736 The equilibrium constant for the reaction
is:
( 2 F e^{3+}+3 I^{ominus} rightleftharpoons F e^{3+}+C e^{3+} )
Given :
( E_{C e^{4+1} C e^{3+}}=1.44 mathrm{V} )
( E_{F e^{3+} 1 F e^{2+}}^{ominus}=0.68 mathrm{V} )
A . ( 7.236 times 10^{12} )
B . ( 7.386 times 10^{12} )
c. ( 7.158 times 10^{12} )
D. None of these
12
737 Ihs
Q. 65 Assertion (A) Copper sulphate can be stored in zinc vessel.
Reason (R) Zinc is less reactive than copper.
12
738 Limiting molar conductivity of NaBr is:
( mathbf{A} cdot Lambda_{m}^{o} N a B r=Lambda_{m}^{o} N a C l+Lambda_{m}^{o} K B r )
B. ( Lambda_{m}^{o} N a B r=Lambda_{m}^{o} N a C l+Lambda_{m}^{o} K B r-Lambda_{m}^{o} K C l )
( mathbf{C} cdot Lambda_{m}^{o} N a B r=Lambda_{m}^{o} N a O H+Lambda_{m}^{o} N a B r-Lambda_{m}^{o} N a C l )
( mathbf{D} cdot Lambda_{m}^{o} N a B r=Lambda_{m}^{o} N a C l-Lambda_{m}^{o} N a B r )
12
739 What is the cell reaction occurring in
Daniell cell (galvanic cell)?
( mathbf{A} cdot C u(s)+Z n S O_{4}(a q .) rightarrow C u S O_{4}(a q .)+Z n(s) )
B ( cdot Z n(s)+C u S O_{4}(a q .) rightarrow C u(s)+Z n S O_{4}(a q .) )
( mathbf{c} cdot N i(s)+Z n S O_{4}(a q .) rightarrow N i S O_{4}(a q .)+Z n(s) )
( mathbf{D} cdot 2 N a(s)+C d S O_{4}(a q .) rightarrow N a_{2} S O_{4}(a q .)+C d(s) )
12
740 Assertion: The Nernst equation gives concentration dependence of EMF of the
cell.
Reason: In a Daniell cell current flows
from cathode to anode.
A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c. Assertion is true but Reason is false
D. Assertion is false but Reason is true
E. Both Assertion and Reason are false
12
741 Question 2. Can you store copper sulphate solutions in a zinc pot?
Consider the Eº values of copper and zinc. More the negative value of E
higher is the reactivity and a more reactive metal can displace a less
reactive metal from its salt solution.
12
742 The below reaction is the gold-plating process reaction.
[
boldsymbol{A} boldsymbol{u}^{3+}(boldsymbol{a q})+boldsymbol{3} boldsymbol{e}^{-} rightarrow boldsymbol{A} boldsymbol{u}(boldsymbol{s})
]
If ( 0.600 g ) of ( A u ) is plated onto a metal how many coulombs are used?
( mathbf{A} cdot 299 C )
B. ( 868 C )
( c .2,990 C )
D. ( 8,680 C )
12
743 ( boldsymbol{Z} boldsymbol{n}(boldsymbol{s})left|boldsymbol{Z} boldsymbol{n} boldsymbol{C l}_{2}(boldsymbol{a} boldsymbol{q}) | boldsymbol{C l}^{-}(boldsymbol{a q})right| boldsymbol{C l}_{2}(boldsymbol{g}) mid boldsymbol{C} )
In the electrochemical cell described by
the cell diagram above, what reaction occurs at the anode?
A. ( Z n rightarrow Z n^{2+}+2 e^{-} )
B. ( Z n^{2+}+2 e^{-} rightarrow Z n )
c. ( C l_{2}+2 e^{-} rightarrow 2 C l )
D. ( 2 C l^{-} rightarrow C l_{2}+2 e^{-} )
12
744 A conductance cell was filled with 0.01
molar KCl. Its resistance was found to
be 150 ohm at ( 25^{circ} mathrm{C} ). The conductivity
was observed to be ( 0.00177 S c m^{-1} . ) The
cell was when washed and filled with
0.05 molar solution of NaCl whose
resistance was found to be 325 ohm.
Conductivity of NaCl solution is:
B. ( 9.168 times 10^{-4} mathrm{Scm}^{-1} )
c. ( 8.169 times 10^{-4} mathrm{Scm}^{-1} )
D. None of these
12
745 The extent of charge of lead
accumulator is determined by:
( mathbf{A} cdot ) amount of ( P b S O_{4} ) in the battery
B. amount of ( P b O_{2} ) in the battery
C . specific gravity of ( H_{2} S O_{4} ) of the battery
D. amount of ( P b ) in the battery
12
746 Assertion
If two half reaction with electrode
potential ( E_{1}^{o} ) and ( E_{2}^{o} ) gives a third half
reaction, then ( Delta G_{3}^{o}=Delta G_{1}^{o}+Delta G_{2}^{o} )
Reason
( boldsymbol{E}_{mathbf{3}}^{boldsymbol{o}}=boldsymbol{E}_{mathbf{1}}^{boldsymbol{o}}+boldsymbol{E}_{mathbf{2}}^{boldsymbol{o}} )
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
747 Answer the following.
a. What is done to prevent corrosion of
metals?
b. What are the metals that make the
alloys brass and bronze?
12
748 The molar conductance (in
( left.mathbf{Omega}^{-1} boldsymbol{c m}^{2} boldsymbol{m o l}^{-1}right) ) of ( boldsymbol{K}_{2} boldsymbol{S} boldsymbol{O}_{4} ) solution is:
12
749 Electrolyte for silver plating is:
A. potassium nitrate solution
B. dilute sulphuric acid
C. double cyanide of silver and potassium solution
D. any of the above
12
750 For the reaction:
( boldsymbol{F} boldsymbol{e}^{2+}(boldsymbol{a} boldsymbol{q})+boldsymbol{A} boldsymbol{g}^{+}(boldsymbol{a} boldsymbol{q}) longrightarrow boldsymbol{A} boldsymbol{g}(boldsymbol{s})+ )
( boldsymbol{F} boldsymbol{e}^{+boldsymbol{3}}(boldsymbol{a} boldsymbol{q}) )
Predict which change will decrease the cell voltage?
A. Increase the amount of Agg
B. Decrease the concentration of ( A g^{+} )
C. Increase the concentration of ( F e^{+3} )
D. Both ( B ) and ( C )
12
751 ( E_{1}, E_{2}, E_{3} ) are the emf values of the
three galvanic cells respectively.
(i) ( Z nleft|Z n_{1 M}^{2+}right|left|C u_{0.1 M}^{2+}right| C u )
( (text { ii }) Z nleft|Z n_{1 M}^{2+}right|left|C u_{1 M}^{2+}right| C u )
(iii) ( Z nleft|Z n_{0.1 M}^{2+} | C u_{1 M}^{2+}right| C u )
Which one of the following is true?
A ( . E_{2}>E_{3}>E_{1} )
в. ( E_{3}>E_{2}>E_{1} )
c. ( E_{1}>E_{2}>E_{3} )
D. ( E_{1}>E_{3}>E_{2} )
12
752 What is electroplating? Explain the process. Give two uses of electroplating 12
753 Which of the following statement is not
true?
A. metals produce a ringing sound when struck hard
B. copper doesn’t get rusted
C. coal and sulphur are soft and dull in appearance
D. magnesium and phosphorous burn vigorously in air
12
754 The standard electrode potential ( left(boldsymbol{E}^{ominus}right) ) for ( boldsymbol{O C l}^{-} mid boldsymbol{C l}^{-} ) and ( boldsymbol{C l}^{-} mid frac{mathbf{1}}{mathbf{2}} boldsymbol{C l}_{2} )
respectively are ( 0.94 mathrm{V} ) and ( -1.36 mathrm{V} ). The
( boldsymbol{E}^{ominus} ) value of ( boldsymbol{O} boldsymbol{C l}^{-} mid frac{boldsymbol{1}}{boldsymbol{2}} boldsymbol{C l}_{2} ) will be:
A. ( -0.42 mathrm{v} )
в. ( -2.20 mathrm{v} )
c. ( 0.52 mathrm{v} )
D . 1.04
12
755 If ( m ) is the mass of silver deposited at
the cathode by ( 2 A ) current flowing for
( 25 m i n ) through a silver voltameter, then
the mass deposited by ( 1.5 A ) current flowing for ( 600 s ) is
A .
в. ( 3 m )
( mathrm{c} .0 .3 mathrm{m} )
D. None
12
756 The equilibrium constant for the redox change
( left[2 A gleft(N H_{3}right)_{2}^{+}+C_{6} H_{12} O_{6}+H_{2} O rightarrowright. )
( boldsymbol{C}_{6} boldsymbol{H}_{12} boldsymbol{O}_{7}+boldsymbol{2} boldsymbol{A} boldsymbol{g}(boldsymbol{s})+boldsymbol{C}_{6} boldsymbol{H}_{12} boldsymbol{O}_{2}+ )
( left.mathbf{2} boldsymbol{H}^{+}right] ) is:
( mathbf{A} cdot 5.15 times 10^{9} )
В. ( 4,2 times 10^{5} )
c. ( 1.72 times 10^{-11} )
12
757 The same quantity of electricity is passed through ( A l_{2}left(S O_{4}right)_{3} ) and ( A g N O_{3} ) solution with platinum electrodes. If ( n ) number of Al atoms are deposited on the cathode, the number of Ag atoms deposited on the cathode will be:
( A )
B. 2n
( c cdot 3 n )
D. n/2
12
758 ( Z n ) Amalgam is prepared by the
electrolysis of aqueous ( Z n C l_{2} ) using ( H g ) cathode ( (9 mathrm{gm}) . ) How much current
should be passed through ( Z n C l_{2} ) solution for 1000 seconds to prepare a
( Z n ) amalgam with ( 25 % Z n ) by weight ? ( (Z n text { atomic weight }=65.4) )
A . ( 5.6 mathrm{A} )
в. 7.2 A
( c cdot 8.85 A )
D. 11.2 A
12
759 Anodic oxidation of ammonium
hydrogen sulphate produces ammonium persulphate. ( N H_{4} H S O_{4} rightarrow N H_{4} S O_{4}^{-}+H^{+} )
( mathbf{2} boldsymbol{N} boldsymbol{H}_{4} boldsymbol{S} boldsymbol{O}_{4}^{-} rightarrowleft(boldsymbol{N} boldsymbol{H}_{4}right)_{2} boldsymbol{S}_{2} boldsymbol{O}_{8}+boldsymbol{2} boldsymbol{e}^{-} )
(Anodic oxidation)
( 2 H^{+}+2 e^{-} rightarrow H_{2} ) (Cathodic reduction)
Hydrolysis of ammonium persulphate
forms ( boldsymbol{H}_{2} boldsymbol{O}_{2} )
( left(N H_{4}right)_{2} S_{2} O_{8}+2 H_{2} O rightarrow )
( mathbf{2} boldsymbol{N} boldsymbol{H}_{mathbf{4}} boldsymbol{H} boldsymbol{S} boldsymbol{O}_{4}+boldsymbol{H}_{2} boldsymbol{O}_{2} )
Current efficiency inn electrolytic process is ( 60 % ). Calculate the amount of
current required to produce ( 85 g ) of
( boldsymbol{H}_{2} boldsymbol{O}_{2} ) per hour
Hydrolysis reaction shows ( 100 % ) yield.
12
760 The ( E_{c e l l}^{o} ) for ( C uleft|C u^{2+}right|left|A g^{+}right| A g ) in volt is
A. +0.449
B. +0.474
c. -0.449
D. -0.474
12
761 The ( E_{text {cell }}^{o} ) for ( boldsymbol{C u}left|boldsymbol{C} boldsymbol{u}^{2+} | boldsymbol{A} boldsymbol{g}^{+}right| boldsymbol{A} boldsymbol{g} ) is:
A . ( 0.415 V )
в. ( 0.374 V )
c. ( -0.415 V )
D. ( -0.374 V )
12
762 For the given cell reaction: ( boldsymbol{F e}^{2+}+ ) ( boldsymbol{C} boldsymbol{e}^{4+} rightleftharpoons boldsymbol{F} boldsymbol{e}^{boldsymbol{3}+}+boldsymbol{C} boldsymbol{e}^{boldsymbol{3}+} . ) The equilibrium
constant is:
(Given: ( boldsymbol{E}_{C e^{4+} / C e^{3+}}^{circ}= )
( left.mathbf{1 . 4 4} boldsymbol{V} ; boldsymbol{E}_{boldsymbol{F} e^{2+} / boldsymbol{F} e^{3+}}^{circ}=mathbf{0 . 6 8} boldsymbol{V}right) )
12
763 The resistance of a ( frac{N}{10} K C l ) aqueous solution is ( 245 Omega ). If the electrodes in the
cell are ( 4 mathrm{cm} ) apart and area having
( 77 mathrm{cm}^{2} ) each, the molar conductance of
the solution will be:
A . 233
B. 2.12
c. 23.32
D. 0.233
12
764 The thermodynamic efficiency of cell is given by:
A. ( Delta H / Delta G )
в. ( frac{n F E}{Delta G} )
c. ( frac{-n F E}{Delta H} )
D ( cdot n F E^{ominus} )
12
765 Assertion: The density of ( boldsymbol{H}_{2} boldsymbol{S} boldsymbol{O}_{4} )
decreases in lead storage cell during discharging. Reason: Calomel electrode is
a reference electrode and it is better
than hydrogen electrode.
A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c. Assertion is true but Reason is false
D. Assertion is false but Reason is true
E. Both Assertion and Reason are false
12
766 The equilibrium constant for the following reaction is:
( 2 F e^{3+} 3 I^{ominus} rightleftharpoons 2 F e^{2+}+I_{3}^{ominus} )
The standard reduction potential in
acidic conditions is ( 0.78 V ) and ( 0.54 V )
respectively, for ( boldsymbol{F e}^{mathbf{3}}+ )
( left|boldsymbol{F} boldsymbol{e}^{2+} boldsymbol{a} boldsymbol{n} boldsymbol{d} boldsymbol{I}_{3}^{ominus}right| boldsymbol{I}^{ominus} ) couples
( mathbf{A} cdot K_{e q}=10^{8} )
В. ( K_{e q}=10^{7} )
( mathbf{c} cdot K_{e q}=10^{5} )
D. None of these
12
767 In rusting of iron, iron is oxidised and ( mathrm{O}_{2} )
is reduced. The no. of electrons used
during reduction ( mathrm{O}_{2} ) are :
12
768 What are galvanic cells? Explain the construction and working of galvanic cell with an example? 12
769 Assertion
Iron is protected from corrosion by connecting magnesium metal with it.
Reason

Iron acts as cathode and magnesium as anode which gradually disappears.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect

12
770 Assertion
If standard reduction potential for the
reaction ( boldsymbol{A} boldsymbol{g}^{+}+boldsymbol{e}^{-} rightarrow boldsymbol{A} boldsymbol{g} ) is 0.80 volt,
then for the reaction ( 2 A g^{+}+2 e^{-} rightarrow )
2 Ag.lt will be 1.60 volt.
Reason
If concentration of ( A g^{+} ) ions is doubled
the standard electrode potential is also doubled.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
771 If the molar concentration of ( boldsymbol{P b I}_{2} ) is
( 1.5 times 10^{-3} ) mol ( L^{-1}, ) then the
concentration of iodide ions in ( g ) ion ( L^{-1} )
is:
A. ( 3.0 times 10^{-3} )
В. ( 6.0 times 10^{-3} )
D. ( 0.6 times 10^{-6} )
12
772 Conductivity (Unit Siemen’s ‘S’) is
directly proportional to area of the
vessel and the concentration of the
solution in it and is inversely proportional to the length of the vessel,
then the unit of constant of
proportionality is
( mathbf{A} cdot S m m o l^{-1} )
B. ( S m^{2} m o l^{-1} )
c. ( S^{-2} m^{2} ) mol
D. ( S^{2} m^{2} ) mol ( ^{-2} )
12
773 ( mathbf{Lambda}_{infty} ) of propionic acid cannot be
determined experimentally because:
A. conductance at high concentration cannot be determined
B. conductance at low concentration cannot be determined
c. conductance a thigh pressure cannot be determined
D. all of the above
12
774 How many molecules of ( C O_{2} ) are formed
when one molecule of ( C_{6} H_{12} O_{6} ) is
oxidised in our body?
A . 4
B. 2
( c cdot 6 )
D.
12
775 a. Calculate e.m.f of cell for the reaction:
( M g_{(s)}+C u^{2+}(0.0001 M) rightarrow )
( M g^{2+}(0.001 M)+C u_{(s)} )
Given that: ( E_{M g^{2+} / M g}^{o}=-2.37 mathrm{V} )
( E_{C u^{2+} / C u}^{o}=+0.34 v )
b. i) State Kohlrausch law.
ii) What is meant by limiting molar
conductance.
12
776 Predict whether the following equation
will take place or not. ( boldsymbol{C u}_{(s)}+mathbf{2 H}_{(a q)}^{+} rightarrow boldsymbol{C u}_{a q}^{2+}+boldsymbol{H}_{2(g)} )
Given that ( boldsymbol{E}_{boldsymbol{C u}^{2+} mid boldsymbol{C u}}^{0}=boldsymbol{0 . 4 4} boldsymbol{V} ; boldsymbol{E}_{boldsymbol{H}^{+} mid boldsymbol{H}_{2}}^{0}= )
0
12
777 The equilibrium constant for the
reaction, ( boldsymbol{S n}(boldsymbol{s})+boldsymbol{2} boldsymbol{H}^{+} rightarrow boldsymbol{S} boldsymbol{n}^{2+}+ )
( boldsymbol{H}_{2}(boldsymbol{g}) boldsymbol{a} boldsymbol{t} boldsymbol{2} boldsymbol{5}^{circ} boldsymbol{C} ) is:
( boldsymbol{E}^{circ}left(boldsymbol{S} boldsymbol{n}^{2+} mid boldsymbol{S} boldsymbol{n}right)=mathbf{0 . 1 4} )
A ( .5 .5 times 10^{4} )
B. ( 2.3 times 10^{2} )
c. ( 1.1 times 10^{2} )
D. 1.009
12
778 toppr
Q Type your question
19 ( m ) ( )
( A )
( B )
( c )
( D )
12
779 ( boldsymbol{C a}, boldsymbol{N a}, boldsymbol{M} boldsymbol{g}, boldsymbol{Z} boldsymbol{n}, boldsymbol{F e}, boldsymbol{H}, boldsymbol{C u}, boldsymbol{H} boldsymbol{g}, boldsymbol{A} boldsymbol{g}, boldsymbol{A} )
Given elements are in order of
decreasing reactivity according to electrochemical series. Half-reaction
possible for the shown electrochemical
cell at the anode is:
A ( cdot C u^{2+}+e^{-} rightarrow C u+ )
B ( cdot Z n(s) rightarrow Z n^{2+}+2 e^{-} )
c. ( Z n^{2+}+2 e^{-} rightarrow Z n(s) )
D. ( C u(s) rightarrow C u^{2+}+2 e^{-} )
E ( cdot C u^{2+}+2 e^{-} rightarrow C u(s) )
12
780 An electric spark is struck between two
electrodes placed near each other, inside a closed tank full of petrol. What’ll happen?
A. Spontaneous combustion of petrol
B. Explosion
c. Slow combustion of petrol
D. Nothing will happen
12
781 During the working of a galvanic cell and with the passage of time:
This question has multiple correct options
A. spontaneity of the cell reaction decreases, ( E_{c c l} ) decreases
B. reaction quotient Q decreases, E ( _{text {cell } text {increases }} )
C . reaction quotient ( Q ) increases, ( E_{c e l l} ) decreases
D. at equilibrium, ( Q=K_{e q}, E_{c e l l}=0 )
12
782 The removal of salt bridge from Daniell cell brings in the following changes:
A ( cdot E_{Z n / Z n^{2+}}^{o} ) changes
B . ( E_{C u / C u^{2+}}^{o} ) changes
C. ( E_{text {clu }}^{o} ) drops to zero
D. none of the above
12
783 The factor which is not affecting the
conductivity of any solution is
A. temperature
B. dilution
c. nature of electrolyte
D. none of the above
12
784 When copper rod donates electrons to
hydrogen ions, it gains charge.
A. positive
B. negative
c. no charge
D. can’t say
12
785 The process in which metal surface is made inactive is called:
A. passivation
B. galvanising
c. corrosion
D. pickling
12
786 Q.41 Solutions of two electrolytes A and B are diluted.
1.5 times while that of A increases 25 times. Which
strong electrolyte ? Justify your answer.
and B are diluted. The Am of ‘B’ increases
lases 25 times. Which of the two is a
otion Therefore,
12
787 Electrolysis is carried out in three cells:
( (A)-1.0 M C u S O_{4}, ) Pt electrodes;
( (B)-1.0 M C u S O_{4}, ) Copper electrodes;
( (C)-1.0 M K C I, ) Pt electrodes. If volume
of
electrolytic solution is maintained
constant in
each of the cells, which is correct set of
( mathrm{pH} )
changes in ( (A),(B) ) and ( (C) ) cells respectively:
A. increase in all the three
B. decrease in all the three
c. increase, constant, increase
D. decrease, constant, increase
12
788 Two faraday of electricity is passed
through a solution of ( C u S O_{4} ). The mass
of copper deposited at the cathode is :
(at mass of ( boldsymbol{C u}=mathbf{6 3 . 5} boldsymbol{u} ) ).
A. ( 127 g )
в. ( 0 g )
c. ( 63.5 g )
D. ( 2 g )
12
789 The reaction which is taking place in
nickel- cadmium battery can be represented by which of the following equation?
A ( cdot C d+N i O_{2}+2 H_{2} O rightarrow C d(O H)_{2}+N i(O H)_{2} )
B. ( C d+N i O_{2}+2 O H^{-} rightarrow N i+C d(O H)_{2} )
c. ( N i+C d(O H)_{2} rightarrow C d+N i(O H)_{2} )
D. ( N i(O H)_{2}+C d(O H)_{2} rightarrow N i+C d+2 H_{2} O )
12
790 Write cell reactions in lead storage battery during discharge. 12
791 A depolariser used in dry cell batteries
is:
A. ammonium chloride
B. manganese dioxide
c. potassuim hydroxide
D. sodium phosphate
12
792 The reduction potential of hydrogen electrode when placed in a buffer solution is found to be -0.413 V. The pH
of the buffer is:
A . 10
B. 4
( c cdot 7 )
D. 12
12
793 In lead-acid battery electrolyte used is:
A. sulphuric acid
B. aqueous solution of ( P b S O_{4} )
c. nitric acid
D. aqueous solution of ( mathrm{FeSO}_{4} )
12
794 The potential of the following cell at
( 25^{circ} C ) is:
( boldsymbol{P t}left|begin{array}{c|c|c}boldsymbol{H}_{2} & boldsymbol{H} boldsymbol{N} boldsymbol{O}_{3} & boldsymbol{N a O H} & boldsymbol{H}_{2} \ (boldsymbol{1} boldsymbol{a} boldsymbol{t m}) & boldsymbol{0} . boldsymbol{1} boldsymbol{M} & mid & left(boldsymbol{1 0}^{-3} boldsymbol{M}right)end{array}right|(boldsymbol{1} boldsymbol{a} boldsymbol{t m}) )
A. ( -0.059 V )
B. ( 0.059 V )
( c .-0.59 V )
D. ( 0.5 V )
12
795 ( E^{o} ) values for the half cell reactions are
given:
( boldsymbol{C u}^{2+}+boldsymbol{e}^{-} rightarrow boldsymbol{C u}^{+} ; boldsymbol{E}^{o}=mathbf{0 . 1 5 V} )
( boldsymbol{C u}^{2+}+mathbf{2} e^{-} rightarrow boldsymbol{C u} ; boldsymbol{E}^{o}=mathbf{0 . 3 4} mathbf{v} )
What will be the ( E^{o} ) of the half-cell:
( boldsymbol{C u}^{+}+boldsymbol{e}^{-} rightarrow boldsymbol{C u} ? )
A . ( +0.49 v )
в. ( +0.19 v )
( c .+0.53 v )
D. ( +0.30 v )
12
796 Question 9. Why is alternating current used for measuring resistance
of an electrolytic solution?
12
797 What transformation of energy takes place when current is drawn from a cell
?
A. Chemical energy changes to electrical energy
B. Chemical energy changes to heat energy
c. mechanical energy changes to electrical energy
D. Chemical energy changes to mechanical energy
12
798 KCI can be used in salt bridge as
electrolyte in which of the following
cells?
( mathbf{A} cdot Z nleft|Z n C l_{2} | A g N O_{3}right| A g )
B . ( P bleft|P bleft(N O_{3}right)_{2} | C uleft(N O_{3}right)_{2}right| C u )
c. ( C uleft|C u S O_{4} | A u C l_{3}right| A u )
D. ( F eleft|F e S O_{4} | P bleft(N O_{3}right)_{2}right| P b )
12
799 During the purification of copper by electrolysis:
This question has multiple correct options
A. the anode used is made of copper ore
B. pure copper is deposited on the cathode
C. the impurities such as ( A g, A u ) present in solution as ions
D. concentration of ( C u S O_{4} ) solution remains constant
during dissolution of ( C u )
12
800 ampere current is passed for 60 seconds into an electrolytic cell. Number
of electrons that pass through the
solution is :
A. ( 6.0 times 10^{23} )
B. ( 1.2 times 10^{24} )
c. ( 37.5 times 10^{19} )
D. ( 7.48 times 10^{21} )
12
801 Calculate the equilibrium constant for
the reaction:
( mathbf{3} boldsymbol{S} boldsymbol{n}(boldsymbol{s})+boldsymbol{2} boldsymbol{C r}_{2} boldsymbol{O}_{7}^{2-}+boldsymbol{2} boldsymbol{8} boldsymbol{H}^{+} rightarrow )
( mathbf{3} boldsymbol{S} boldsymbol{n}^{+mathbf{4}}+mathbf{4} boldsymbol{C} boldsymbol{r}^{mathbf{3}+}+mathbf{1 4} boldsymbol{H}_{mathbf{2}} boldsymbol{O} )
( E^{circ} ) for ( S n / S n^{2+}=0.136 V E^{circ} ) for
( boldsymbol{S} boldsymbol{n}^{2+} / boldsymbol{S} boldsymbol{n}^{4}=-mathbf{0 . 1 5 4} boldsymbol{V} )
( E^{circ} ) for ( C r_{2} O_{7}^{2-} / C r^{3+}=1.33 V ), if the
ans is ( K=10^{c}, ) what is c?
A . 261
в. 273
( c cdot 128 )
D. none of these
12
802 During electrolysis of a salt solution
( 0.05 mathrm{F} ) of electricity deposits ( 1.6 mathrm{g} ) of divalent metal. Theatomic wt. of the
metal is :
A . 32
B. 16
( c cdot 64 )
D. 1.6
12
803 Which of the following is not true about
LED?
A. There are two wires (called leads) attached to an LED.
B. While connecting to a circuit, the longer lead of LED is always connected to the positive terminal of the battery.
C. While connecting to a circuit, the shorter lead of LED is always connected to the positive terminal of the battery.
D. LED can be used to detect weak current.
12
804 Question 20. Write the cell reaction for a lead storage battery when it is
discharge. How does the density of the electrolyte change when the
battery is discharged?
12
805 Calculate the current (in mA) required to deposit ( 0.195 g ) of platinum metal in
5.0 hours from a solution of ( left[boldsymbol{P t} C l_{6}right]^{2-} ) (Atomic weight: ( boldsymbol{C r}=mathbf{5 2 . 0} ) )
A . 310
B. 31
c. 21.44
D. 5.36
12
806 Calculate the e.m.f. (in ( V ) ) of the cell:
( boldsymbol{P t}left|boldsymbol{H}_{2}(boldsymbol{g})right| boldsymbol{B O H}(boldsymbol{a q}) | boldsymbol{H} boldsymbol{A}(boldsymbol{a q})left|boldsymbol{H}_{2}(boldsymbol{g})right| boldsymbol{P} )
Given: ( boldsymbol{K}_{boldsymbol{a}}(boldsymbol{H} boldsymbol{A})=mathbf{1 0}^{-mathbf{7}}, boldsymbol{K}_{boldsymbol{b}}(boldsymbol{B O H})= )
( 10^{-5} )
A . ( 0.43 mathrm{V} )
B . ( 0.36 V )
c. ( 0.93 V )
D. None of these
12
807 The units of conductivity of the solution
are:
( mathbf{A} cdot o h m^{-1} )
B. ohms
( mathbf{c} cdot operatorname{ohm}^{-1} c m^{-1} )
D. ( o h m^{-1} e q^{-1} )
12
808 A fuel cell is:
I.A voltaic cell in which continuous supply of fuels are sent at anode to perform oxidation.
II. A voltaic cell in which fuels such as:
( C H_{4}, H_{2} ) and ( mathrm{CO} ) are used up at anode.
III. One which involves the reaction of
( H_{2} O_{2} ) fuel cell such as:
Anode ( : 2 H_{2}+4 stackrel{ominus}{O} H rightarrow 4 H_{2} O(l)+4 e^{-} )
Cathode ( : O_{2}+2 H_{2} O(l)+4 e^{-} rightarrow 4 stackrel{ominus}{O} H )
IV. The efficiency of ( H_{2}-O_{2} ) fuel cell is 70
to ( 75 % )
A. ( I, I I I )
в. ( I, I I I, I V )
c. ( I, I I, I I I, I V )
D. ( I, I I, I I I )
12
809 If for the half-cell reactions
( boldsymbol{C u}^{2+}+boldsymbol{e}^{-} longrightarrow boldsymbol{C u}^{+} boldsymbol{E}^{o}=mathbf{0 . 1 5} boldsymbol{V} )
( boldsymbol{C u}^{2+}+boldsymbol{2} boldsymbol{e}^{-} longrightarrow boldsymbol{C u} quad boldsymbol{E}^{o}=mathbf{0 . 3 4} boldsymbol{V} )
Calculate ( E^{o} ) of the half cell reaction
( boldsymbol{C u}^{+}+boldsymbol{e}^{-} longrightarrow boldsymbol{C u} )
Also predict whether ( C u^{+} ) undergoes
disproportionation or not
12
810 The maximum amount of electrical
energy that can be obtained from one
mole of ( N_{2} O_{3} ) is :
( mathbf{A} cdot-245.11 k J )
B. -125.10kJ
c . ( -255.43 k J )
D. None of these
12
811 Which of the following methods is suitable for preventing an iron frying pan from rusting?
A. Applying grease
B. Applying paint
C. Applying a coating of zinc
D. All of the above
12
812 State True or False.
Kohlrausch law is valid for weak
electrolytes only.
A. True
B. False
12
813 The correct order of ( A_{e q}^{infty} ) at infinite dilution is:
A . ( operatorname{LiC} mid> ) NaCI ( > ) KCI
B. KCI> NaCI> LiCI
C . NaCI> KCI > LiCI
D. LiCI>KCI> Nacl
12
814 Assertion
Lower parts of the ship or bridge is coated with tar.
Reason
It is to increase rusting.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
815 Consider a fuel cell supplied with 1 mol
of ( H_{2} ) gas and 10 moles of ( O_{2} ) gas. If fuel
cell is operated at 96.3 m ( A ) current, how long will it deliver power? (Assume ( 1 F=96500 C / )mol of
electrons)
( mathbf{A} cdot 1 times 10^{6} s )
B . ( 0.5 times 10^{6} s )
C ( .2 times 10^{6} s )
D. ( 4 times 10^{6} s )
E . ( 5 times 10^{6} )
12
816 Write the equation occurring at anode
in lead battery.
12
817 A certain current liberated 0.504 gm of hydrogen in 2 hrs. How many grams of copper can be liberated by the same current flowing for the same time in a copper sulphate solution?
A. ( 12.7 mathrm{gms} )
B. 15.9 gms
c. ( 31.8 mathrm{gms} )
D. ( 63.5 mathrm{gms} )
12
818 Two platinum electrodes were
immersed in a solution of ( C u S O_{4} ) and electric current was passed through the solution. After some time, it was found
that colour of ( C u S O_{4} ) disappeared with
evolution of gas at the electrode. The colorless solution contains:
A ( . C u S O_{4} )
в. ( H_{2} S O_{4} )
( c cdot operatorname{both} A & B )
D. None of the above
12
819 The value of E for elements are as
follows:
( boldsymbol{F} boldsymbol{e}^{+mathbf{2}}+boldsymbol{2} boldsymbol{e} rightarrow boldsymbol{F} boldsymbol{e} ; boldsymbol{E}^{boldsymbol{o}}=mathbf{0 . 4 4} boldsymbol{V} )
( boldsymbol{F} boldsymbol{e}^{+mathbf{3}}+mathbf{1} boldsymbol{e} rightarrow boldsymbol{F} boldsymbol{e}^{+mathbf{2}} ; boldsymbol{E}^{boldsymbol{o}}=+mathbf{0 . 7 7} boldsymbol{V} )
( boldsymbol{S} boldsymbol{n}^{+mathbf{4}}+boldsymbol{2} boldsymbol{e} rightarrow boldsymbol{S} boldsymbol{n}^{+2} ; boldsymbol{E}^{boldsymbol{o}}=+mathbf{0 . 1 3} boldsymbol{V} )
( boldsymbol{I}_{2}+boldsymbol{2} boldsymbol{e} rightarrow boldsymbol{2} boldsymbol{I} ; boldsymbol{E}^{o}=+mathbf{0 . 5 4} boldsymbol{V} )
( boldsymbol{C r}^{3+}+boldsymbol{3} boldsymbol{e} rightarrow boldsymbol{C r} ; boldsymbol{E}^{o}=mathbf{0 . 7 4} boldsymbol{V} )
Based on the above data correct
statements are:

This question has multiple correct options
A. Strongest reducing agent is ( C r^{3+} )
B. Strongest oxidising agent is ( F e^{3} )
( mathbf{c} cdot S n^{+4} ) can oxidise ( I )
D. ( S n^{+3} ) can oxidise ( I )

12
820 Question below refers to the
overall reaction and half-reactions with
standard reduction potentials below. ( 2 F e^{2+}+C l_{2} rightarrow 2 F e^{3+}+2 C l ? )
( boldsymbol{F e}^{3+}+boldsymbol{e}^{-} rightarrow boldsymbol{F} e^{2+} ; boldsymbol{E}_{r e d}^{o}=0.77 ) volts
( C l_{2}+2 e^{-} rightarrow 2 C l^{-} ; E_{r e d}^{o}=1.36 ) volts
Find the overall potential for the reaction?
A. 0.18 volt
B. 0.59 volts
c. ( 1.05 v o l t s )
D. 2.13voolt
E. 2.90volts
12
821 The half cell involving the reaction ( boldsymbol{C r}_{2} boldsymbol{O}_{mathbf{7}}^{2-}(boldsymbol{a q})+mathbf{1 4 H}^{+}(boldsymbol{a q})+boldsymbol{6} e rightarrow )
( 2 C r^{3+}(a q)+7 H_{2} O ) can be represented
as:
A ( cdot P t, H^{+}(a q), C r_{2} O_{7}^{2-}(a q) )
B . ( P t, H^{+}, C r^{3}+(a q) )
c. ( P t, H_{2}, C r_{2} O_{7}^{2-}(a q), C r^{3+}(a q) )
D. ( P t, H^{+}, C r_{2} O_{7}^{2-}(a q), C r^{3+}(a q) )
12
822 Which of the following statement(s)
is/are true for the process of anodizing?
A. Anodizing is an electrochemical process
B. It converts the metal surface into a decorative, durable, corrosion-resistant, anodic oxide finish.
C. Aluminum is ideally suited to anodizing, although other nonferrous metals, such as magnesium and titanium, also can be anodized.
D. All of the above
12
823 Current efficiency in electroplating is usually:
A . 99%
B. 90 to 98%
c. 70 to ( 80 % )
D. 50 to 60%
12
824 Define the term: Corrosion 12
825 How much will the potential of
( Z n / Z n^{2+} ) change if the solution of
( Z n^{2+} ) is diluted 10 times?
A. increase by ( 0.03 mathrm{V} )
B. decreases by ( 0.03 mathrm{V} )
c. increases by ( 0.059 mathrm{V} )
D. decreases by ( 0.059 mathrm{V} )
12
826 Cell constant of a conductivity cell is
generally obtained by measuring conductance of aqueous solution of
A. ( B a C l_{2} )
в. LiCl
c. ( K C l )
D. ( M g C l_{2} )
12
827 Foe the electrochemical cell:
[
begin{array}{c}
boldsymbol{Z} boldsymbol{n}(boldsymbol{s}) mid boldsymbol{Z} boldsymbol{n}^{2+}(boldsymbol{a} boldsymbol{q}) | \
boldsymbol{C l}^{-}(boldsymbol{a} boldsymbol{q})left|boldsymbol{C l}_{2}(boldsymbol{g})right| boldsymbol{P} boldsymbol{t}(boldsymbol{s}) \
text { Given }: boldsymbol{E}_{boldsymbol{Z n}^{2+} / Z boldsymbol{n}}^{o}=-mathbf{0 . 7 6} boldsymbol{V} boldsymbol{o l t} \
boldsymbol{E}_{boldsymbol{C l}^{prime} / boldsymbol{C l}_{2}(boldsymbol{g})}=-mathbf{1 . 3 6} boldsymbol{V} boldsymbol{o l t} boldsymbol{t}
end{array}
]
From these data one can deduce that:
A ( cdot Z n+C l_{2} rightleftharpoons Z n^{2+}+2 C l^{-} ) is a non-spontaneous
reaction at standard conditions
B . ( Z n^{2+}+2 C l^{-} rightleftharpoons C l_{2}+Z n ) is a spontaneous reaction at
standard conditions with ( E_{c e l l}^{o}=2.12 ) volt.
C. ( Z n+C l_{2} longrightarrow Z n^{2+}+2 C l^{-} ) is a spontaneous reaction
at standard conditions with ( E_{c e l l}^{o}=2.12 ) volt.
D. ( Z n+C l_{2} longrightarrow Z n^{2+}+2 C l^{-} ) is a spontaneous reaction
at standard conditions with ( E_{c e l l}^{o}=0.60 ) volt.
12
828 Select the wrong option about rancidity.
A. Aerial oxidation of fats
B. Aerial oxidation of oils
C . Oils left in refrigerator gets rancid
D. Chips exposed to air gets rancid
12
829 10 g fairly concentrated solution of
( boldsymbol{C u} boldsymbol{S O}_{4} ) is electrolyzed using 0.01 ( mathrm{F} ) of electricity. Calculate:
(a) The weight of resulting solution(g) (write the value to the nearest integer).
12
830 During galvanization of iron, which metal is used for coating iron surface?
A. copper
B. zinç
c. Nickel
D. Tin
12
831 The cell constant of a conductivity cell
with electrodes of ( 0.5 mathrm{cm} times 0.5 mathrm{cm} ) with a
separation of ( 0.5 mathrm{cm}, ) is:
A. ( 0.5 mathrm{cm}^{-1} )
B. ( 2.0 mathrm{cm}^{-1} )
( c .2 .0 mathrm{cm} )
D. ( 2.0 mathrm{cm}^{-2} )
12
832 In Leclanche cell, Zinc rod is placed in:
A ( cdot 10 % ) NH ( _{4} ) С।
B. 20% NH_CI
c. ( 30 % mathrm{NH}_{4} ) С।
D . 40% NH ( _{4} ) C
12
833 The overall formation constant for the
reaction of 6 mole of ( C N^{-} ) with cobalt
(II) is ( 1 times 10^{19} . ) Given that
( boldsymbol{C o}(boldsymbol{C N})_{boldsymbol{6}}^{boldsymbol{3}-}+boldsymbol{e} rightarrow boldsymbol{C o}(boldsymbol{C N})_{boldsymbol{6}}^{boldsymbol{4}-} ; boldsymbol{E}_{boldsymbol{R} boldsymbol{P}}^{boldsymbol{o}}= )
( -0.83 V )
( boldsymbol{C o}^{3+}+boldsymbol{e} rightarrow boldsymbol{C o}^{2+} ; boldsymbol{E}_{R P}^{o}=mathbf{1 . 8 2} boldsymbol{V} )
If the formation constant for the
reaction of 6 mole of ( C N^{-} ) with cobalt
(III) is ( x times 10^{63} ) then ( 100 x )
is
12
834 If ( 9 g ) of ( H_{2} O ) is electrolyzed completely with ( 50 % ) current efficiency:
A. ( 1 F ) of electricity will be needed
B. ( 3 F ) of electricity is needed
c. 5.6 L of ( O_{2} ) at ( S T P ) will be formed
D. ( 11.2 L ) of ( O_{2} ) at ( S T P ) will be formed
12
835 As dilution of the solution increases
then the conductivity of solution
A. increases
B. decreases
c. remain unchanged
D. none of the above
12
836 Iron articles rust readily whereas steel
which is also mainly made of iron will
not undergo corrosion.
A. True
B. False
12
837 Mark the correct statement:
a) Damp air alone supplies both things needed for corrosion.
b) Ordinary water supplies both air and water for corrosion.
c) Moist air can’t provide both things.
( A cdot a, b )
в. а,
( c cdot b, c )
D. All of the above
12
838 When a lead storage battery is discharged, then:
( A cdot mathrm{SO}_{2} ) is evolved
B. lead is formed
c. lead sulphate is consumed
D. sulphuric acid is consumed
12
839 A constant current of ( 30 A ) is passed
through an aqueous solution of ( N a C l )
for a time of ( 1.00 h ). What is the volume
of ( C l_{2} ) gas at STP produced?
A . ( 30.00 L )
B . ( 25.08 L )
c. ( 12.54 L )
D. ( 1.12 L )
12
840 Time required to produce 1 kg of ( C l_{2} ) in
hrs is ( (40+x) . ) Find value of ( x ) (nearest
integer value).
12
841 Q. 63 Assertion (A) Current stops flowing when Ecell = 0.
Reason (R) Equilibrium of the cell reaction is attained.
12
842 Write three methods of preventing rusting of iron. 12
843 Given ( : boldsymbol{H}_{2} boldsymbol{O}_{2} rightarrow boldsymbol{O}_{2}+boldsymbol{2} boldsymbol{H}^{oplus}+boldsymbol{2} boldsymbol{e}^{-} )
( boldsymbol{e}^{oplus}=-mathbf{0 . 6 9} boldsymbol{V} )
( boldsymbol{H}_{2} boldsymbol{O}_{2}+boldsymbol{2} boldsymbol{H}^{oplus}+boldsymbol{2} boldsymbol{e}^{-} rightarrow boldsymbol{2} boldsymbol{H}_{2} boldsymbol{O} )
( boldsymbol{E}^{oplus}=mathbf{1} . mathbf{7 7} boldsymbol{V} )
( mathbf{2} boldsymbol{I}^{ominus} rightarrow boldsymbol{I}_{mathbf{2}}+mathbf{2} boldsymbol{e}^{-} )
( boldsymbol{E}^{ominus}=-mathbf{0 . 5 3 5} boldsymbol{V} )
Assertion: ( H_{2} O_{2} ) acts as an oxidizing
agent for ( boldsymbol{I}^{ominus} )
Reason: ( boldsymbol{E}^{ominus} ) is positive.
A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c. Assertion is true but Reason is false
D. Assertion is false but Reason is true
E. Assertion is false but Reason is true Both Assertion and Reason are false
12
844 stion 14. How much electricity is required in coulomb for the
oxidation of
(i) 1 mole of H2O to O2?
(ii) 1 mole of FeO to Fe2O3?
12
845 In the above cell cathodic cell reaction
and number of electrons involved are:
A ( cdot 2 A g^{+}+2 e^{-} rightarrow 2 A g, 2 e^{-} )
B. ( A g^{+}+e^{-} rightarrow A g, 1 e^{-} )
( mathbf{c} cdot 2 H^{+}+2 e^{-} rightarrow H_{2}, 2 e^{-} )
D. ( H^{+}+e^{-} rightarrow frac{1}{2} H_{2}, e^{-} )
12
846 One ampere of current is passed for
9650 seconds through molten ( A l C l_{3} )
What is the weight in grams of ( boldsymbol{A l} ) deposited at cathode? (Atomic weight of ( A l=27 ) )
A . 0.9
в. 9.
c. 0.09
D. 90.0
12
847 Prevention of corrosion of iron by ( Z n )
coating is called:
A . galvanization
B. cathodic protection
c. electrolysis
D. photoelectolysis
12
848 State True or False.
A cell works if its e.m.f. is negative.
A. True
B. False
12
849 Select incorrect statement
A. If salt-bridge is removed, potential falls to zero
B. Liquid-junction potential developed across the boundary of the two solutions of different concentration cells are used
c. calomel electrode contains calcium chloride solution in contact with ( P t ) electrode
D. Quinhydrone electrode is reversible to ( H^{+} )
12
850 The number of coulombs necessary to deposit ( 1 ~ g ) of potassium metal (molar mass ( 39 g m o l^{-1} ) ) from ( K^{+} ) ions is:
A ( cdot 96500^{circ} mathrm{C} )
B . ( 1.93 times 10^{50} C )
( mathbf{c} cdot 1237^{circ} mathrm{C} )
D. 2474 ( ^{circ} mathrm{C} )
12
851 Which of the following cells can be used to experimentally determine the reduction potential of Zinc?
A ( cdot Z n(s)left|Z n^{2+}(a q)right|left|H^{+}(a q)right| H_{2}(g), P t )
B . ( P t, H_{2}(g)left|H^{+}(a q)right||Z n(s)| Z n^{2+}(a q) )
c. ( Z n(s)left|Z n^{2+}(a q)right|left|C u^{2+}(a q)right| C u(s) )
D. any one of these
12
852 The reaction ( frac{1}{2} times H_{2}(g)+A g C l(a q) rightarrow )
( H^{+}(a q)+A g(s) )
can be represented in the galvanic cell
as:
( mathbf{A} cdot operatorname{Ag} / mathrm{AgCl}(mathrm{s})left|mathrm{KCl}(mathrm{sol}) | mathrm{AgNO}_{3}(mathrm{sol})right| mathrm{Ag} )
B. PtH ( _{2} ) (g) I HCI(sol) II AgNO ( _{3} ) (sol) ( mid ) Ag
C. ( P t, H_{2}(g) mid ) HCI ( (text { sol }) | ) AgCI ( (s) mid A g )
D. ( mathrm{H}_{2}(mathrm{g}) ) | HCI(sol) ( | ) AgCI(s) ( mid ) Ag
12
853 State Faraday’s first law of electrolysis. 12
854 A solution of sodium sulphate in water is electrolysed using inert electrodes.
The products at the cathode and anode are respectively:
A. ( H_{2}, O_{2} )
в. ( O_{2}, H_{2} )
c. ( O_{2}, N a )
D. none of the above
12
855 A voltaic cell converts:
A. electrical energy into chemical energy
B. chemical energy into electrical energy
C. light energy into electrical energy
D. mechanical energy into electrical energy
12
856 Which of the following is correct
regarding mechanical passivity?
A. Visible metal oxide film is formed
B. Visible metal oxide film prevents dissociation of metal
C. Fe, Mn and Pb exhibit mechanical passivity
D. All the above
12
857 Assertion
The ratio of speeds of cation and anions of an electrolyte under same potential gradient is ( 2: 3, ) the fall in concentration around anodic and cathodic solution
will be in the ratio 1: 1 during the passage of current.
Reason
The number of ions discharged at either
electrode during electrolysis in independent of their relative speed.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
858 Write the chemistry of recharging lead storage battery highlighting all the materials that are evolved during recharging. 12
859 018. How will you identify cathode and anode in electrochemical cell? 12
860 When galvanic cell is started, with
passage of time:
This question has multiple correct options
A. spontaneity of the cell reaction decreases; ( E_{c e l l} ) decreases
B. reaction quotient Q decreases; ( E_{text {cell}} ) increases
C . reaction quotient ( mathrm{Q} ) increases; ( E_{c e l l} ) decreases
D. at equilibrium ( Q=K_{c} ; E_{c e l l}=0 )
12
861 Standard electrode potentials of
( boldsymbol{F} boldsymbol{e}^{2+}+boldsymbol{2} boldsymbol{e}^{-} rightarrow boldsymbol{F} boldsymbol{e} ) and ( boldsymbol{F} boldsymbol{e}^{boldsymbol{3}+}+boldsymbol{3} boldsymbol{e}^{-} rightarrow )
( F e ) are ( -0.440 V ) and ( -0.036 V )
respectively. The standard electrode potential ( left(boldsymbol{E}^{o}right) ) for ( boldsymbol{F} boldsymbol{e}^{mathbf{3}+}+boldsymbol{e}^{-} rightarrow boldsymbol{F} boldsymbol{e}^{2+} )
is:
( mathbf{A} cdot-0.476 V )
В. ( -0.404 V )
c. ( +0.404 V )
D. ( +0.772 V )
12
862 Assertion
The ratio of specific conductivity to the observed conductance does not depend upon the concentration of the solution
taken in the conductivity cell.
Reason
The specific conductivity decreases with dilution whereas observed
conductance increases with the
dilution.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
863 Can you store copper sulphate solutions
in a zinc pot?
12
864 Find out the EMF of the following cells at ( 25^{0} mathrm{C} )
( p t, B r_{2(l)}left|B r^{-}(0.010 M)right|left|H^{+}(0.030 M)right| H_{2}(1 a )
( $ $ 1 ) binom ( left{E{{0}}_{-}left{B r_{-}{2} / 2 B r^{wedge}{-}right}=+1.08right. )
( left.V, R=8.314 J K^{wedge}left{-left.1 m oright|^{wedge}{-1}right},right} )
( left{F=96,left.500 C m oright|^{wedge}{-1}right} $ )
A. ( 0.872 v )
( v )
B . -0.872v
c. -1.052v
D. 1.288v
12
865 The conductivity of a saturated solution of ( B a S O_{4} ) is ( 3.06 times 10^{-6} ) ohm ( ^{-1} c m^{-1} )
and its molar conductance is ( 1.53 o h m^{-1} c m^{2} m o l^{-1} . ) The ( K_{s p} ) of
( B a S O_{4} ) will be:
A ( cdot 4 times 10^{-12} )
В. ( 2.5 times 10^{-9} )
c. ( 2.5 times 10^{-13} )
D. ( 4 times 10^{-6} )
12
866 R
1 Which cell will measure standard electrode potential of copper electrode
(a) Pt (s) IH,(g, 0.1 bar) H(aq., 1 M) Cu2+ (aq, 1 M) Cu
(b) Pt (5) Hy(s, 1 bar) H(aq, 1 M) Cu2+(aq, 2 M) Cu
(c) Pt (s) | H (8,1 bar) H(aq, 1 M) Cu2+ (aq, 1 M) Cu
(d) Pt (5)|H2/8, 0.1 bar) H*(aq,0.1 M | Cu2+ (aq, 1 M) Cu
12
867 Edible oils shows rancidity when stored for long period.
A . True
B. False
12
868 At ( 25^{circ} mathrm{C} ), the molar conductances at
infinite dilution for the strong
electrolytes ( N a O H, N a C l ) and ( B a C l_{2} )
( operatorname{are} 248 times 10^{-4}, 126 times 10^{-4} ) and ( 280 times )
( 10^{-4} S m^{2} m o l^{-1} ) respectively
( lambda_{m}^{circ} B a(O H)_{2} ) in ( S m^{2} m o l^{-1} ) is
( mathbf{A} cdot 52.4 times 10^{4} )
B ( .524 times 10^{4} )
c. ( 4.2 times 10^{4} )
D ( .262 times 10^{4} )
12
869 Which of the following might be the
reason that the current in the circuit is
weak?
A. Circuit of the tester might not be complete
B. The material may not be able to conduct electricity as easily as metals.
c. The circuit of the tester is complete but still the bulb does not glow.
D. Both A and B
12
870 Rusting of iron is catalysed by which of the following:
A . ( F e )
в. ( Z n )
( c cdot 0_{2} )
( mathbf{D} cdot H^{+} )
12
871 The standard reducation potentials of ( Z n^{2+}left|Z n, C u^{2+}right| C u ) and ( A g^{+} mid A g )
are respectively -0.76,0.34 and ( 0.8 mathrm{V} ). The following cells were constructed.
a) ( Z nleft|Z n^{2+}right|left|C u^{2+}right| C u )
b) ( Z nleft|Z n^{2+} | A g^{+}right| A g )
c) ( C uleft|C u^{2+}right|left|A g^{+}right| A g )
What is the correct order ( E_{text {cell }}^{0} ) of these cells?
( A cdot ) b>c ( >a )
B. b>a>c
( c cdot a>b>c )
D. c>asb
12
872 Assertion
Polished iron nails do not rust when
kept immersed in a test tube
containing boil water covered with a
layer of oil.
Reason
Rust formation can be controlled with
coatings such as paint or varnish that isolate the iron from environment. When
only temporary protection is needed for
storage or transport a thin layer of oil, grease can be applied to an iron
surface
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
873 The emf of a cell corresponding to the reaction,
( Z n+2 H^{+}(a q .) rightarrow Z n^{2+}(0.1 M)+ )
( H_{2}(g) 1 a t m )
is 0.28 volt at ( 25^{circ} mathrm{C} ). Write the half-cell
reactions and calculate the ( p H ) of the
solution at the hydrogen electrode.
( boldsymbol{E}_{boldsymbol{Z n}^{2+} / boldsymbol{Z n}}^{circ}=-mathbf{0 . 7 6} boldsymbol{v o l t} ) and ( boldsymbol{E}_{boldsymbol{H}^{+} / boldsymbol{H}_{2}}^{circ}=boldsymbol{0} )
12
874 The emf of a galvanic cell, with electrode potentials of ( Z n=+0.76 V )
is:
A ( .-1.1 V )
B. ( +1.1 V )
( mathbf{c} .+0.34 V )
D. ( +0.76 V )
12
875 The methods used in protecting the
metals are:
A. galvanizing
B. alloying
c. electroplating
D. all of these
12
876 State True or False.
Electrolysis of molten ( K C l ) gives ( mathrm{Cl}_{2} ) at
cathode.
A. True
B. False
12
877 Assertion
The Daniell cell becomes dead after
some time.
Reason
Oxidation potential of zinc anode decreases and that of copper increases.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
878 For the following half cell reactions, ( boldsymbol{E}^{boldsymbol{o}} ) values are also given:
( M n^{2+}+2 H_{2} O rightarrow M n O_{2}+4 H^{+}+ )
( mathbf{2} e^{-} ; quad boldsymbol{E}^{o}=-mathbf{1 . 2 3} mathbf{V} )
( M n O_{4}^{-}+4 H^{+}+3 e^{-} rightarrow M n O_{2}+ )
( 2 H_{2} O ; quad E^{o}=+1.70 V )
Select the correct statements.
A. ( M n^{2+} ) reacts with ( M n O_{4}^{-} ) in acid solution to form ( M n O_{2} )
в. ( M nleft(M n O_{4}right)_{2} ) is stable in acid solution
c. ( M n O_{2} ) disproportionates to ( M n^{2+} ) and ( M n O_{4}^{-} ) in acid solution
D. None of the above
12
879 Calculate the emf of the following
concentration cell at ( 25^{circ} C )
( boldsymbol{A} boldsymbol{g}(boldsymbol{s}) mid boldsymbol{A} boldsymbol{g} boldsymbol{N} boldsymbol{O}_{3}(mathbf{0} . boldsymbol{0} mathbf{1} boldsymbol{M}) )
( boldsymbol{A} boldsymbol{g} boldsymbol{N} boldsymbol{O}_{3}(boldsymbol{0} . boldsymbol{0} boldsymbol{5} boldsymbol{M}) mid boldsymbol{A} boldsymbol{g}(boldsymbol{s}) )
A. ( -0.414 V )
в. ( 0.828 V )
c. ( 0.414 V )
D. ( 0.0414 V )
12
880 Standard electrode potential of cell
( boldsymbol{H}_{2}left|boldsymbol{H}^{+} | boldsymbol{A} boldsymbol{g}^{+}right| boldsymbol{A} boldsymbol{g} ) is :
A. ( 0.8 mathrm{v} )
в. ( -0.8 V )
c. ( -1.2 V )
D. ( 1.2 V )
12
881 The number of Faradays required to
produce 0.5 mol of free metal from ( mathbf{A} mathbf{l}^{mathbf{3}+} )
is
( A cdot 3 )
B. 2
( c cdot 6 )
D. 1.5
12
882 toppr
Q Type your question
conductivity of theses reactions is
given in List II. Match List I with List II
and select the correct using the code
given below the lists:
List-A
( (P) )
(1) Conductivity decreases and
[
left(begin{array}{cc}
left.C_{2} H_{5}right)_{3} N+ & text { then increases } \
X &
end{array}right.
]
[
C H_{2} C O O H
]
(Q)
(2) Conductivity decreases and
[
begin{array}{c}
K I(0.1 M)+ \
X
end{array}
]
[
begin{array}{c}
A g N O_{3}(0.01 M) \
Y
end{array}
]
(R)
(3) Conductivity increases and ( C H_{2} C O O+quad ) then does not change much ( K_{Y}^{O H} )
(4) Conductivity does not
(S) ( N a O H+quad ) change much and then [ X ] ( H I )
( Y )( quad ) increases
A. 3,4,2,1
B. 4,3,2,1
C. 2,3,4,1
D. 1,4,3,2
12
883 The equivalent conductances of two strong electrolytes at infinite dilution in
( H_{2} O ) (where ions move freely through a
solution) at ( 25^{circ} mathrm{C} ) are given below
[
boldsymbol{C H}_{3} boldsymbol{C O O N a}=91.0 boldsymbol{S c m}^{2} / boldsymbol{e q u i v}
]
( H C l=426.2 mathrm{Scm}^{2} / )equiv
What additional information/quantity one needs to calculate the equivalent conductances an aqueous solution of acetic acid?
A. The limiting equivalent conductance of Naç
B. The limiting equivalent conductance of ( mathrm{CH}_{3} mathrm{COOH} )
C. The limiting equivalent conductance of ( mathrm{H}^{+} )
D. The limiting equivalent conductance of chloroacetic ( operatorname{acid}left(mathrm{ClCH}_{2} mathrm{COOH}right) )
12
884 Which battery is used in aeroplanes?
A. Dry cell battery.
B. Lead acid battery.
c. Edission cell.
D. None of them.
12
885 Name the law or principle to which the following observations confirm:
(1) When water is added to a ( 1.0 M )
aqueous solution of acetic acid, the
number of hydrogen ion ( left(boldsymbol{H}^{+}right) )
increases.
(2) When 9650 coulombs of electricity is passed through a solution of copper sulphate, ( 3.175 g ) of copper is deposited on the cathode (atomic weight of ( boldsymbol{C u}= )
63.5)
(3) When ammonium chloride is added
to a solution of ammonium hydroxide, the concentration of hydroxyl ions
decreases.
12
886 For hydrogen-oxygen fuel cell, the cell reaction is:
( mathbf{2} boldsymbol{H}_{mathbf{2}}(boldsymbol{g})+boldsymbol{O}_{2}(boldsymbol{g}) longrightarrow mathbf{2} boldsymbol{H}_{2} boldsymbol{O}(boldsymbol{l}) )
If ( Delta G_{f}^{o}left(H_{2} Oright)=-237.2 k J m o l^{-1}, ) then
emf of this cell is:
A . ( +2.46 V )
в. ( -2.46 V )
c. ( +1.23 V )
D. ( -1.23 V )
12
887 The unit of molar conductivity is
A ( cdot operatorname{scm}^{2} s^{-1} )
B . ( mathrm{S} l^{2} mathrm{mol}^{-1} )
c. ( operatorname{scm}^{2} m o l^{-1} )
D. None of these
12
888 For the strong electrolytes NaOH, NaCl
and ( B a C l_{2}, ) the molar ionic
conductances at infinite dilution are
( 248 times 10^{-4}, 126.5 times 10^{-4} ) and ( 280.0 x )
( 10^{-4} mathrm{s} m^{2} m o l^{-1}, ) respectively. Calculate ( wedge_{m}^{0} ) for ( B a(O H)_{2} )
12
889 Which of the following solution of ( N a C l ) has the higher specific conductance?
A. ( 1 N )
B. ( 0.01 N )
( c cdot 0.1 N )
D. ( 0.001 N )
12
890 For the cell ( Z n(s)left|Z n^{2+}right|left|C u^{2+}right| C u(s) )
the standard cell voltage, ( boldsymbol{E}_{c e l l}^{ominus} ) is ( 1.10 mathrm{V} ) When a cell using these reagents was prepared in the lab, the measured cell voltage was ( 0.98 mathrm{V} ). One possible explanation for the observed voltage is :
A. There were 2.00 mol of ( Z n^{2+} ) but only 1.00 mol of ( C u^{2} )
B. The Zn electrode had twice the surface of the cu electrode
C. The ( left[Z n^{2+}right] ) was larger than the ( left[C u^{2+}right] )
D. The volume of the ( left[Z n^{2+}right] ) solution was larger than the volume of the ( C u^{2+} ) solution
12
891 The concentration of ( Z n^{2+} ) in first
compartment after passage of ( 0.1 F )
charge will be:
A ( .1 ~ M )
В. 1.05 М
c. 1.025 М
D. ( 0.5 ~ M )
12
892 The amount of charge which the battery must have been used is:
A ( .9 .88 F )
в. ( 8.98 F )
c. ( 8.89 F )
D. ( 7.88 F )
12
893 What are Galvanic cells? Explain the working of Galvanic cells with one example. 12
894 The half-cell reaction is the one that:
A. takes place at one electrode
B. consumes half a unit of electricity
C. involves half a mole of electrolyte
D. goes half way to completion
12
895 How many no. of metals among the following obtained from molten salt
Electrolysis of their chlorides, oxides or hydroxides ( mathrm{Cu}, mathrm{Ag}, mathrm{Ba}, mathrm{Na}, mathrm{Zn}, mathrm{Fe}, mathrm{Cs} )
12
896 Molten ( A l C l_{3} ) is electrolysed with the current of 0.5 empere to produced 27 g
Al. Number of Farady used are:
( A cdot 3 )
B. 5
( c .6 )
D. None of these
12
897 The voltage of the cell given below is
( -0.46 V )
( boldsymbol{P t}left|begin{array}{cc}boldsymbol{N a H} boldsymbol{S O}_{3} & boldsymbol{N a}_{2} boldsymbol{S O}_{3} \ boldsymbol{0 . 4} boldsymbol{M} & boldsymbol{6 . 4 4} times mathbf{1 0}^{-3} boldsymbol{M}end{array}right|left|begin{array}{c}boldsymbol{Z} boldsymbol{n}^{2+} \ boldsymbol{0} . boldsymbol{3} boldsymbol{M}end{array}right| )
Also, ( Z n^{2+}+2 e rightarrow Z n(s) ; E^{o}= )
( -0.763 V )
The value of ( boldsymbol{K}_{2} ) where ( boldsymbol{K}_{2}= ) ( frac{left[boldsymbol{H}^{+}right]left[boldsymbol{S O}_{3}^{2-}right]}{left[boldsymbol{H} boldsymbol{S O}_{3}^{-}right]} mathbf{i s} )
A . ( 6.44 times 10^{-8} )
B. ( 5.43 times 10^{-8} )
c. ( 7.34 times 10^{-8} )
D. None of these
12
898 What is corrosion?
A. When metal is gradually destroyed through chemical reactions
B. When metal is created through chemical reactions
C. When a redox reaction takes place
D. When a metal is destroyed after exposure to a gas
E. When a solid is destroyed through chemical reactions
12
899 ( mathbf{1 0} C l^{-}(a q)+2 M n O_{4}^{-}(a q)+ )
( mathbf{1 6} boldsymbol{H}^{+}(boldsymbol{a} boldsymbol{q}) rightarrow mathbf{5} boldsymbol{C l}_{2}(boldsymbol{g})+ )
( 2 M n^{2+}(a q)+8 H_{2} O(l) )
The value of ( E^{o} ) for the above reaction at
( 25^{circ} mathrm{C} ) is ( 0.15 mathrm{V} ). Hence, the value of ( mathrm{K} ) for
this reaction is :
A . ( 2.4 times 10^{25} )
B . ( 4.9 times 10^{12} )
c. ( 1.2 times 10^{15} )
D. ( 3.4 times 10^{20} )
12
900 List I
A) Salt bridge
Reduction
B) Standard hydrogen electrode 2 )
Oxidation
C) Cathode
3) Reference
electrode
D) Anode
4) ( mathrm{KCl}, mathrm{KNO}_{3} )
( (text { or }) mathrm{NH}_{4} mathrm{NO}_{3} )
The correct match is :
A. 3421
B. 4 312
c. 4321
D. 1234
12
901 The measured resistance of a
conductance cell was ( 100 Omega .left(M_{K C l}=right. )
( 74.5 g m o l^{-1} ) and cell constant ( = )
( 1.25 mathrm{cm}^{-1} ) ). If the specific conductance
( operatorname{in} operatorname{oh} m^{-1} c m^{-1} ) is ( 125 times 10^{-x}, ) then
what is the value of ( x ? )
12
902 toppr
( Q ) туре
A large number of atoms/molecules (approximately ( 6.023 times 10^{23} ) ) are
present in few grams of any chemical compound varying with their atomic/molecular masses. To handle
such large numbers conveniently, the mole concept was introduced. This concept has implications in diverse areas such as analytical chemistry, biochemistry, electrochemistry, and radiochemistry. the following example illustrates a typical case, involving chemical/electrochemical reaction,
which requires a clear understanding of the mole concept.

A 4.0 molar aqueous solution of NaCl is prepared and ( 500 mathrm{mL} ) of this solution is electrolyzed. This leads to the evolution of chlorine gas at one of the electrodes (atomic mass: ( mathrm{Na}=23, mathrm{Hg}=200 ; 1 )
faraday =96500 coulombs) The total charge (coulombs) required for complete electrolysis is:
A . 24125
B. 48250
c. 96500
D. 193000

12
903 Consider the statements ( $ 1 ) and ( s 2: )
S1: Conductivity always increases with decrease in the concentration of
electrolyte.
S2: Molar conductivity always increases with decrease in the concentration of
electrolyte.

The correct option among the following is:
A. Both S1 and S2 are correct
B. s1 is wrong and s2 is correct
( c . ) s1 is correct and s2 is wrong
D. Both S1 and S2 are wrong

12
904 The standard half cell reduction
potential for ( A g^{+} mid A g ) is ( 0.7991 V ) at
( 25^{circ} mathrm{C} . ) Given that the experimental value
of ( boldsymbol{K}_{s p}=mathbf{1 . 5 6} times mathbf{1 0}^{-mathbf{1 0}} ) for ( boldsymbol{A} boldsymbol{g} boldsymbol{C l} )
calculate the standard half cell
reduction potential for the ( boldsymbol{A} boldsymbol{g} mid boldsymbol{A} boldsymbol{g} boldsymbol{C l} )
electrode.
A ( .0 .2192 V )
В. ( -0.2192 mathrm{V} )
c. ( -1.2192 mathrm{V} )
D. ( 1.219 V )
12
905 Negative terminal of a dry cell is formed
by:
A. zinc container
B. carbon rodd
c. graphite rod
D. both A and B
12
906 When electrolysis of ( K C l ) is done in
alkaline medium, 10 g of ( K C l O_{3} ) is produced as follows:
( boldsymbol{C l}^{ominus}+mathbf{6} stackrel{ominus}{boldsymbol{O}} boldsymbol{H} rightarrow boldsymbol{C l} boldsymbol{O}_{3}^{ominus}+mathbf{3} boldsymbol{H}_{2} boldsymbol{O}+boldsymbol{6} boldsymbol{e}^{-} )
A current of 2 A is passed for 10.941 hours. The current efficiency (in %) used in the process is ( ( M w t o f K C l O_{3}= ) 122.5
12
907 The cost of electricity required to deposit ( 1 g m ) of ( M g ) is ( R s .5 . . ) How much would it cost to deposit 10 gm. of
( A l ?(A t w t . A l=27, M g=24) )
A. ( R s .10 .00 )
B. Rs. 27.00
c. ( R s .44 .44 )
D. Rs. 66.67
12
908 A solution is one molar in each of
( N a C l, C d C l_{2}, Z n C l_{2} ) and ( P b C l_{2} . ) To
this, tin metal is added. Which of the
following is true? Given:
( boldsymbol{E}_{boldsymbol{P b}^{2+} / boldsymbol{P b}}^{circ}=-mathbf{0 . 1 2 6} boldsymbol{V}, boldsymbol{E}_{boldsymbol{S n}^{2+} / boldsymbol{S} n}^{circ}= )
( -mathbf{0 . 1 3 6} boldsymbol{V} )
( boldsymbol{E}_{boldsymbol{C d}^{2+} / boldsymbol{C d}}^{circ}=-mathbf{0 . 4 0} boldsymbol{V}, boldsymbol{E}_{Z n^{2+} / Z n}^{circ}= )
( -mathbf{0 . 7 6 3} boldsymbol{V}, boldsymbol{E}_{N a^{+} / N a}^{circ}=-mathbf{2 . 7 1} boldsymbol{V} )
A. ( S n ) can reduce ( N a^{+} ) to ( N a )
B. ( S n ) can reduce ( Z n^{2+} ) to ( Z n )
( mathrm{c} cdot operatorname{Sn} ) can reduce ( C d^{2+} ) to ( C d )
D. ( S n ) can reduce ( P b^{2+} ) to ( P b )
12
909 of
Q. 18 The positive value of the standard electrode potential
Cu2+ / Cu indicates that………..
(a) this redox couple is a stronger reducing agent than the H /H, couple
(b) this redox couple is a stronger oxidising agent than H+ /H,
(c) Cu can displace H, from acid
(d) Cu cannot displace H, from acid
12
910 Fill in the blanks by choosing the appropriate word/words from those given in the brackets:
(increases, decreases, positive, efficient, ( 68, ) non-efficient, no ( alpha )
hydrogen, ( alpha ) -hydrogen, negative, Rosenmund’s, greater, Cannizzaro, 74 common-ion effect, lesser, buffer action, diamagnetic, paramagnetic) The more is standard reduction
potential of a metal, the is its
ability to displace hydrogen from acids.
12
911 How much silver will be obtained by that quantity of current which displaces
5.6 litre of ( boldsymbol{H}_{2} ) ?
A . ( 54 g )
в. ( 13.5 g )
c. ( 20 g )
D. ( 108 g )
12
912 Which of the following does not produce
( mathrm{H}_{2} ) at the anode on electrolysing using
Pt electrode?
This question has multiple correct options
A . molten CaH ( _{2} )
B. ( N a C l(a q) )
( c cdot operatorname{cus} 0_{4}(a q) )
D. ( operatorname{dil} mathrm{H}_{2} mathrm{SO}_{4} )
12
913 What should be the state of compounds which decompose on passing electric current?
A. Plasma
B. Solid
c. Gas
D. Molten or aqueous
12
914 One gram atomic weight of metal of the following can be deposited by one Faraday:
( mathbf{A} cdot ) AuCl ( _{3} )
B. Bacla
c. Nacı
D. cuso
12
915 At ( 298 mathrm{K} ), the standard reduce
potentials are ( 1.51 mathrm{V} ) for ( mathrm{MnO}_{4}^{-}, 1.36 mathrm{V} ) for ( boldsymbol{C l} boldsymbol{l}_{2} mid boldsymbol{C l}^{-}, 1.07 mathrm{V} ) for ( boldsymbol{B} boldsymbol{r}_{2} mid boldsymbol{B r}^{-}, 0.54 mathrm{V} ) for
( I_{2} mid I^{-} . ) At ( p H=3, ) permangnate is expected to oxidize:
( left(frac{R T}{F}=0.059right) )
A ( . C l^{-} ) and ( B r^{-} )
B. ( B r^{-} ) and ( I^{-} )
c. ( I^{-} ) only
D. ( C l^{-}, B r^{-} ) and ( I^{-} )
12
916 The number of coulombs required to deposit ( 5.4 g ) of Aluminium when the
given electrode reaction is represented
as ( A l^{3+}+3 e^{-} rightarrow A l )
A ( cdot 1.83 times 10^{5} C )
в. ( 57900 C )
( mathbf{c} cdot 5.86 times 10^{5} C )
D. ( 3 F )
12
917 List ( A ) List ( mathrm{B} )
A. Dry Cell
(P) Primary cell
B. Lead storage battery
(Q) ( 38 % H_{2} S O_{4} )
C. Ni-Cd cell
( (mathrm{R}) M n O_{2}+C )
D. ( H_{2}-O_{2} ) fuel cell
(S) Secondary cell
A ( cdot ) A-P,R: B-Q,S:C-S:D-S
B. A-Q,R: B-P,S:C.C-P:D-Q
c. A-P, B-S:C-P,S :D-Q,R
D. A-R: B-Q:C-Q,S:D-P
12
918 Assertion: At infinite dilution, both strong and weak electrolyte have degree of ionization equal to unity. Reason: At infinite dilution of an
electrolyte, the equivalent conductance
of cations and anions are
independent of each other.
A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c. Assertion is true but Reason is false
D. Assertion is false but Reason is true
E. Both Assertion and Reason are false
12
919 When hydrogen sulphide gas is passed through a blue solution of copper sulphate, a black precipitate of copper sulphide is obtained and the sulphuric acid so formed remains in the solution.
The reaction is an example of:
A. a combination reaction
B. a displacement reaction
c. a decomposition reaction
D. a double displacement reaction
12
920 The potential of a single electrode
depends upon:
A. the nature of the electrode
B. Temperature
C. concentration of the ion with respect to which it is reversible
D. all the above
12
921 Number of faradays’ required to generate one gram atom of magnesium
from molten ( M g C l_{2} ) is
A . 1
B . 2
( c .3 )
D.
12
922 Which one of the following cells can convert chemical energy of ( O_{2} ) and ( H_{2} )
directly into electrical energy:
A. mercury cell
B. danicell cell
c. fuel cell
D. lead storage cell
12
923 In which reactants are not contained
within the cell but are continuously supplied from external source?
A. Fuel cell
B. Dry cell
c. Lithium battery
D. Lead storage battery
12
924 The EMF of the cell;
( mathbf{M g}left|mathbf{M g}^{2+}(mathbf{0 . 0 1} mathbf{M}) | mathbf{S n}^{2+}(mathbf{0 . 1} mathbf{M})right| mathbf{S} mathbf{n} )
is:
( left(text { Given: } mathbf{E}_{mathbf{M g}^{2+}, mathbf{M g}}^{circ}=-mathbf{2 . 3 4} mathbf{V}, mathbf{E}_{mathbf{S n}^{2+}, mathbf{S n}}^{circ}=right. )
( -0.14 V) )
( mathbf{A} cdot 2 cdot 17 V )
в. ( 2.23 mathrm{V} )
c. ( 2.51 V )
D. ( 2.45 V )
12
925 For the half cell ( E^{o}=1.30 V . ) At ( p H=3 )
electrode potential is:
A . ( 1.30 V )
B. ( 1.20 V )
c. ( 1.10 V )
D . ( 1.48 V )
12
926 A current of 3 A has to be passed through a solution of silver nitrate for
( t^{prime} ) sec to coat a metal surface of ( 80 mathrm{cm}^{2} )
with a 0.005 -mm-thick layer, then ( t ) is:
(density of silver is 10.5 g ( c m^{-3} ) ) (write
your answer to nearest integer)
12
927 In hydrogen-oxygen fuel cell the carbon rods are immersed in hot aqueous
solution of.
A . ( K C l )
в. КОН
c. ( H_{2} S O_{4} )
D. ( N H_{4} C l )
12
928 refers to amount of electricity
while ( quad ) refers to rate at which it
flows.
A. Ampere, coloumb
B. Coloumb, ampere
c. Faraday, coloumb
D. Coloumb, faraday
12
929 Give the equation for the discharge of ion at the cathode during the electrolysis of acidified water? 12
930 The value of ( wedge_{m}^{infty} ) for ( K C l ) and ( K N O_{3} ) are
149.86 and ( 154.96 Omega^{-1} c m^{2} m o l^{-1} )
respectively. Also ( lambda_{C l^{-}}^{infty} ) is 71.44 ohm ( ^{-1} mathrm{cm}^{2} ) mol ( ^{-1} ). The value of
( lambda_{N O_{3}^{-}}^{infty} ) is :
A ( cdot 76.54 ) ohm ( ^{-1} mathrm{cm}^{2} ) mol ( ^{-1} )
в. 133.08 ohm ( ^{-1} mathrm{cm}^{2} mathrm{mol}^{-1} )
c. 37.7 ohm ( ^{-1} mathrm{cm}^{2} ) mol ( ^{-1} )
D. none of the above
12
931 The cost at 5 paise / KWH of operating an
electri
motor for 8 hours which takes 15 ampere
at ( 110 mathrm{V} ) is:
A. Rs.66
B. 66 paise
c. 37 paise
D. Rs.6.60
12
932 Refining and extraction of metals from impure samples is called:
A. electroplating
B. cathodization
c. electrorefining
D. anionization
12
933 Total world production of iron destroyed by rusting is about:
A . ( 10 % )
B. 50 %
c. ( 15 % )
D. 40 %
12
934 Assertion
Inert electrolytes like KCI ( , K N O_{3} ) are
used in salt bridge.
Reason
Salt bridge provides an electric contact between the two solutions without
allowing them to mix with each other
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
935 Standard E.M.F. experienced by the person with dental filling is:
A . ( +3.89 V )
B . ( 2.89 V )
c. ( 0.93 V )
D. ( +0.43 V )
12
936 Q11. What is a standard hydrogen electrode?
Clabu
12
937 On passing a current through a molten aluminium chloride for some time
produced 11.28 lit of ( C l_{2} ) at ( mathrm{NTP} ) at anode.
The quantity of aluminium deposited at
cathode is:
A. 27grams
B. 18gram
c. ( operatorname{ggram} )
D. 36 gram
12
938 For the redox reaction ( Z n(S)+C u^{2+}(0.1 M) rightarrow )
( Z n^{2+}(1 M)+C u(s) ) taking place in a cell, ( E_{c e l l}^{0} ) is
1.10 volt. ( E_{text {cell}} ) for the cell will be:
( left(2.303 frac{R T}{F}=0.0591right) )
( mathbf{A} cdot 2 cdot 14 V )
B. ( 1.80 V )
c. ( 1.07 V )
D. ( 0.82 V )
12
939 Q12. What is meant by cell potential?
T
.
1
12
940 What is meant by galvanizing? 12
941 The molar conductivities of ( K C l, N a C l )
and ( K N O_{3} ) are 152,128 and
( 111 S c m^{2} m o l^{-1} ) respectively. What is
the molar conductivity of ( N a N O_{3} ? )
( mathbf{A} cdot 101 S mathrm{cm}^{2} mathrm{mol}^{-1} )
B. ( 87 S mathrm{cm}^{2} mathrm{mol}^{-1} )
c. ( -101 S mathrm{cm}^{2} mathrm{mol}^{-1} )
D. ( -391 S mathrm{cm}^{2} mathrm{mol}^{-} )
12
942 When iron is rusted, it is :
A. reduced
B. oxidised
c. evaporated
D. decomposed
12
943 A reaction:
( frac{1}{2} H_{2}(g)+A g C l(s) rightleftharpoons H^{oplus}(a q)+ )
( C l^{ominus}(a q)+A g(s) ) occurs in a galvanic
cell.
The structure of the cell will be:
A ( cdot A g, A g C l(s)|K C l(s o l)| A g N O_{3}(s o l), A g )
B . ( P t, H_{2}(g)|H C l(s o l)| A g N O_{3}(s o l), A g )
c. ( P t, H_{2}(g)|H C l(s o l)| A g C l(s), A g )
D. ( P t, H_{2}(g)|K C l(s o l)| A g C l(s), A g )
12
944 How much time will it take for a
uniform current of ( 6.00 mathrm{A} ) to deposit ( 78 mathrm{g} )
of gold from a solution of ( A u C l_{4}^{-} ? ) What mass of chlorine gas will be
formed simultaneously at the anode of the cell?
(Atomic mass of ( A u=197 ) )
A ( cdot t=3010 sec , w=35.50 g )
B. ( t=20306 sec , w=45.54 g )
c. ( t=19500 ) sec ( , w=54.5 g )
D. ( t=19139.16 sec , w=42.24 g )
12
945 In the electroysis of ( A g N O_{3} ) solution,
( 0.7 mathrm{g} ) of ( mathrm{Ag} ) is deposited after a certain period of time. Calculate the quantity of electricity required in coulomb. (Molar mass of ( A g ) is ( 107.9 g ) mol ( ^{-1} ) ).
12
946 State the first and second law of
electrolysis.
12
947 Ans.(
• 24 What will happen during the electrolysis of aqueous solution or cu
the electrolysis of aqueous solution of CuSO4 in
the presence of Cu electrodes?
(a) Copper will deposit at cathode (b) Copper will dissolve at anode
(C) Oxygen will be released at anode (d) Copper will deposit at anode
12
948 What make(s) water conducting?
A. Salts
B. Hydrogen
c. oxygen
D. None of the above
12
949 An aqueous solution of NaCl on
electrolysis gives ( boldsymbol{H}_{2(g)^{prime}}, boldsymbol{C l}_{2(g)} ) and
NaOH according to the reaction
( mathbf{2} C l_{(a q)}^{-}+mathbf{2} boldsymbol{H}_{2} boldsymbol{O} rightleftharpoons mathbf{2} boldsymbol{O} boldsymbol{H}_{(a q)}^{-}+boldsymbol{H}_{2(g)}+ )
( C l_{2(g)} )
A direct current of 25 amperes with a current efficiency of ( 62 % ) is passed through 20 liters of NaCl solution (20% by weight). Write down the reactions taking place at the anode and the cathode. How long will it take to produce ( 1 mathrm{kg} ) of ( C l_{2} ? ) in hrs. (write the value to the nearest integer).
12
950 The anodic half-cell of lead-acid battery
is recharged unsing electricity of 0.05
Faraday. The amount of ( P b S O_{4} )
electrolyzed in g during the process is :
(Molar mass of ( boldsymbol{P b S O}_{4}=mathbf{3 0 3 g m o l}^{-1} ) )
A . 22.8
B. 15.2
( c .7 .6 )
D. 11.4
12
951 Calculate the cell potential ( left(E_{c e l l}right) ) of the
following cell at ( 298 K )
( boldsymbol{A} boldsymbol{g}(boldsymbol{s}) mid boldsymbol{A} boldsymbol{g} boldsymbol{N} boldsymbol{O}_{3}(boldsymbol{0} . boldsymbol{0} mathbf{1} boldsymbol{M}) | boldsymbol{A} boldsymbol{g} boldsymbol{N} boldsymbol{O}_{3}(mathbf{1} . boldsymbol{0} boldsymbol{M} )
12
952 Which of the following is the cell reaction that occurs when the following half-cells are combined?
( boldsymbol{I}_{2}+boldsymbol{2} boldsymbol{e}^{-} rightarrow boldsymbol{2} boldsymbol{I}^{-}(boldsymbol{1} boldsymbol{M}) ; boldsymbol{E}^{o}=+boldsymbol{0 . 5 4} mathbf{V} )
( boldsymbol{B} boldsymbol{r}_{2}+boldsymbol{2} boldsymbol{e}^{-} rightarrow boldsymbol{2} boldsymbol{B} boldsymbol{r}^{-}(boldsymbol{1} boldsymbol{M}) ; boldsymbol{E}^{o}=+mathbf{1} . boldsymbol{0} boldsymbol{9} )
( mathbf{V} )
A ( cdot 2 B r^{-}+I_{2} rightarrow B r_{2}+2 I^{-} )
В ( cdot I_{2}+B r_{2} rightarrow 2 I^{-}+2 B r^{-} )
c. ( 2 I^{-}+B r_{2} rightarrow I_{2}+2 B r )
D. ( 2 I^{-}+2 B r^{-} rightarrow I_{2} B r_{2} )
12
953 Calculate the standard EMF of the
following cell ( boldsymbol{C} boldsymbol{d}left|boldsymbol{C} boldsymbol{d}^{2+} | boldsymbol{A} boldsymbol{g}^{+}right| boldsymbol{A} boldsymbol{g} )
Given that ( boldsymbol{E}_{boldsymbol{C d}^{2+} mid boldsymbol{C d}}^{boldsymbol{o}}= )
( -mathbf{0 . 4 0} V, E_{A g^{o} mid A g}^{o}=mathbf{0 . 8 V} )
12
954 0.22 AH,0 is equal to…….
(a) Amen + AINAOH – ANSCH (b) AmHNO + AMIN.NO – ANO
(c) AmiHNO, + AINOH – AmiNaNO (d) AMINHOH) + Am(HCI- AmiNH.CH
Thinking Process
This problem includes concept of Kohlrausch law and its application in determination
of molar conductivity of species. This problem can be solved by following three steps.
O Write the molar conductance of each species in terms of sum of their constituent ions.
(ii) Now operate the equation of each option given above by using information provided
in the question
(iii) At last if the sum of molar conductivity remaining constituent ions is equal to the molar
conductivity of species asked (here Amin.) then that will be the correct choice.
12
955 topp ( E )
Q туре your question
( C u(s) )
( boldsymbol{E}_{text {cll }}^{o}=mathbf{1 . 1 0} boldsymbol{V} )
( boldsymbol{X}-boldsymbol{a} boldsymbol{x} boldsymbol{i} boldsymbol{s}: log _{10} frac{left[boldsymbol{Z} boldsymbol{n}^{2+}right]}{left[boldsymbol{C u}^{2+}right]}, quad Y- ) axis ( : boldsymbol{E}_{c e l l} )
( A )
B.
( c )
( D )
12
956 Which of the following is/are true
regarding rancidity?

This question has multiple correct options
A. On keeping for long time, the oxidation of oils and fats, changes the taste and odour of food.
B. To prevent rancidity, food is stored in air tight containers.
C. Rancidity can also be prevented by addition of antioxidants.
D. To prevent rancidity, packed food items are flushed with an inert gas like nitrogen.

12
957 ( mathrm{Zn}(s)left|mathrm{ZnCl}_{2}(mathrm{aq})right| mathrm{Cl}^{-}(mathrm{aq})left|mathrm{Cl}_{2}(g)right| mathrm{C}(s) )
According to the above cell diagram the electrochemical cell described, the
reaction at anode is :
A ( cdot z n rightarrow z n^{2+}+2 e^{-} )
B. ( z n^{2+}+2 e^{-} rightarrow ) Zn
c. ( mathrm{cl}_{2}+2 mathrm{e}^{-} rightarrow 2 mathrm{Cl}^{-} )
D . 2CI- ( rightarrow mathrm{Cl}_{2}+2 mathrm{e}^{-} )
E. ( z n+C l_{2} rightarrow Z n C l_{2} )
12
958 Maintenance-free batteries, now in use, in
place of common batteries, have :
A. Electrodes made of lead-lead oxide
B. Electrodes made of calcium-containing lead alloy
C. Non-aqueous solvents as medium
D. Platinum electrodes
12
959 The standard reduction potential of
( E_{B i^{3+} / B i}^{o} ) and ( E_{C u^{2+} / C u}^{o} ) are ( 0.226 mathrm{V} ) and
( 0.344 mathrm{V} ) respectively. A mixture of salts of Bi and Cu at unit concentration each
is electrolysed at ( 25^{circ} mathrm{C} ). To what value
( operatorname{can}left[C u^{2+}right] ) be brought down before bismuth starts to deposit during electrolysis?
В. ( 10^{-3} M )
c. ( 10^{-5} M )
D. ( 10^{-2} M )
E ( cdot 10^{-6} M )
F. ( 10^{-1} M )
G. ( 10^{-7} M )
12
960 In the process of electroplating, ( boldsymbol{m} boldsymbol{g} ) of silver is deposited when 4 ampere of
current flows for 2 minutes. The amount
(in ( g ) ) of silver deposited by 6 ampere of current flowing for 40 seconds will be:
A. ( 4 m )
в. ( frac{m}{2} )
c. ( frac{4 m}{3} )
D. ( 3 m )
12
961 Cell equation ( : boldsymbol{A}+mathbf{2} boldsymbol{B}^{+} rightarrow boldsymbol{A}^{2+}+mathbf{2} boldsymbol{B} )
( boldsymbol{A}^{2+}+boldsymbol{2} boldsymbol{e} rightarrow boldsymbol{A} boldsymbol{E}^{circ}=+mathbf{0 . 3 4} boldsymbol{V} )
and ( log _{10} K=15.6 ) at ( 300 K ) for cell reactions
Find ( boldsymbol{E}^{circ} ) for ( boldsymbol{B}^{+}+boldsymbol{e} rightarrow boldsymbol{B} )
Given ( left[frac{2.303 R T}{n F}=0.059right]_{a t 300 K} )
A . 0.80
B. 1.26
c. -0.54
D. +0.94
12
962 Assume that impure copper contains only ( F e, A u ) and ( A g ) as impurities. After
passage of 140 ampere for 482.5 sec
the mass of anode decreased by 22.260 ( g ) and the cathode increased in mass by 22.011 g. Calculate the percentage of iron and percentage of copper originally present
A. ( F e=3 % C u=93 % )
в. ( F e=2.5 % C u=89 % )
c. ( F e=3.5 % C u=93 % )
D. None of these
12
963 How many Faradays of electricity are required to deposit 10 g of calcium from molten calcium chloride using inert
electrodes? (molar mass of calcium =
( left.40 text { g } m o l^{-1}right) )
A . ( 0.5 mathrm{F} )
B. 1
c. ( 0.25 mathrm{F} )
D. 2
12
964 The cell
( boldsymbol{P t}left(boldsymbol{H}_{2}right)(boldsymbol{1} boldsymbol{a} boldsymbol{t m}) mid boldsymbol{H}^{+}(boldsymbol{p} boldsymbol{H}=?), boldsymbol{I}^{-}(boldsymbol{a}= )
0. The electrode potential for the
reaction ( boldsymbol{A} boldsymbol{g} boldsymbol{l}+boldsymbol{e}^{-} rightarrow boldsymbol{A} boldsymbol{g}+boldsymbol{I}^{ominus} boldsymbol{i} boldsymbol{s}- )
0.151 volt. Calculate the ( p H ) value :-
A . 3.37
B. 5.26
( c .2 .56 )
D. 4.62
12
965 In a galvanic cell electron flow will be
from:
A. negative electrode to positive electrode
B. positive electrode to negative electrode
C. there will be no flow of electrons
D. cathode to anode in the extenal circuit
12
966 A constant current(0.5 amp) is passed
for 1 hour through (i) aqueous ( A g N O_{3} )
(ii) aqueous ( C u S O_{4} ) and (iii) molten
( A l F_{3}, ) separately. The ratio of the mass of the metals deposited on the cathode
is? ( left[M_{A g}, M_{C u}, M_{A l} ) are molar masses right. of the respective metals].
A ( cdot M_{A g}: 2 M_{C u}: 3 M_{A l} )
B. ( M_{A g}: M_{C u}: M_{A l} )
( mathbf{c} cdot 6 M_{A g}: 3 M_{C u}: 2 M_{A l} )
D. ( 3 M_{A g}: 2 M_{C u}: M_{A} )
12
967 During the discharge of a lead storage battery, the density of sulphuric acid fell from 1.294 to 1.139 g ( m l^{-1} ) and sulphuric acid of the density of ( 1.294 mathrm{g} )
( m l^{-1} ) is ( 39 % ) by mass and that of the
density of 1.139 g ( m l^{-1} ) is ( 20 % ) by mass. The battery holds 3.5 litre of acid and the volume practically remained constant during the discharge. Calculate the no. of ampere hour for which the battery must have been used. The charging and discharging reactions
are:
( boldsymbol{P b}+boldsymbol{S O}_{4}^{2-} rightarrow boldsymbol{P b S O}_{4}+boldsymbol{2 e} Longrightarrow )
charging
( boldsymbol{P b O}_{2}+boldsymbol{4} boldsymbol{H}^{+}+boldsymbol{S O}_{4}^{2-}+boldsymbol{2} e rightarrow )
( P b S O_{4}+2 H_{2} O Longrightarrow ) discharging
A . ( 2.5 A )
в. ( 1.7 A )
( c .3 .2 A )
D. None of these
12
968 Faraday can be defined as:
A. the magnitude of the charge of 1 mole of electrons
B. the magnitude of the electric dipole
C. a fundamental constant of nature equal to ( 6.63 times ) ( 10^{-34} J s / )photon
D. a constant that accounts for the existence of ions in
solution
E. the assignment of charges to individual atoms
12
969 The standard electrode potential of Zinc
is ( 0.76, ) V. The potential of ( 0.1 mathrm{M} ) zinc electrode is:
( mathbf{A} cdot 0.8196 mathbf{V} )
B. 0.7895 V
c. ( 0.9484 mathrm{V} )
D. ( 0.7508 mathrm{V} )
12
970 The standard potential of the following
cell is ( 0.23 V ) at ( 15^{circ} C ) and ( 0.21 V ) at
( 25^{circ} C )
( boldsymbol{P t H}_{2}(boldsymbol{g})|boldsymbol{H} boldsymbol{C l}(boldsymbol{a q} .) | boldsymbol{A} boldsymbol{g} C l(s)| boldsymbol{A} boldsymbol{g}(s) )
(i) Write cell reaction.
(ii) Calculate ( triangle H^{circ} ) and ( triangle S^{circ} ) for the cell
reaction by assuming that these quantities remain unchanged in the range ( 15^{circ} mathrm{C} ) to ( 35^{circ} mathrm{C} )
(iii) Calculate the solubility of ( A g C l ) in
water at ( 25^{circ} C . ) Given the standard
reduction potential of the ( boldsymbol{A} boldsymbol{g}^{+} / boldsymbol{A} boldsymbol{g} )
couple is 0.80 volt at ( 25^{circ} mathrm{C} )
12
971 Which one is wrong if electrolysis of ( C H_{3} C O O N a(a q) ) is made using ( P t )
electrodes?
A. ( p H ) of solution increases
B. Molar ratio of gases at anode and cathode is 3: 1
( mathrm{c} cdotleft[C H_{3} C O O^{ominus}right] ) in solution decreases
D. The molar ration of gases at anode and cathode is 2 :
1
12
972 The e.m.f of the cell obtained by combining Zn and Cu electrode of a Daniel cell with ( mathrm{N} ) calomel electrode in
two different arrangements are ( 1.083 mathrm{V} )
and ( 0.018 mathrm{V} ) respectively at ( 25^{circ} mathrm{C} ). If the standard reduction potential of ( mathrm{N} )
calomel electrode is ( 0.28 mathrm{V} ) the emf
(V) of Daniel cell is (write the
value to the nearest integer)
12
973 During the electrolysis of a concentrated brine solution. Calculate
the moles of chlorine gas produced by the passage of ( 4 F ) electricity.
12
974 In electro-chemical corrosion of metals,
the metal undergoing corrosion:
A. Becomes anode
B. Becomes cathode
c. Becomes inert
D. None is correct
12
975 A current of 9.65 amp flowing for 10 minute deposits ( 3.0 g ) of a metal. The
equivalent wt. of the metal is:
A . 10
B. 30
c. 50
D. 96.5
12
976 ( ln ) a ( H_{2}-O_{2} ) fuel cell. ( 6.72 L ) of
hydrogen at NTP reacts in 15 minutes, the average current produced in amperes is:
A. 64.3 amp
B. 643.3 amp
c. 6.43 amp
D. 0.643 amp
12
977 Given the limiting molar conductivity
as:
( A_{m}^{infty}(H C l)=126.4 Omega^{-1} c m^{2} m o l^{-1} )
( A_{m}^{infty}(N a C l)=425.9 Omega^{-1} c m^{2} m o l^{-1} )
( A_{m}^{infty}left(C H_{3} C O O N aright)= )
( 91 Omega^{-1} c m^{2} m o l^{-1} )
The molar conductivity at infinite
dilution of acetic acid
( left(i n Omega^{-1} c m^{2} m o l^{-1}right) ) will be:
( mathbf{A} cdot 481.5 )
B. 390.5
( mathbf{c} cdot 299.5 )
D . 516.9
12
978 State True or False.
In an electrochemical cell, in the inner
circuit current is carried by ions and in the external circuit, current of electrons
flows through the metal conductors.
A. True
B. False
12
979 Which of the following takes place in
discharge process at anode?
( mathbf{A} cdot P b O_{2}+4 H^{+}+S O_{4}^{2-}+2 e^{-} rightarrow P b S O_{4}+2 H_{2} O )
B ( cdot P b S O_{4}+2 H_{2} O rightarrow P b O_{2}+4 H^{+}+S O_{4}^{2-}+2 e^{-} )
( mathbf{c} cdot P b S O_{4}+2 e^{-} rightarrow P b+S O_{4}^{2} )
( mathbf{D} cdot P b S O_{4}+4 H_{2} O rightarrow P b O_{2}+8 H^{+}+S O_{4}^{2-}+2 e^{-} )
12
980 ( mathbf{A} )
0.1 M solution of a monobasic acid
has a specific resistance of ‘r’ ohm-cm. Its molar conductivity is:
A ( cdot frac{10}{r} )
в. ( 10 r )
c. ( frac{10^{4}}{r} )
D. ( frac{10^{4}}{2 r} )
12
981 Question 5. Calculate the emf of the cell in which the following
reaction takes place :
Ni(s) + 2 Ag+ (0.002 M) Ni2+ (0.160 M) + 2Ag(s)
Given that Ecell = 1.05 V
12
982 Calculate the useful work of the
reaction ( boldsymbol{A} boldsymbol{g}(boldsymbol{s})+mathbf{1} / mathbf{2} boldsymbol{C l}_{2}(boldsymbol{g}) rightarrow )
( A g C l(s) )
( operatorname{Given} boldsymbol{E}_{c_{2} / C l^{-}}^{0}=+mathbf{1 . 3 6} boldsymbol{V} )
( boldsymbol{E}_{A boldsymbol{g}|A boldsymbol{g} C l| C l^{-}}^{0}=mathbf{0 . 2 2} boldsymbol{V} ) if ( boldsymbol{P}_{C l_{2}}=mathbf{1} boldsymbol{a} boldsymbol{t m} )
and ( boldsymbol{T}=mathbf{2} mathbf{9} mathbf{8} boldsymbol{K} )
A. 110 kJ/mol
B. 220 kJ/mol
c. 55 kJ/mol
D. 1000 kJ/mol
12
983 A current of ( 1 times 10^{-5} A ) is passed
through a solution of single atom thick
layer of ( A g N O_{3} ) for 16 min ( 5 s, ) using plantinum electrodes. A uniform single atom thick layer of Ag is deposited covering ( 90 % ) of cathode surface. The
total surface area ( left(text { in } c m^{2}right) ) of cathode if
each silver atom covers an area of
( mathbf{5 . 6} times mathbf{1 0}^{-mathbf{1 6}} mathbf{c m}^{mathbf{2}} mathbf{i s} )
12
984 The process of zinc plating on iron sheet is known as
A. annealing
B. roasting
c. galvanization
D. smelting
12
985 Calculate the e.m.f of the cell in ( mathbf{V} )
( boldsymbol{P t}left|boldsymbol{H}_{2}right|(mathbf{1} . mathbf{0} boldsymbol{a} boldsymbol{t m}) mid boldsymbol{C H}_{3} boldsymbol{C O O H}(mathbf{0 . 1} boldsymbol{M}) )
( boldsymbol{K}_{boldsymbol{a}}left(boldsymbol{C} boldsymbol{H}_{3} boldsymbol{C O O H}right)=mathbf{1 . 8} times )
( mathbf{1 0}^{-mathbf{5}}, boldsymbol{K}_{boldsymbol{B}^{prime}}left(boldsymbol{N} boldsymbol{H}_{3}right)=mathbf{1 . 8} times mathbf{1 0}^{-mathbf{5}} . ) if the
value is ( -46 times 10^{-x}, ) then what is the
value of ( x ? )
12
986 Find the distance between (345) plane is a cubic batteries of length ( 7-7 A ) 12
987 What is the reduction electrode potential (in volts) of copper electrode when ( left[C u^{2+}right. )
( =0.01 mathrm{M} ) in a solution at ( 25^{0} mathrm{C} ) ?
(EO of ( left.C u^{2+} / C u text { electrode is }+0.34right) )
A . 0.399
B. 0.2809
c. 0.3105
D. 0.3695
12
988 In an experimental set-up for the measurement of emf of a half-cell using a reference electrode and a salt bridge, when the salt bridge is removed, the voltage:
A. does not change
B. increases to maximum
c. decreases half the value
D. drops to zero
12
989 The limiting molar conductivity and molar conductivity of acetic acid are
( 390.5 s . c m^{2} . m o l^{-1} ) and
( 48.15 s . c m^{2} . m o l^{-1} ) respectively
Calculate the degree of dissociation of the weak acid?
( mathbf{A} cdot 1.233 )
B. 12.33
c. 0.1233
D. 0.01233
12
990 Which of the following, when dissolved in distilled water, makes it a
good conductor?
A. Potassium iodide
B. common salt
c. Potassium dichromate
D. All of the above
12
991 Arrange the following metals in the order in which they displace each other from the solution of their salts.
( A l, C u, F e, M g ) and ( Z n )
12
992 The resistance of a decinormal solution
of an electrolyte in a conductivity cell was found to be 245 ohms Calculate the
equivalent conductivity of the solutions.
12
993 Calculate the potential of hydrogen electrode in contact with a solution of
( 5 times 10^{-3} M ) of ( B a(O H)_{2} ) at 1 atm
pressure and ( 298 mathrm{K} ) temperature:
A . – ( 0.059 v )
B. 0.059v
c. ( 0.59 v )
D – -0.59V
12
994 In a galvanic cell, the salt bridge:
A. does not participate chemically in the cell reaction
B. stops the diffusion of ions from one electrode to another
C. is necessary for the occurrence of the cell reaction
D. ensures mixing of the two electrolytic solutions
12
995 At ( 25^{circ} C, Delta H_{f}left(H_{2} O, Iright)= )
( -56700 J / ) mol and energy of
ionization of ( boldsymbol{H}_{2} boldsymbol{O}(boldsymbol{I})=mathbf{1 9 0 5 0} boldsymbol{J} / )moll
the reversible EMF at ( 25^{circ} mathrm{C} ) of the cell is
( 414 times 10^{-x}, ) then the value of ( x ) is ( ? )
( boldsymbol{P t}left|boldsymbol{H}_{2}(boldsymbol{g})(boldsymbol{1} boldsymbol{a} boldsymbol{t m})right| boldsymbol{H}^{+} | boldsymbol{O} boldsymbol{H}^{-} mid boldsymbol{O}_{2}(boldsymbol{g})(boldsymbol{1} )
if at ( 26^{circ} mathrm{C} ) the emf increase by 0.001158
( mathbf{V} )
Ans in ( mathrm{V} )
12
996 Chemically, rust is ( mathrm{Fe}_{2} mathrm{O}_{3} cdot mathrm{XH}_{2} mathrm{O} )
If true enter 1 , else enter 0 .
12
997 Which of the following which has the
highest molar conductivity?
( mathbf{A} cdotleft[C oleft(N H_{3}right)_{5} C lright] B r )
в. ( left[C oleft(N H_{3}right)_{5} C lright] S O_{4} )
( mathbf{c} cdotleft[operatorname{Co}left(N H_{3}right)_{5} C lright] N O_{2} )
D. ( left[operatorname{Co}left(N H_{3}right)_{4} C lright] cdot 2 H_{2} O )
12
998 During an electrochemical process,
A. Gibbs free energy increases
B. Gibbs free energy remain constant
C. No prediction can be made about Gibbs free energy
D. Gibbs free energy of decreases
12
999 The redox potential of ( boldsymbol{F e}^{mathbf{3}+} mid boldsymbol{F e}^{mathbf{2}+} )
electrode at ( mathrm{pH}=4 ) is:
A. ( 0.8 mathrm{v} )
B. 0.5
c. ( 0.2 v )
D. 0.1
12
1000 If aq. NaCl is electrolysed using graphite as anode and Hg as cathode than products are:
A. ( C l_{2} ) gas at anode and Na at cathode
B. ( C l_{2} ) gas at anode and ( H_{2} ) gas at cathode
c. ( O_{2} ) gas at anode and ( H_{2} ) gas at cathode
D. ( C l_{2} ) gas at anode and ( O_{2} ) gas at cathode
12
1001 Question 3.
Under what condition is E cell = 0 or A, G = 0?
:1:
1
1
12
1002 Match the List-I with List-II and List-III:
List – I
(Ouantity) List – II
(Symbol) (Quantity)
(a) Conductivity
( (p) )
( wedge_{m} )
( (b) )
Cell
constant
( (q) )
( K )
(c) Molar
conductance ( quad(mathrm{r}) quad wedge_{e} )
(d) Equivalent
conductance ( quad(mathrm{s}) )
( mathbf{A} cdot(a-q, u),(b-s, v),(c-d, w),(d-r, x) )
B . ( (a-q, u),(b-s, v),(c-p, w),(d-r, x) )
C ( .(a-b, u),(b-s, v),(c-p, w),(d-r, x) )
D . ( (a-p, u),(b-s, v),(c-p, w),(d-r, x) )
12
1003 What happens when
An iron rod is placed in ( C u S O_{4} )
solution?
12
1004 Galvanization is applying a coating of
A ( . C r )
в. ( C u )
( c cdot Z n )
D. ( P b )
12
1005 Why do we apply paint on iron articles? 12
1006 In LEDs, the longer lead is connected to and the shorter lead is connected
to
A. negative terminal; positive terminal
B. positive terminal; negative terminal
c. negative terminal; neutral terminal
D. positive terminal; neutral terminal
12
1007 What is a voltaic cell?
( A cdot A ) cell in which a spontaneous redox reaction produces electricity
B. A cell in which an oxidation reaction produces electricity.
C . A cell that produces voltage.
D. A cell full of volts.
E. Any cell that undergoes a spontaneous reaction.
12
1008 Draw a neat labelled diagram of ( boldsymbol{H}_{2}- )
( O_{2} ) fuel cell. Write the reaction occurs at
cathode of the cell.
12
1009 Q. 28 Can absolute electrode potential of an electrode be measured ?
murod
This is due
12
1010 Hiu Question 16. Which reference electrode is used to measure the
11 electrode potential of other electrodes?
12
1011 Grills of doors and windows are
always painted before they are used :
A. To look beautiful
B. To avoid corroison
c. To protect from rain
D. None of these
12
1012 The redox reaction involving the reducing power of hydrogen sulphide is:
[
begin{array}{c}
boldsymbol{S}+mathbf{2} boldsymbol{H}^{+}+mathbf{2} boldsymbol{e}^{-} rightarrow \
boldsymbol{H}_{2} boldsymbol{S}, quad boldsymbol{E}_{boldsymbol{S} / boldsymbol{H}_{2} boldsymbol{S}}^{circ}=+mathbf{0 . 1 4} boldsymbol{V}
end{array}
]
Two other half equations are:
[
boldsymbol{F} e^{3+}+boldsymbol{e}^{-} rightarrow boldsymbol{F} boldsymbol{e}^{2+} quad boldsymbol{E}_{boldsymbol{F} e^{3+} / boldsymbol{F} e^{2+}}^{mathrm{O}}=
]
[
begin{array}{l}
+mathbf{0 . 7 7} V \
B r_{2}+2 e^{-} rightarrow 2 B r^{-} quad E_{B r_{2} / B r^{-}}^{0}=
end{array}
]
( mathbf{1 . 0 7} V )
Under standard conditions, hydrogen sulphide reacts with iron ( (I I I) ) ions If this statement is true enter 1 , else
enter 0
12
1013 Which of the following forms vortex
ring?
A ( cdot P_{2} O_{5} )
в. ( P H_{3} )
c. ( N H_{3} )
D. None of the above
12
1014 Question 6. Depict the galvanic cell in which the cell reaction is
Cu+ 2Ag 2Ag + Cu2+
12
1015 An electrolytic cell is constructed for preparing hydrogen. For an average current of 1 ampere in the circuit, the time required to produced ( 450 m L ) of
hydrogen at NTP is approximately.
A. 30 min
B. 1 hour
c. 2 hours
D. 5 hours
12
1016 The electric charge for electrode deposition of one gram equivalent of a substance is:
A ( cdot 1 ) ampere ( s^{-1} )
B. 96500 coulomb ( s^{-1} )
c. 1 ampere hour ( ^{-1} )
D. 1 coulomb ( s^{-1} )
12
1017 The Gibbs energy for the decomposition
of ( A l_{2} O_{3} ) at ( 500^{circ} C ) is as follows:
( frac{2}{3} A l_{2} O_{3} rightarrow frac{4}{3} A l+O_{2} ; triangle_{r} G= )
( +966 k J m o l^{-1} )
The potential difference needed for the
electrolytic reduction of ( A l_{2} O_{3} ) at ( 500^{circ} )
is at least.
( mathbf{A} cdot 2.5 V )
в. ( 5.0 mathrm{V} )
c. ( 4.5 V )
D. 3.0 ( V )
12
1018 The two half-cell reactions of an
electrochemical cell is given as
( boldsymbol{A} boldsymbol{g}^{+}+boldsymbol{e}^{-} longrightarrow boldsymbol{A} boldsymbol{g} ; boldsymbol{E}_{boldsymbol{A} boldsymbol{g}^{+} mid boldsymbol{A} boldsymbol{g}}= )
( -0.3995 V )
( boldsymbol{F} boldsymbol{e}^{2+} longrightarrow boldsymbol{F} boldsymbol{e}^{boldsymbol{3}+}+boldsymbol{e}^{-} ; boldsymbol{E}_{boldsymbol{F} e^{3+} mid boldsymbol{F} e^{2+}}= )
( -0.7120 V )
The value of cell EMF will be:
A. ( -0.3125 V )
B. ( 0.3125 V )
c. ( 1.114 V )
D. ( -1.114 V )
12
1019 If ( 0.5 L ) of ( 0.6 M S n S O_{4} ) solution is
electrolysed for a period somin using a
current of
12
1020 a) Define Kohlrausch’s law of
independent migration of ions. Give its
applications.
b) Describe the salient features of the
Collision theory of reaction rates of bimolecular reactions.
12
1021 If ( 0.01 M ) solution of an electrolyte has a
resistance of 40 ohms in a cell having a cell constant ( 0.4 mathrm{cm}^{-1} ) then its molar
conductance would be:
A ( cdot 10^{4} )
B . ( 10^{3} )
( c cdot 10^{2} )
D. 10
12
1022 Assertion
( boldsymbol{H}_{2}+boldsymbol{O}_{2} ) fuel cell gives a constant
voltage throughout its life.
Reason
In this fuel cell, ( H_{2} ) reacts with ( O H^{-} ) ions, yet the overall concentration of
( O H^{-} ) ions does not change
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
1023 For the given data
( boldsymbol{A}+boldsymbol{B} rightleftharpoons boldsymbol{C}+boldsymbol{D} ; boldsymbol{E}^{o}=boldsymbol{a} boldsymbol{v} boldsymbol{o l} boldsymbol{t} ; boldsymbol{K}_{c}=boldsymbol{K}_{1} )
( mathbf{2} boldsymbol{A}+mathbf{2} boldsymbol{B} rightleftharpoons mathbf{2} boldsymbol{C}+mathbf{2} boldsymbol{D} ; boldsymbol{E}^{boldsymbol{o}}= )
( boldsymbol{b} boldsymbol{v} boldsymbol{o l} boldsymbol{t} ; boldsymbol{K}_{c}=boldsymbol{K}_{2} )
Select the correct choices:
This question has multiple correct options
( mathbf{A} cdot a=b )
В. ( K_{2}=K_{1}^{2} )
( mathbf{c} cdot a neq b )
( mathbf{D} cdot b=a^{2} )
12
1024 Galvanisation is a method of protecting iron from rusting, by coating with a thin layer of:
A . galliummmmmmmmmmmaliuunmmmmmm
B. aluminium
c. zinc
D. silver
12
1025 Following reactions are taking place in
a Galvanic cell, ( Z n rightarrow Z n^{2+}+ )
( mathbf{2} e^{-} ; boldsymbol{A} boldsymbol{g}^{+}+boldsymbol{e}^{-} rightarrow boldsymbol{A} boldsymbol{g} )
Which of the given representations is the correct method of depicting the
cell?
A ( cdot Z n_{(s)}left|Z n_{(a q)}^{2+}right|left|A g_{(a q)}^{+}right| A g_{(s)} )
B . ( Z n^{2+}|Z n | A g| A g^{+} )
c. ( Z n_{(a q)}left|Z n_{(s)}^{2+}right|left|A g_{(s)}^{+}right| A g_{(a q)} )
D. ( Z n_{(s)}left|A g_{(a q)}^{+}right|left|Z n_{(a q)}^{2+}right| A g_{s s} )
12
1026 Consider the following cell:
[
begin{array}{c}
boldsymbol{P t}, boldsymbol{H}_{2}(boldsymbol{g}) mid boldsymbol{2} boldsymbol{M} boldsymbol{C H}_{3} boldsymbol{C O O N H}_{4}(boldsymbol{a} boldsymbol{q}) | mathbf{2} boldsymbol{n} \
20
end{array}
]
( a+m )
0.2 atm
Given, ( boldsymbol{p} boldsymbol{K}_{boldsymbol{a}} boldsymbol{o} boldsymbol{f} boldsymbol{C H}_{3} boldsymbol{C O O H}= )
4.74 and ( p K_{b} ) of ( N H_{4} ) OHis4.74.
If ( E ) is e.m.f. of the cell in volt, then the value of ( 1000 mathrm{E} ) is ( left[text { Take } frac{2.303 R T}{F}=right. ) 0.059]( (text { e.g. }, text { if the value is } 56, ) then write
answer as ( 6) )
12
1027 Molten ( A l C l_{3} ) is electrolysed with a
current of 0.5 ampere to produce 27 g
Al. How many g-atom of ( A l ) are formed?
12
1028 What is corrosion? 12
1029 The specific conductivity of ( 0.1 mathrm{N} ) KCl solution is 0.0129 ohm ( ^{-1} mathrm{cm}^{-1} ). The
resistance of the solution in the cell is
100 ( Omega ). The cell constant of the cell will
be
A . 1.10
B. 1.29
c. 0.56
D. 2.80
12
1030 W
WUMU U U CICUUUiyul cell
ons of electrolytes is not correct?
Q. 7 Which of the statements about solutions of electroly
(a) Conductivity of solution depends upon size of ions
(b) Conductivity depends upon viscosity of solution
(c) Conductivity does not depend upon solvation of ions present
(d) Conductivity of solution increases with temperature
on of ions present in solution
conductivit
12
1031 The conductivity of saturated solution
of ( A g C l ) is found to be ( 1.86 times ) ( 10^{-6} ) ohm ( ^{-1} c m^{-1} ) and that of water is
( 6 times 10^{-8} o h m^{-1} c m^{-1} . ) If ( lambda^{0} A g C l ) is 138
( o h m^{-1} c m^{2} e q^{-1} ) the solubility product
of ( A g C l ) is:
A ( cdot 1.3 times 10^{-5} )
В. ( 1.69 times 10^{-10} )
C ( .2 times 10^{-10} )
D. ( 2.7 times 10^{-10} )
12
1032 Write Faraday’s laws of electrolysis. 12
1033 The rusting of iron takes place as follows ( 2 H^{+}+2 e+frac{1}{2} O_{2} rightarrow H_{2} O(l) ; E^{o}= )
( +1.23 V )
( F e^{2+}+2 e rightarrow F e(s) ; E^{o}=-0.44 V )
( Delta G^{o} ) for the net process is:
В. ( -161 k J ) mol ( ^{-1} )
C. -152 kJ ( m o l^{-1} )
D. ( -76 k J ) mol( ^{-1} )
12
1034 When 96500 coulombs of electricity are passed through nickel sulphate solution, the amount of nicke
deposited will be:
A . 1 mol
( c .0 .1 mathrm{mol} )
D. 2 mol
12
1035 A constant electric current flows for 4
hours through two electrolytic cells connected in series. One contains
( mathrm{AgNO}_{3} ) solution and second contains
( mathrm{CuCl}_{2} ) solution. During this time 4 grams of Ag are deposited in the first cell.
(a) How many grams of Cu are deposited in the second cell?
(b) What is the current flowing in amperes?
12
1036 Which step(s) in glycolysis require the input of energy?
A. The glucose priming step
B. The phosphorylation of glucose
c. The phosphorylation of fructose 6-phosphate
D. All of these steps require the input of energy
12
1037 Draw a labelled diagram of ‘Standard Hydrogen Electrode’. 12
1038 For ( 2 A g^{+}+C_{6} H_{12} O_{6}+H_{2} O rightarrow )
( mathbf{2} boldsymbol{A} boldsymbol{g}(boldsymbol{s})+boldsymbol{C}_{boldsymbol{6}} boldsymbol{H}_{mathbf{1 2}} boldsymbol{O}_{boldsymbol{7}}+boldsymbol{2} boldsymbol{H}^{+}, ) In K of the
change is:
( mathbf{A} cdot 66.13 )
B. 58.38
c. 28.30
D. 46.29
12
1039 calculate ( Delta G_{f}^{ominus} ) of the reaction:
( boldsymbol{A} boldsymbol{g}^{oplus}(boldsymbol{a} boldsymbol{q})+boldsymbol{C l}^{ominus}(boldsymbol{a} boldsymbol{q}) rightarrow boldsymbol{A} boldsymbol{g} boldsymbol{C l}(boldsymbol{s}) )
Given ( : Delta G^{ominus_{A g C l}}=-109 k J m o l^{-1} )
( Delta G_{left(C l^{ominus}right)}^{ominus}=-129 k J m o l^{-1} )
( Delta G_{left(A g^{oplus)}right.}^{ominus}=-77 k J m o l^{-1} )
в. ( -57 k J ) mol( ^{-} )
c. ( 57 k J ) mol ( ^{-1} )
D. ( 97 k J ) mol ( ^{-1} )
12
1040 The reduction potential of hydrogen electrode at ( p H=10 ) is:
A ( .-0.059 mathrm{V} )
B. -0.59
c. ( 0.59 v )
D. ( 0.0 mathrm{V} )
12
1041 Draw a neat and labelled diagram of
lead storage battery.
12
1042 Classify the following substances under
three headings.
Strong electrolytes, Weak electrolytes
12
1043 The negative Zn pole of Daniel cell,
sending a constant current through a circuit, decreases in mass by 0.13 g in 30 minutes. If the chemical equivalent of Zn and Cu and 32.5 and 31.5 respectively, the increase in the mass of the positive Cu pole in this time is :
A. 0.180 g
B. 0.141g
c. ( 0.126 mathrm{g} )
D. 0.242
12
1044 In the atmosphere of industrial smog, copper corrodes to form:
This question has multiple correct options
A. Basic copper carbonate
B. Copper sulphide
c. Basic copper sulphate
D. copper oxide
12
1045 When ammonia is added to the
solution, ( p H ) is raised to ( 11 . ) Which half-
cell reaction is affected by ( p H ) and by
how much?
( mathbf{A} cdot mathrm{E}_{mathrm{oxd}} ) will increase by a factor of 0.65 from ( mathrm{E}_{text {oxd }}^{circ} ) are
B. ( mathrm{E}_{text {oxd }} ) will decrease by a factor of 0.65 from ( mathrm{E}_{text {oxd }}^{circ} )
C ( cdot mathrm{E}_{text {red }} ) will increase by a factor of 0.65 from ( mathrm{E}_{text {red }}^{circ} )
D. ( mathrm{E}_{text {red }} ) will decrease by a factor of 0.65 from ( mathrm{E}^{circ} ) red
12
1046 Which of the following electrolytic solutions has the least specific
conductance?
A. ( 0.02 N )
n
B. ( 0.2 N )
( c cdot 2 N )
D. ( 0.002 N )
12
1047 The process of coating of zinc over iron
is known as
A. Calcination
B. Metallurgy
c. Tinning
D. Galvanisation
12
1048 Some of the batteries have alkaline
electrolytes-
¡) Nickel – cadmium
ii) Mercury battery
iii) Modified Leclanche cell
Cell potential is independent of ( left[mathrm{OH}^{-}right] ) in :
B. ii, ii
c. i, ii, iii
D. iii only
12
1049 On electrolysing ( K_{2} S O_{4} ) solution using inert electrodes, ( 1.68 L(mathrm{STP}) ) of gases was
obtained. How many moles of ( M n O_{4}^{-} ) could be reduced to ( M n^{2+} ) by the same
quantity of electricity?
A . 0.10
B. 0.20
c. 0.15
D. 0.02
12
1050 For the circuit shown in the adjoining figure, match the entries of column
with the entries of column II
12
1051 The specific conductance of a saturated solution of ( A g C l ) at ( 298 mathrm{K} ) is found to be
( 1.386 times 10^{-6} mathrm{Scm}^{-1} . ) Calculate its
solubility. ( left(lambda_{A g^{+}}^{circ}=62.0 S c m^{2} m o l^{-1} text {and } lambda_{C l^{-}}^{circ}=7right. )
12
1052 Define Reference electrode. 12
1053 Calculate EMF of ( left.Z nright|_{(0.01 M)} ^{Z n^{2+}} |_{(0.1 M)}^{A g^{+}} mid A g )
( E_{Z n / Z n^{+2}}^{0}=0.762 V E_{A g^{+} / A g}^{0}=+0.80 V )
A. ( 1.56 v )
B. 2.36V
c. ( 0.236 v )
D. 0.118v
12
1054 Which molecule electrolysis
temperature is maximum?
( mathbf{A} cdot A s H_{3} )
B . ( N H_{3} )
( mathbf{c} cdot P H_{3} )
( mathbf{D} cdot S b H_{3} )
12
1055 If ( 9 g m H_{2} O ) is electrolysed completely with the current of ( 50 % ) efficiency then :
A. 96500 charge is required
B. ( 2 times 96500 C ) charge is required
c. ( 5.6 L ) of ( O_{2} ) at STP will be formed
D. ( 11.2 L ) of ( O_{2} ) at STP will be formed
12
1056 In the diagram above, what is the half
reaction that occurs at the cathode?
A ( cdot A l rightarrow A l^{3+}+3 e^{-} )
B. ( N i^{2+}+2 e^{-} rightarrow N i )
( mathbf{C} cdot N i rightarrow N i^{2+}+2 e^{-} )
( mathbf{D} cdot 2 A l^{3+}+6 e^{-} rightarrow 2 A l )
E. None of these
12
1057 What will be the emf of a cell of two
hydrogen electrodes, if a negative
electrode is in contact with ( 10^{-8} M H^{+} )
ion positive electrode is in contact with
( mathbf{0 . 0 2 5 M} boldsymbol{H}^{+} mathbf{?} )
A. ( -0.18 V )
в. ( -0.28 V )
c. ( -0.38 V )
D. – ( 0.48 V )
12
1058 Q. 14 The cell constant of a conductivity cell ………
(a) changes with change of electrolyte
(b) changes with change of concentration of electrolyte
(c) changes with temperature of electrolyte
(d) remains constant for a cell
12
1059 Column II gives name of material use for device given in column I: 12
1060 Given standard ( E^{ominus}: )
( F e^{3+}+3 e^{-} rightarrow F e ; E^{ominus}=-0.036 V )
( F e^{2+}+2 e^{-} rightarrow F e ; E^{ominus}=-0.440 V )
The ( E^{ominus} ) of ( F e^{3+}+e^{-} rightarrow F e^{2+} ) is:
A. ( 0.476 V )
( V )
в. ( 0.404 V )
c. ( 0.604 V )
D. ( 0.772 V )
12
1061 Grills of doors and windows are always
painted before they are used? Give
reason
12
1062 Assertion
To protect iron from rusting it is coated
with a thin layer of zinc.
Reason
The zinc forms a barrier against
corrosion in that the steel underneath
does not come into contact with water
moisture in the air
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
1063 Stand electrode potential are; ( boldsymbol{F e}^{+2} / mathrm{Fe} quad mathrm{E}=0.44 )
( boldsymbol{F} boldsymbol{e}^{+boldsymbol{3}} / boldsymbol{F} boldsymbol{e}^{+mathbf{2}} quad mathbf{E}=mathbf{0 . 7 7} )
If ( F e^{+2}, F e^{+3} ) and ( mathrm{Fe} ) block re kept
together, then:
A ( cdot F e^{+3} ) increases
B. ( F e^{+3} ) decreases
c. ( frac{F e^{+2}}{F e^{+3}} ) reamins unchanged
D. ( F e^{+2} ) decreases
12
1064 A current of ( 3.7 mathrm{A} ) is passed for six hours between ( N i ) electrode in 0.5 litre of ( 2 M )
solution of ( N ileft(N O_{3}right)_{2} . ) The molarity of
solution at the end of electrolysis is:
12
1065 The potential of the cell containing two hydrogen electrodes as represented below, is:
( boldsymbol{P t}, boldsymbol{H}_{2(g)}left|boldsymbol{H}^{+}left(mathbf{1 0}^{-6} boldsymbol{M}right) | boldsymbol{H}^{+}left(mathbf{1 0}^{-4} boldsymbol{M}right)right| boldsymbol{H} )
( operatorname{at} 298 K )
A. ( -0.118 V )
B . ( -0.0591 V )
c. ( 0.118 V )
D. ( 0.0591 V )
12
1066 The temperature coefficient of the e.m.f. of cell, ( left(frac{d E}{d T}right)_{p} ) is given by:
A ( cdot frac{n F}{Delta S} )
в. ( frac{Delta S}{n F} )
c. ( frac{Delta S}{n F T} )
D. ( -n F E )
12
1067 Which of the following reactions does not take place during rusting?
A ( cdot H_{2} C O_{3} rightleftharpoons 2 H^{+}+C O_{3}^{2} )
B. ( 4 F e^{2+}+O_{2(d r y)} rightarrow F e_{2} O_{3} )
C. ( 4 F e^{2+}+O_{2}+4 H_{2} O rightarrow 2 F e_{2} O_{3}+8 H^{+} )
D. ( F e_{2} O_{3}+x H_{2} O rightarrow F e_{2} O_{3} cdot x H_{2} O )
12
1068 ( H_{2} S O_{4} ) solution attached to a bulb in a
beaker:
A. cannot light the bulb
B. can light the bulb
c. diffuses the bulb
D. none of above
12
1069 The standard reduction potential for ( C u^{2+} 1 C u ) is +0.34 V. The reduction
potential at ( mathrm{pH}=14 ) for the above couple is:
( boldsymbol{K}_{s p} ) of ( boldsymbol{C u}(boldsymbol{O H})_{2} ) is ( 1.0 times 10^{-19} )
( mathbf{A} cdot 0.34 V )
B . ( 0.56 V )
c. ( -0.22 V )
D. None of these
12
1070 The negative Zn pole of a Daniel cell, sending a constant current through a circuit, decreases in mass by 0.13 g in 30 minutes. If the electrochemical
equivalent of Zn and Cu are 32.5 and
31.5 respectively, the increase in the mass of the positive Cu pole in this time is:
A. 0.180 g
B. 0.141 g
c. ( 0.126 mathrm{g} )
D. 0.242
12
1071 While charging the lead storage battery
A. ( P b S O_{4} ) anode is reduced to ( P b )
B. ( P b S O_{4} ) cathode is reduced to Pb
( mathrm{c} cdot P b S O_{4} ) cathode is oxidised to ( mathrm{Pb} )
D. ( P b S O_{4} ) anode is oxidised to ( P b O_{2} )
12
1072 Question 6. The cell in which the following reaction occurs,
2 Fe3+ (aq) + 21 (aq) →→2Fe2+ (aq) + 12(s)
has E = 0.236V at 298 K, calculate the standard Gibbs energy and the
equilibrium constant of the cell reaction.
(0) Gibbs energy, 4, Gº = – OFEcell where, n is the number of electons
taking part in the reaction, so write two half reactions to find the
value of n and then calculate the standard Gibbs energy by using the
formula
AG
(1) Equilibrium constant is related to Gibbs energy as log Ko=;
2.030 RT
So, calculate K. by using this formula.
12
1073 The standard reduction potential of normal calomel electrode and reduction
potential of saturated calomel
electrodes are 0.27 and 0.33 volt
respectively. What is the concentration
of ( C l^{-} ) in saturated solution of ( K C l ? )
A . ( 0.1 M )
в. ( 0.01 M )
c. ( 0.001 M )
D. None
12
1074 Ten gram of a fairly concentrated solution of cupric sulphate is
electrolysed using 0.01 faraday of electricity. Calculate:
(i) The mass of the resulting solution.
(ii) The number of equivalents of acid or alkali in the solution.
12
1075 The molar conductivities at infinite
dilution of ( K C l, K N O_{3} ) and ( A g N O_{3} ) at
( mathbf{2 9 8} boldsymbol{K} ) are
0.01499 mho ( m^{2} m o l^{-1}, 0.01250 m h o r )
and 0.01334 mho ( m^{2} m o l^{-1} )
respectively. What is the molar
conductivity of ( A g C l ) infinite dilution at
this temperature?
12
1076 3 Faradays of electricity was passed through an aqueous solution of iron
( (I I) ) bromide. The weight (in ( g ) ) of iron metal (atomic weight ( =mathbf{5 6} ) amu) deposited at the cathode is:
A . 56
B. 84
( c cdot 112 )
D. 168
12
1077 What will be the molar conductance ‘ ( boldsymbol{Lambda} );
if resistivity is ( x ) for ( 0.1 mathrm{N} mathrm{H}_{2} mathrm{SO}_{4} ? )
A ( . quad Lambda=frac{x times 1000}{0.1} )
в. ( Lambda=frac{2 times 1000}{x times 0.1} )
c. ( _{Lambda}=frac{x times 1000}{0.5} )
D. ( _{Lambda}=frac{0.5}{1000 x} )
12
1078 When ( 4 A ) of current is passed through a ( mathbf{1} . mathbf{0} boldsymbol{L}, mathbf{0 . 1 0} boldsymbol{M} boldsymbol{F} mathbf{e}^{mathbf{3}+}(mathbf{a q}) ) solution for ( mathbf{1} boldsymbol{h} )
it is partly reduced to ( F e(s) ) and partly
of ( F e^{2+}(a q) )
Identify the correct statement(s).
This question has multiple correct options
A. 0.10 mole of electrons are required to convert all ( F e^{3+} ) to ( F e^{2} )
B. 0.025 mol of ( F e(s) ) will be deposited.
c. 0.075 mol of iron remains as ( F e^{2} )
D. 0.050 mol of iron remains as ( F e^{2} )
12
1079 The process of zinc-plating on iron sheet is known as:
A. annealing
B. roasting
c. galvanisation
D. smelting
12
1080 ( 10 g ) fairly concentrated solution of ( boldsymbol{C u} boldsymbol{S O}_{4} ) is electrolysed using ( mathbf{0 . 0 1} )
faraday of electricity. Calculate the mass of the resulting solution.
A. ( 7.6025 g )
в. ( 9.6025 g )
c. ( 6.6025 g )
D. ( 77.6025 g )
12
1081 Standard free energies of formation (in kJ/mol) at ( 298 mathrm{K} ) are -237.2,-394.4 and
-8.2 for ( boldsymbol{H}_{2} boldsymbol{O}(l), boldsymbol{C} boldsymbol{O}_{2}(boldsymbol{g}) ) and pentane ( (g) )
respectively The value of ( E_{c e l l}^{0} ) for the pentane-oxygen fuel cell is:
A ( .1 .0968 mathrm{V} )
в. ( 0.0968 V )
c. ( 1.968 V )
D. ( 2.0968 V )
12
1082 For a solution of an electrolyte at a
particular concentration and temperature, which of the following is not the function of cell constant?
1) specific conductance
2) molar conductance
3) equivalent conductance
4) conductance
A ( cdot 1,2 )
B. 1,2,3
c. 2,3,4
D. 1,4
12
1083 Three copper wires of lengths and cross sectional areas are ( (ell, boldsymbol{A}),(2 ell, boldsymbol{A} / 2) )
and ( (ell / 2,2 A) . ) Resistance is minimum in:
A. wire of cross-sectional area ( A / 2 )
B. wire of cross-sectional area A
c. wire of cross-sectional area ( 2 A )
D. same in all the three cases
12
1084 The conductance of a solution of an
electrolyte is equal to that of its specific conductance. The cell constant of the
conductivity cell is equal to
A. Resistance
B. Faraday
c. zero
D. Unity
12
1085 Why do we apply paint on iron articles? 12
1086 Which of the following reaction is used to
make a fuel cell ?
( mathbf{A} cdot 2 H_{2}(g)+O_{2}(g) rightarrow 2 H_{2} O(l) )
B. ( 2 F e(s)+O_{2}(g)+4 H^{+}(a q) rightarrow 2 F e^{2+}(a q)+2 H_{2} O(l) )
( mathbf{c} cdot P b(s)+P b O_{2}(s)+2 H_{2} S O_{4}(a q) rightarrow 2 P b S O_{4}(s)+ )
( H_{2} O(l) )
D. ( C d(s)+2 N i(O H)_{3}(s) rightarrow C d O(s)+2 N i(O H)_{2}+ )
( 2 H_{2} O(l) )
12
1087 If equal quantities of electricity are
passed through three voltmeter
containing ( boldsymbol{F} boldsymbol{e} boldsymbol{S} boldsymbol{O}_{4}, boldsymbol{F} boldsymbol{e}_{2}left(boldsymbol{S} boldsymbol{O}_{4}right)_{3} ) and
( F eleft(N O_{3}right)_{2}, ) then which of the following
is not true?
A. Amount of iron deposited in ( F e S O_{4} ) and ( F e_{2}left(S O_{4}right)_{3} ) is equal
B. Amount of iron deposited in ( F eleft(N O_{3}right)_{3} ) is ( frac{2}{3} ) of the
amount of iron deposited in ( F e S O_{4} )
C. Amount of iron deposited in ( F e_{2}left(S O_{4}right)_{3} ) and ( F eleft(N O_{3}right)_{3} ) are equal
D. Same gas will evolve in all three cases at anode
12
1088 Corrosion of metals can be prevented
when contact between metal and
is cut off.
A. nitrogen
B. hydrogen
c. oxygen
D. carbon
12
1089 Which of the following changes will
increase the EMF of the cell:
( boldsymbol{C o}(boldsymbol{s})left|boldsymbol{C o C l}_{2}left(boldsymbol{M}_{1}right) | boldsymbol{H} boldsymbol{C l}left(boldsymbol{M}_{2}right)right|left(boldsymbol{H}_{2}, boldsymbol{g}right) )
This question has multiple correct options
A. Increase the volume of ( C o C l_{2} ) solution from ( 100 mathrm{mL} ) to
200 mL.
B. Increase ( M_{2} ) from 0.01 M to 0.50 M.
C. Increase the pressure of the ( H_{2}(g) ) from 1.0 to 2.0 atm.
D. Increase ( M_{1} ) from 0.01 M to 0.50 ( mathrm{M} )
12
1090 Question 8. What is electrode potential? 12
1091 Molar conductivity of 0.15 M solution of KCl at ( 298 mathrm{K} ), if its conductivity is ( 0.0152 mathrm{S} mathrm{cm}^{-1} ) will be:
A ( cdot 124 Omega^{-1} mathrm{cm}^{2} mathrm{mol}^{-} )
B. ( 204 Omega^{-1} mathrm{cm}^{2} mathrm{mol}^{-} )
c. ( 101 Omega^{-1} mathrm{cm}^{2} ) mol ( ^{-1} )
D. ( 300 Omega^{-1} mathrm{cm}^{2} ) mol ( ^{-1} )
12
1092 If ( C u ) reacts with conc. ( H_{2} S O_{4}, ) then
what reactions take place:
A ( . C u ) is oxidised to ( C u^{2} )
B. ( S O_{4}^{2-} ) is reduced to ( S O_{2} )
c. Both of the above reactions take place
D. None of the above reaction take place
12
1093 0.37 Why is alternating current used for measuring resistance of an
electrolytic solution?
12
1094 On electrolysis, water splits into
A. positively charged hydrogen ions and negatively charged oxygen ions.
B. negatively charged hydrogen ions and positively charged oxygen ions
C. hydrogen and oxygen atoms having positive and negative charges respectively.
D. hydrogen and oxygen atoms having negative and positive charges respectively.
12
1095 The process of formation of polymers
from respective monomers is called:
A. Polyacrylonitrile
B. Co-polymerization
c. Polymerization
D. None of these
12
1096 Question 7. Why does the conductivity of a solution decrease with
dilution?
@ Conductivity Number of ions per unit volume.
12
1097 The values of the limiting molar
conductivity ( left(wedge^{circ}right) ) for ( N a C l, H C l ) and NaOAc are 126.4,425.9 and
( 91.0 S mathrm{cm}^{2} ) mol ( ^{-1}, ) respectively. For
( H O A c, wedge^{circ} ) in ( S c m^{2} m o l^{-1} ) is:
A. 390.5
B . 299.5
c. 208.5
D. 217.4
12
1098 Edible oil is not allowed to stand for a
long time in an iron or tin container
Give reasons.
12
1099 Ouestion 18. Write the Nernst equation for the cell reaction in the
Daniel cell. How will the E cell be affected when concentration of Zn2+ ions
is increased?
12
1100 A silver wire dipped in ( 0.1 mathrm{M} mathrm{HCl} ) solution saturated with AgCl develops a potential -0.25V. If ( E^{0}_{A g / A g^{+}}= )
( -0.799 V, K_{S P} ) of AgCl in pure water will
be
A ( .2 .95 times 10^{-11} )
B . ( 5.30 times 10^{-11} )
c. ( 3.95 times 10^{-11} )
D. ( 1.95 times 10^{-11} )
12
1101 When 0.1 mol ( operatorname{CoCl}_{3}left(N H_{3}right)_{5} ) is treated
with excess of ( A g N O_{3}, 0.2 ) mole of
( A g C l ) are obtained. The conductivity of solution will correspond to
A. 1: 3 electrolyte
B. 1: 2 electrolyte
c. 1: 1 electrolyte
D. 3: 1 electrolyte
12
1102 Express the relation among cell constant, resistance of the solution in
the cell and conductivity of the solution. How is molar conductivity of a solution related to its conductivity?
12
1103 In a cell, the following reaction takes
place: ( boldsymbol{F} boldsymbol{e}+boldsymbol{C u} boldsymbol{S O}_{4} rightarrow boldsymbol{F} boldsymbol{e} boldsymbol{S} boldsymbol{O}_{4}+boldsymbol{C u} )
The cell can be represented as:
A ( cdot C uleft|C u S O_{4} | F eright| F e S O_{4} )
B . ( P tleft|C u S O_{4} | F e S O_{4}right| P t )
c. ( F eleft|F e S O_{4} | C u S O_{4}right| C u )
D. ( C u S O_{4}left|C u | F e S O_{4}right| F e )
12
1104 The specific conductance of saturated
solution of ( C a F_{2} ) is ( 3.86 times 10^{-5} ) ohm
( c m^{-1} ) and that of water used for
solution is ( 0.15 times 10^{-5} ). The specific
conductance of ( C a F_{2} ) alone is:
A. ( 3.71 times 10^{-5} )
В. ( 4.01 times 10^{-5} )
c. ( 3.7 times 10^{-4} )
D . ( 3.86 times 10^{-4} )
12
1105 Quinhydrone half cell is not reversible
to:
This question has multiple correct options
( mathbf{A} cdot mathbf{H}^{+} )
B. quinone
c. quinol
D. он
12
1106 Calculate the electrode potential of the
electode
( Z n / Z n^{2+}(text {conc.}=0.1 M) ) at ( 25^{circ} C )
Given that ( boldsymbol{E}_{Z n, Z n^{2+}}^{circ}=mathbf{0 . 7 6 1 8} ) volt.
12
1107 The molar conductivity of
( 0.1 M C H_{3} C O O H ) solution is
( 4 S c m^{2} m o l^{-1} . ) What is the specific
conductivity and resistivity of the solution.
12
1108 Internal resistance of a battery cell
increases with:
A. increase in concentration of electrolyte
B. increase in distance between two electrodes
C. increase in area of the plates inside the electrolyte
D. increase in size of the electrodes
12
1109 In a fuel cell the fuel is fed to which
compartment?
A. Anode compartment
B. Cathode compartment
c. Both the compartments
D. None of the above
12
1110 ( E_{C l O_{4}^{-} / C l O_{3}^{-}}^{o} ) and ( E_{C l O_{3}^{-} / C l O_{2}^{-}}^{o} operatorname{are}+0.36 V )
and ( +0.33 V ) respectively. The
equilibrium concentration of per chlorate ion for the given reaction would be:
[
begin{array}{rcc}
& mathbf{2 C l O}_{mathbf{3}}^{-} rightleftharpoons mathbf{C l O}_{mathbf{2}}^{-}+mathbf{C l O}_{mathbf{4}}^{-} \
boldsymbol{t}=mathbf{0} & mathbf{0 . 1} mathbf{M} & mathbf{0}
end{array}
]
A ( .0 .19 M )
B. 0.024
c. 0.24
D. 0.019
12
1111 As a lead storage battery is charged.
A. Lead dioxide dissolves
B. Sulphuric acid is regenerated
C. Lead electrode becomes coated with lead sulphate
D. The concentration of sulphuric acid decreases
12
1112 In an electrochemical cell, anode and
cathode are
A. Positively and negatively charges ions
B. Positively and negatively charges electrodes
C. Negatively and positively charged electrodes
D. Negatively and positively charged ions
12
1113 The specific conductance of a
( N / 10 K C I ) at ( 25^{0} C ) is
0.0112 oh ( m^{-1} c m^{-1} . ) The resistance of
cell containing solution at the same temperature was found to be 55ohms.
The cell constant will be:
A ( cdot 6.16 mathrm{cm}^{-1} )
B. ( 0.616 c m^{-1} )
c. ( 0.0616 mathrm{cm}^{-1} )
D. ( 616 mathrm{cm}^{-1} )
12
1114 Which of the following is true for an electrolytic cell?
A. An electric current causes an otherwise nonspontanteous chemical reaction to occur
B. Reduction occurs at the anode.
C. A spontaneous electrochemical reaction produces an electric current
D. The electrode to which electrons flow is where oxidation occurs
E. None of the above
12
1115 Q Type your question
following apparatus was set up. Which
among the following statement(s)
is(are) correct?
(i) Bulb will not glow because electrolyte is not acidic.
(ii) Bulb will glow because NaOH is a strong base and furnishes ions for
conduction.
(iii) Bulb will not glow because circuit
is incomplete.
(iv) Bulb will not glow because it
depends upon the type of electrolytic
solution.
( A cdot ) (i) and (iii)
B. (ii) and (iv)
c. (ii) only
D. (iv) only
12
1116 VUVCHI
Q.55 Match the items of Column I and Column
items of Column I and Column II on the basis of data given
below
Ff/f = 2.871. Ex = -3.5V.
FAU3+ /Au = 1.4V, E = 1.09V
Bro/Br
Column 1
A.
1.
BLI
2.
C. Au3+
3.
D. Br
4.
E AU 5.
6
7.
Column II
Metal is the strongest reducing agent
Metal ion which is the weakest oxidising agent
Non-metal which is the best oxidising agent
Unreactive metal
Anion that can be oxidised by Au+|
Anion which is the weakest reducing agent
Metal ion which is an oxidising agent
12
1117 The reduction potential of a hydrogen electrode containing a solution of ( boldsymbol{p} boldsymbol{H}=boldsymbol{4} ) is:
A . 0.336
B. 4.059 ( v )
c. – ( 0.236 v )
D. 3.941
12
1118 Fuel cells are better than other cells.
Give any two reasons.
12
1119 The potential of a hydrogen electrode in
a solution with ( p O H=4 ) at ( 25^{circ} C ) is:
A . -0.059
B. 0.059
c. -0.59
D. 0.59
12
1120 List 1 and List 2 contains four entries
each. Entries of List 1 are to be matched
with some entries of List 2. One or more
than one entries of List 1 may have the matching with the same entries of List
2
12
1121 Which metals does not corrode easily?
A . Gold
B. Iron
c. Aluminium
D. zinc
12
1122 The current inside a copper voltameter:
A. is half the outside value
B. is the same as the outside value
C. is twice the outside value
D. depends on the concentration of ( C u S O_{4} )
12
1123 Which of the following statements
regarding fuel cell is (are) true? This question has multiple correct options
A. They have efficiency of about ( 60-70 % )
B. There efficiency is less then conventional methods
C. They do not cause pollution
D. They can supply indefinite amount of energy until outside supply of reactants is maintained
12
1124 Which is true according to the Faraday
Law of electrolysis? Here ( m ) is the mass
deposited at an electrode, ( Q ) is the
charge at the electrode and ( I ) is the
current passed.
( A cdot m propto I^{2} )
в. ( m propto Q )
( mathrm{c} cdot m propto Q^{2} )
D. ( m ) does not depend on ( Q )
12
1125 The reference electrode is made from
which of the following?
A. ( Z n C l_{2} )
в. ( mathrm{CuSO}_{4} )
c. ( H g_{2} C l_{2} )
D. ( H g C l_{2} )
12
1126 Ammonium chloride used in dry cell
acts as
A. Catalyst
B. Electrolyte
C. Polariser
D. Both (1) and (3)
12
1127 Number of coulombs required to
liberate 0.5 mol of ( boldsymbol{O}_{2} ) is:
A . 19300
B. 193000
c. 96500
D. 9650
12
1128 What happens when you join the free
ends of the tester for more than a few
minutes?
A. Cells of the battery will drain quickly.
B. The current will not be able to pass.
c. There would be no conduction of electricity
D. All of the above
12
1129 How many faradays are released when ( 12.7 g ) of copper metal is changed into copper ions? 12
1130 The term infinite dilution refers when:
A. ( alpha rightarrow 1 ), for weak electrolytes
B. an electrolyte is 100% dissociated
c. all interionic effects disappears
D. all of the above
12
1131 ( left[A u(C N)_{2}right]^{ominus} ) is a very stable
complex under certain conditions. The concentration of cyande ion which is required to keep 99 mol% of the gold in
the form of the cyanide complex is: [Given ( left.K_{f}left[A u(C N)_{2}right]^{ominus}=4 times 10^{28}right] )
A ( .2 times 10^{-28} M )
в. ( 3 times 10^{-14} M )
c. ( 5 times 10^{-28} M )
D. ( 5 times 10^{-14} M )
12
1132 The standard reduction potential ( E^{circ} ) for half reaction are:
( Z n rightarrow Z n^{2+}+2 e^{-} ; E^{o}=+0.76 V )
( boldsymbol{F e} rightarrow boldsymbol{F} boldsymbol{e}^{2+}+boldsymbol{2} boldsymbol{e}^{-} ; boldsymbol{E}^{o}=+boldsymbol{0 . 4 1} boldsymbol{V} )
The EMF of the cell reaction is:
( boldsymbol{F} boldsymbol{e}^{2+}+boldsymbol{Z} boldsymbol{n} rightarrow boldsymbol{Z} boldsymbol{n}^{2+}+boldsymbol{F} boldsymbol{e} )
A. ( -0.35 V )
в. ( +0.35 V )
( mathrm{c} cdot+1.17 V )
D. -1.17V
12
1133 ( 4.5 g ) of aluminium (At. mass ( =27 ) atm
is deposited at cathode from ( boldsymbol{A} boldsymbol{l}^{mathbf{3}+} )
solution by a certain quantity of electric charge. The volume of hydrogen
produced at STP from ( boldsymbol{H}^{+} ) ions in solution by the same quantity of electric charge will be
A . ( 44.8 L )
B. 22.4 L
c. ( 11.2 L )
D. ( 5.6 L )
12
1134 Arrange the following reducing agents in the order of increasing strength under standard state condition. Justify
the answer.
Element Al(s)
( mathrm{Cu}(mathrm{s}) quad mathrm{cl}(mathrm{aq}) )
( E^{o} quad v^{-1.66} ) ( 1.36 mathrm{v} ) ( 0.34 mathrm{V} )
12
1135 Consider the following equation for a
cell
( boldsymbol{A}+boldsymbol{B} rightleftharpoons boldsymbol{C}+boldsymbol{D} )
( boldsymbol{E}^{o}= )
( boldsymbol{X} boldsymbol{v o l t}, quad boldsymbol{K}_{e q}=boldsymbol{K}_{1} )
( mathbf{2 A}+mathbf{2 B} rightleftharpoons mathbf{2 C}+mathbf{2 D} ; quad boldsymbol{E}^{boldsymbol{o}}= )
( boldsymbol{y} ) volt, ( quad boldsymbol{K}_{e q}=boldsymbol{k}_{2} )
A. ( X=y, K_{1}=K_{2} )
B . ( X=2 y, K_{1}^{2}=K_{2} )
C . ( X=y, K_{1}^{2}=K_{2} )
D. ( X^{2}=y, K_{1}^{2}=K_{2} )
12
1136 Statement ( 1: ln ) an electrolytic cell, the anode becomes positive and the cathode becomes negative.
Statement 2: Anions migrate to the anode and cations migrate to the
cathode.
A. Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation of Statement 1
B. Both the Statement 1 and Statement 2 are correct, but Statement 2 is NOT the correct explanation of Statement 1.
c. Statement 1 is correct, but Statement 2 is not correct
D. Statement 1 is not correct, but Statement 2 is correct
12
1137 Number of Faraday required to get ( 1 g )
atom of ( M g ) from ( M g C l_{2} ) is:
A. ( 0.0035 F )
в. ( 2 F )
( c .1 F )
D. ( 0.2 F )
12
1138 The cell in which the following reaction
occurs:
( 2 F e^{3+}(a q)+2 I^{-}(a q) rightarrow 2 F e^{2+}(a q)+ )
( boldsymbol{I}_{2}(boldsymbol{s}) )
has ( E_{c e l l}^{circ}=0.236 V ) at ( 298 K . ) Calculate
the standard Gibbs energy of the cell
reaction. (Given : ( 1 boldsymbol{F}= )
( left.mathbf{9 6}, mathbf{5 0 0} boldsymbol{C} boldsymbol{m o l}^{-mathbf{1}}right) )
12
1139 Give Nernst equation:
Calculate the electrode potential of the
following single electrode. ( boldsymbol{C u}_{(a q)}^{++}(boldsymbol{C}=mathbf{0 . 0 1 M}) / boldsymbol{C u} ;left(boldsymbol{E}^{circ}=right. )
( +0.337 V) )
12
1140 The pH of solution in a cell : Reference
electrode ( | boldsymbol{H}_{3} boldsymbol{O}^{+}(?) boldsymbol{H}_{2} mid boldsymbol{P} boldsymbol{t} ) can be
determined by using the formula ( boldsymbol{p} boldsymbol{H}= ) ( -frac{left[boldsymbol{E}_{text {cell}}+boldsymbol{E}_{text {ref}}right]}{mathbf{0 . 0 5 9}} . ) However, the use of
hydrogen electrode to determine pH is usually ignored. Which are the correct facts about this observation?
This question has multiple correct options
A. The use of H-electrode hinders in the establishment of the equilibrium at the surface and the electrode no Ionger behaves reversibly
B. The use of H-electrode is usually restricted if solution contains reducible materials
c. The use of H-electrode is usually restricted as it is easily poisoned
D. The use of quinhydrone electrode as electrode is usually preferred as reference electrode ( left|H_{3} O^{+}, Q, Q H_{2}right| A u )
12
1141 The molar conductivity of a solution of a weak acid ( boldsymbol{H} boldsymbol{X}(mathbf{0 . 0 1} boldsymbol{M}) ) is ( mathbf{1 0} ) times
smaller than the molar conductivity of a
solution of a weak acid ( boldsymbol{H} boldsymbol{Y}(mathbf{0 . 1} boldsymbol{M}) . ) If
( boldsymbol{lambda}_{boldsymbol{X}^{-}}^{circ} approx boldsymbol{lambda}_{boldsymbol{Y}^{-}}^{circ}, ) the difference in their ( boldsymbol{p} boldsymbol{K}_{boldsymbol{a}} )
values, ( boldsymbol{p} boldsymbol{K}_{boldsymbol{a}}(boldsymbol{H} boldsymbol{X})-boldsymbol{p} boldsymbol{K}_{boldsymbol{a}}(boldsymbol{H} boldsymbol{Y}), ) is
(consider degree of ionization of both
acids to be ( <<1 ) )
12
1142 The reaction taking place is:
( mathbf{A} cdot H g_{2} C l_{2}(s)+2 A g(s) rightarrow 2 A g C l(s)+2 H g(l) )
B ( cdot 2 H g_{2} C l_{2}(s)+2 A g(s) rightarrow 4 A g C l(s)+2 H g(l) )
( mathbf{c} cdot H g_{2} C l_{2}(s)+3 A g(s) rightarrow A g C l(s)+2 H g(l) )
D. None of these
12
1143 Question 13. How much electricity in terms of Faraday is requir
produce.
(i) 20.0 g of Ca from molten CaCl ?
(ii) 40.0 g of Al from molten Al2O3?
12
1144 What is the electrode potential in (in ( V ) ) of the following electrode at
( mathbf{2 5}^{o} boldsymbol{C}>boldsymbol{N} boldsymbol{i}^{2+}(mathbf{0 . 1} boldsymbol{M}) mid boldsymbol{N} boldsymbol{i}(boldsymbol{s}) )
(standard reaction potential of
( left.N i^{2+} / N i text { is }-0.25 Vright) )
A . ( -0.28 v )
B. -0.34 V
c. ( -0.82 v )
D. -0.22V
12
1145 Arrange the following compounds in order of their Molar conductance:
(।) ( boldsymbol{K}left[boldsymbol{C o}left(boldsymbol{N} boldsymbol{O}_{2}right)_{4}left(boldsymbol{N} boldsymbol{H}_{3}right)_{2}right] )
( (|)left[boldsymbol{C r}(boldsymbol{O} boldsymbol{N} boldsymbol{O})_{3}left(boldsymbol{N} boldsymbol{H}_{3}right)_{3}right] )
( (||)left[boldsymbol{C r}left(boldsymbol{N} boldsymbol{H}_{3}right)_{6}right] boldsymbol{C l}_{3} )
( (mathrm{IV}) M gleft[C rleft(N O_{2}right)_{5}left(N H_{3}right)right] )
( A cdot|<I<I V<| 1 )
B. II IV ( <1<11 )
c. ( |<1=1 V<| )
D. IV <III <II<I
12
1146 A Faraday is:
A. the magnitude of the charge of 1 mole of electrons
B. the magnitude of the electric dipole
C. a fundamental constant of nature equal to ( 6.63 times ) ( 10^{-34} J s / )photon
D. a constant that accounts for the existence of ions in
solution
12
1147 The specific conductance of a solution is ( 0.3568(o h m)^{-1} mathrm{cm}^{-1} mathrm{When} ) placed in a cell
the conductance is 0.0268 oh ( m^{-1} )
The cell constant is:
A ( cdot 1.331 mathrm{cm}^{-1} )
B. ( 13.31 c m^{-1} )
( mathbf{c} cdot 0665 mathrm{cm}^{-1} )
D. ( 6.65 mathrm{cm}^{-1} )
12
1148 The efficiency of a fuel cell is given by:
A ( cdot frac{Delta s}{Delta G G} )
в. ( frac{Delta H}{Delta G} )
c. ( frac{Delta G}{Delta S G} )
D. ( frac{Delta G}{Delta H} )
12
1149 The density of copper is ( 8.94 m L^{-1} ) Find out the number of coulombs
needed to plate an area ( 10 times 10 mathrm{cm}^{2} ) to
a thickness of ( 10^{-2} mathrm{cm} ) using ( mathrm{Cu} ) SO
solution as electrolyte. (At. mass of ( boldsymbol{C u}=mathbf{6 3 . 6}) )
12
1150 Assertion
Zinc is used in the galvanization of iron.
Reason
Its coating on iron articles increases their life by protecting them from
rusting.
A. If both Assertion and Reason are correct and Reason is the correct explanation of Assertion
B. If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion
C. If Assertion is correct but Reason is incorrect
D. If Assertion is incorrect but Reason is correct
12
1151 The potential value of standard hydrogen electrode is 12
1152 When electricity is passed through a
solution of ( A l C l_{3} ) and ( 13.5 g ) of ( A l )
is deposited, the number of Faraday required must be:
A . 0.5
в. 1.0
c. 1.5
D. 2.0
12
1153 ( boldsymbol{Z} boldsymbol{n}_{(s)}left|boldsymbol{Z} boldsymbol{n}_{(boldsymbol{a q})}^{boldsymbol{2}+}(boldsymbol{1} boldsymbol{M}) | boldsymbol{N} boldsymbol{i}_{(boldsymbol{a q})}^{2+}(boldsymbol{1} boldsymbol{M})right| boldsymbol{N} boldsymbol{i}_{(s)} )
Which is incorrect for the above given
cell?
A. Electrochemical cell
B. Voltaic cell
c. Galvanic cell
D. Daniel cell
12
1154 Which one of the following species has maximum conductance in their
aqueous solutions?
A ( cdot K_{2} P t C l_{6} )
в. ( P t C l_{4} cdot 2 N H_{3} )
c. ( P t C l_{4} cdot 3 N H_{3} )
D. ( P t C l_{4} cdot 5 N H_{3} )
12
1155 If ( F e^{3+}+y^{4-} rightleftharpoons F e Y^{ominus} ; K_{f}=1.3 times )
( 10^{25} )
( F e^{3+}+Y^{4-} rightleftharpoons F e Y^{2-} ; K_{f}=2.1 times 10^{14} )
And ( F e^{3+}+e^{-} rightleftharpoons F e^{2+} ; E^{ominus}=+0.77 V )
( boldsymbol{E}^{ominus} ) for ( boldsymbol{F} boldsymbol{e} boldsymbol{Y}^{ominus}+boldsymbol{e}^{-} rightarrow boldsymbol{F} boldsymbol{e} boldsymbol{Y}^{2-} )
A . 0.13 v
B. ( 0.26 mathrm{v} )
c. ( 1.2 v )
D. 1.6
12
1156 Which of the following statements is
false?
A. Vegetables conduct electricity
B. Passage of electric current will not change the colour of a solution
C. An electrode conducts electricity
D. Electroplating is one of the applications of chemical effects of electrical current
12
1157 Maximum conductance is shown by:
A . ( 0.1 M ) NaCl
в. ( 0.1 M ) Н ( _{2} ) SO ( _{4} ),
c. ( 0.1 M ) sucrose
D. ( 0.1 M ) glucose
12
1158 Consider the cell:
( boldsymbol{P t}left|boldsymbol{H}_{2}left(boldsymbol{p}_{1} boldsymbol{a t m}right)right| boldsymbol{H}^{oplus}left(boldsymbol{x}_{1} boldsymbol{M}right) | boldsymbol{H}^{oplus}left(boldsymbol{x}_{2} boldsymbol{N}right. )
The cell reaction be spontaneous if This question has multiple correct options
( mathbf{A} cdot p_{1}=p_{2} ) and ( x_{1}>x_{2} )
B . ( p_{1}=p_{2} ) and ( x_{1}p_{2} )
D. ( x_{1}=x_{2} ) and ( p_{1}<p_{2} )
12
1159 Which of the following metals is used to prevent rusting of iron, as per electrochemical method?
( A cdot Z n )
B. Sn
c. ( mathrm{Ni} )
D. cu
12
1160 A current of ( 2.0 mathrm{A} ) is passed for 5 hours through a molten metal salt deposits 22.2 ( g ) of metal (At. mass: 177 u). The oxidation states of the metal in metal
salt is:
( A cdot+1 )
( B .+2 )
( c cdot+3 )
( D cdot+4 )
12
1161 Fuel cell involves which of the following
reaction(s)?
This question has multiple correct options
( mathbf{A} cdot O_{2}(g)+2 H_{2} O(l)+4 e^{-} rightarrow 4 O H^{-}(a q .)(text { at cathode }) )
B. ( O_{2}(g)+2 H_{2} O(l)+4 e^{-} rightarrow 4 O H^{-}(a q .) ) (at anode)
( mathbf{c} cdot 2 H_{2}(g)+4 O H^{-}(a q) rightarrow 4 H_{2} O(l)+4 e^{-}(a t text { anode }) )
D. ( 2 H_{2}(g)+4 O H^{-}(a q .) rightarrow 4 H_{2} O(l)+4 e^{-} ) (at cathode)
12
1162 When metal atoms are deposited on
the cathode:
A. the mass of the cathode and anode increases by an equal amount
B. the mass of the cathode decreases and the mass of
the anode increases by an equal amount
c. the mass of the cathode increases and the mass of the
anode decreases by an equal amount
D. the mass of the cathode increases more than the
mass of the anode that decreases
12
1163 A current of 0.965 ampere is passed through ( 500 mathrm{ml} ) of ( 0.2 mathrm{M} ) solution of
( Z n S O_{4} ) for 10 minutes. The molarity of
( Z n^{2+} ) after deposition of zinc is:
A. 0.1
B. 0.5 ( M )
c. ( 0.8 mathrm{M} )
D. 0.194 M
12
1164 State True or False.
In recharging of lead storage cell, sulphuric acid is produced.
A. True
B. False
12
1165 In electrochemical passivity:
A. thin visible oxide film is formed
B. thin invisible oxide film is formed
C. thick visible oxide film is formed
D. thick invisible oxide films formed
12
1166 In fuel cells, the reaction that takes
place at the anode is:
A ( cdot H_{2}(g)+2 O H^{-}(a q) rightarrow 2 H_{2} O(l)+2 e^{-} )
в. ( O_{2}(g)+2 H_{2} O(l)+4 e^{-} rightarrow 4 O H^{-}(a q) )
c. ( 4 O H^{-} rightarrow O_{2}+2 H_{2} O+4 e^{-} )
D. ( 2 H^{+}+2 e^{-} rightarrow H_{2} )
12
1167 The factors, which influence the
conductance of solutions:

This question has multiple correct options
A. solute-solute interaction
B. solute-solvent interaction
c. temperature
D. solvent-solvent interaction

12
1168 Faraday’s second law of electrolysis is
related to the:
A. molecular mass of the electrolyte
B. Equivalent weight of the cation /anion
C. Atomic weight of the electrolyte
D. Atomic number of the cation/anion
12
1169 Plots of ( E_{text {cell}} ) with ( log _{10} Q ) for the reaction, ( Z n(s)+C u^{2+}(a q .) rightleftharpoons )
( boldsymbol{C u}(boldsymbol{s})+boldsymbol{Z} boldsymbol{n}^{2+}(boldsymbol{a q} .) ) gives a straight
line with an intercept ( 1.10 . ) If ( boldsymbol{E}_{c e l l}= ) ( 1.1591 V ), then value of ( Q ), i.e. ( frac{left[Z n^{2+}right]}{left[C u^{2+}right]} ) is:
A . 0.01
B. ( 0 . )
c. 100
D. 10
12
1170 On heating, sodium and sulphur can be melted. Molten sodium and molten
sulphur are used?
A. For refining lead
B. As a medium for extracting metals
c. As catalysts
D. As electrodes in a modern kind of battery
12
1171 Differentiate between the terms strong electrolyte and weak electrolyte. (sating any two differences) 12
1172 A conductance cell was calibrated by
filling it with a ( 0.02 M ) solution of
potassium chloride (specific conductance ( =0.2768 ) oh ( m^{-1} m^{-1} )
and measuring the resistance at ( 298 K )
which was found to be 457.3 ohm. The
cell was then filled with a calcium
chloride solution containing ( 0.555 g ) of
( mathrm{CaCl}_{2} ) per litre. The measure
resistance was 1050 ohm. Calculate
the molar conductivity of ( C a C l_{2} )
solution.
12
1173 Given the standard potential of the
following at ( 25^{circ} mathrm{C} . M n O_{2} rightarrow M n^{3+} )
( boldsymbol{E}^{ominus}=mathbf{0 . 9 5} boldsymbol{V} )
( M n^{3+} rightarrow M n^{2+} ; E^{ominus}=1.51 V )
The standard potential of ( M n O_{2} rightarrow )
( M n^{2+} ) is :
A . ( 1.23 mathrm{v} )
B. 0.2 ( v )
c. ( 0.02 mathrm{v} )
D. None of these
12
1174 Lead storage battery is most widely used in automobiles.
A. True
B. False
12
1175 Select the correct statements about the
electrolysis
This question has multiple correct options
A. Electric current is used to drive a non spontaneous reaction
B. ( Delta G ) is positive for chemical process during electrolysis
C. Cations and anions move towards the anode in the anode and cathode respectively
D. Over voltage is generally associated with anode in the electrolysis of ( N a C l(a q) )
12
1176 In three test tubes ( P, Q, ) and ( R ) iron
nails, water, oil and anhydrous calcium
chloride is taken. Among these test
tubes, in which test tubes corrosion of
nails will not take place?
( A cdot P, Q ) and ( R )
B. ( P ) and ( R )
( c . P ) and ( Q )
D. ( Q ) and ( R )
12
1177 During the electrolysis of ( 0.1 mathrm{M} ) Cu SO solution using copper electrodes, a depletion of ( left[C u^{2+}right] ) occurs near the cathode with a corresponding excess near the anode, owing to inefficient stirring of the solution. If the concentrations of ( left[C u^{2+}right] ) near the
anode ( & ) cathode are respectively 0.12 M
& 0.08 M, calculate the back e.m.f.
developed. Temperature ( =298 mathrm{K} )
A . 22 ( mathrm{mv} )
B. 5.2 mv
c. ( 29 mathrm{mv} )
D. 59 mv
12
1178 What is the time (in sec) requried for depositing all the silver present in
( 125 m L ) of ( 1 M A g N O_{3} ) solution by
passing a current of ( 241.24 A ? ) ( (1 F=96500 text { coulombs }) )
A . 10
B. 50
c. 100
D. 90
12
1179 Reduction occurs at cathode in:
A. galvanic cell
B. electrolytic cell
C. both galvanic and electrolytic cell
D. neither galvanic nor electrolytic cell
12
1180 For the galvanic cell :
( boldsymbol{A l}(boldsymbol{s})left|boldsymbol{A} boldsymbol{l}^{3+}(boldsymbol{a} boldsymbol{q})(boldsymbol{0} cdot boldsymbol{1} boldsymbol{M})right| boldsymbol{A} boldsymbol{g}^{+}(boldsymbol{a} boldsymbol{q})(boldsymbol{0} cdot boldsymbol{1} boldsymbol{M}) )
which of the following is/are correct? This question has multiple correct options
A. Reaction quotient ( Q=1.0 times 10^{-2} )
в. ( log _{10} Q=2 )
c. ( Q=1.0 times 10^{3} )
D. ( Q=1.0 times 10^{2} )
12
1181 What is the main principle involved in
voltaic cell?
A. Conversion of chemical energy into heat energy
B. Conversion of heat energy into electrical energy
C. Conversion of chemical energy into electrical energy
D. Conversion of electrical energy into chemical energy
12
1182 Which of the following devices can be used to detect a weak current?
A. Use of electric bulb in tester
B. Use of LED in tester
c. A tester using magnetic effects of current
D. Both B and C
12
1183 If a current of 0.3 ampere is drawn from
a Daniell cell for 1 hour, what would be
the change in mass of electrodes? (At. mass of ( C u=63.5 ) and ( Z n=65.37 )
12
1184 For which of the following electrolytic
solution ( wedge_{m} ) and ( wedge_{e} ) are equal?
A. ( B a C l_{2} )
в. ( K C l )
( mathbf{c} cdot A l_{2}left(S O_{4}right) )
D. ( operatorname{CaCl}_{2} )
12
1185 No rusting takes place in absence of moisture.
A . True
B. False
12
1186 A conductivity cell filled with
( 0.01 M A g N O_{3} ) solution gives at ( 25^{circ} C )
a resistance of ( 1442 Omega ). If the molar
conductivity of ( 0.01 M A g N O_{3} ) solution is ( 124.8 Omega^{-1} c m^{2} m o l^{-1}, ) what
is the cell constant?
12
1187 For the cell Pt ( mid mathbf{H}_{2}(0.4 text { at } m) mid mathbf{H}^{+}(p H=1) ) ( left.|(p H=2) mid H_{2} 90.1 text { atm }right) mid P t . ) The
measured potential at ( 25^{circ} mathrm{C} ) is:
A . ( -0.1 V )
B. ( -0.5 V )
c. ( -0.041 V )
D. ( -0.030 V )
12
1188 Jamila started noticing some kind of reddish brown particles around a photo frame, which is an old one. Why it could have happened and what is it? 12
1189 The ionization constant of a weak acid
is ( 1.6 times 10^{-5} ) and the molar
conductivity at infinite dilution is ( 380 times 10^{-4} S m^{2} m o l^{-1} . ) If the cell
constant is ( 0.01 mathrm{m}^{-1} ) then conductance
of ( 0.01 M ) acid solution is:
A ( cdot 1.52 times 10^{-5} mathrm{S} )
в. ( 1.52 times 10^{-7} ) S
c. ( 1.52 times 10^{-3} ) S
D. ( 1.52 times 10^{-4} ) S
12
1190 Q29. Given the standard electrode potentials,
K*/K = -2.93 V, Ag/Ag = 0.80 V, Hg2+/Hg = 0.79 V, Mg2+/Mg = -2.37 V,
Cr**/Cr = -0.74 V. Arrange these metals in increasing order of their reducing power.
12
1191 The more negative the standard potential, the ( ldots ) is its ability to
displace hydrogen from acids.
A. Greater
B. Lesser
c. Negetivity of the satndard potential has nothing to do with displacement of hydrogen
D. Depends on the acid
12
1192 Assertion
The voltage of mercury cell remains
constant for longer period of time.
Reason
It is because net cell reaction does not
involve ions.
A. Both Assertion and Reason are correct and Reason is
the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
1193 Find the time required to liberate 1 litre
of ( boldsymbol{H}_{2} ) at ( mathrm{STP} ) in an electrolytic cell
operating at 5 A.
A . 19 min
B. 24 min
c. 29 min
D. 14.5 min
12
1194 3 faraday of electricity are passed through molten ( A l_{2} O_{3}, ) aqueous
solution of ( C u S O_{4} ) and molten NaCl
taken in three different electrolytic
cells. The amount of ( mathrm{Al}, mathrm{Cu}, ) and ( mathrm{Na} )
deposited at the cathodes will be in the ratio of
A. 1 mole : 2 mole : 3 mole
B. 3 mole:2 mole:1 mole
c. 1 mole : 1.5 mole : 3 mole
D. 1.5 mole : 2 mole : 3 mole
12
1195 In an electrolytic cell:
This question has multiple correct options
A. anode is positively charged
B. cathode is negatively charged
C. oxidation takes place at anode
D. reduction takes place at cathode
12
1196 Which metal pairs when coupled will get maximum emf for a voltaic cell?
( A cdot F e ) and ( C u )
B. Pb and Cu
c. Cu and Au
D. ca and cu
12
1197 Q. 6 An electrochemical cell can behave like an electrolytic cell when
(a) Ecell = 0
(b) Ecell >Eext
(c) Eext > Ecell
(d) Ecell = Eext
Dumin noll and increased reactic
12
1198 Which of the following will be most easily corroded in moist air?
A. ( Z n )
в. ( F e )
c. ( N i )
D. ( S n )
12
1199 If the values of ( wedge_{infty} ) of ( boldsymbol{N} boldsymbol{H}_{4} boldsymbol{C l}, boldsymbol{N} boldsymbol{a} boldsymbol{O H} )
and ( N a C l ) are 130,217 and
109 ohm ( ^{-1} cdot c m^{2} cdot e q u i v^{-1} )
respectively, the ( wedge_{infty} ) of ( N H_{4} O H ) in
( o h m^{-1} cdot c m^{2} cdot e q u i v^{-1} ) is:
A .238
в. 198
c. 22
D. 456
12
1200 Daniel cell can be represented in which of the following way?
A ( cdot Z n_{(s)}left|Z n_{(a q)}^{2+}right|left|C u_{(s)}right| C u_{(a q)}^{2} )
B. ( Z n_{(s)}left|Z n_{(a q)}^{2+}right|left|C u_{(a q)}^{2+}right| C u_{(s)} )
c. ( C u_{(s)}left|C u_{(a q)}^{2+}right|left|Z n_{(a q)}^{2+}right| Z n_{(s)} )
D. ( Z n_{(a q)}^{2+}left|Z n_{(s)}right|left|C u_{(a q)}^{a+}right| C u_{(s)} )
12
1201 Faraday’s laws of electrolysis are related to the:
A. the atomic number of the cation
B. the atomic number of anion
c. the equivalent weight of the electrolyte
D. the speed of the cation
12
1202 09. Why is standard hydrogen electrode called reversible electrode?
11. T ib lootnodi
A
12
1203 Marshall’s acid or perdisulphuric acid
( left(H_{2} S_{2} O_{8}right) ) can be prepared by
electrolytic oxidation of ( boldsymbol{H}_{2} boldsymbol{S} boldsymbol{O}_{4} ) as :
( mathbf{2} boldsymbol{H}_{2} boldsymbol{S} boldsymbol{O}_{4} rightarrow boldsymbol{H}_{2} boldsymbol{S}_{2} boldsymbol{O}_{8}+boldsymbol{2} boldsymbol{H}^{oplus}+boldsymbol{2} boldsymbol{e}^{-} )
( O_{2} ) and ( H_{2} ) are byproducts. In such an
electrolysis ( 9.72 mathrm{L} ) of ( H_{2} ) and ( 2.35 mathrm{L} ) of ( O_{2} )
were produced at S.T.P. What is the
weight of ( boldsymbol{H}_{2} boldsymbol{S}_{2} boldsymbol{O}_{8} ) formed?
12
1204 Calculate ( E^{ominus} ) for the reactions:
( Z n Y^{2-}+2 e^{-} rightleftharpoons Z n(s)+Y^{4-} ) is the
completely deprotonated anion of EDTA. The formation constant for
( Z n Y^{2-} ) is ( 3.5 times )
( mathbf{1 0}^{mathbf{1 6}} mathbf{a n d} boldsymbol{E}^{ominus} operatorname{for} boldsymbol{Z} boldsymbol{n} rightarrow boldsymbol{Z} boldsymbol{n}^{mathbf{2}+}+mathbf{2} boldsymbol{e}^{-} )
is ( 0.76 mathrm{V} )
A . ( -1.25 V )
B. ( 0.48 V )
( c .+0.68 V )
D. ( -0.27 V )
12
1205 Which one of the following has a potential more than zero?
A ( cdot P t, frac{1}{2} H_{2}(operatorname{latm}) mid H C l(1 M) )
в. ( P t_{2} frac{1}{2} H_{2}(1 a t m) mid H C l(2 M) )
c. ( quad P t, frac{1}{2} H_{2}(1 a t m) mid H C l(0.1 M) )
D ( cdot operatorname{Pt}, frac{1}{2} H_{2}(1 text { at } m) mid H C l(0.5 M) )
12
1206 Heat of reaction for the change ( Z n+ )
( boldsymbol{C u}^{2+}(mathbf{0 . 1} boldsymbol{M}) rightarrow boldsymbol{Z} boldsymbol{n}^{2+}(mathbf{1} boldsymbol{M})+boldsymbol{C u} mathbf{a t} )
( 27^{circ} C ) is:
A. ( -2.17 times 10^{5} mathrm{J} )
В. ( -2.29 times 10^{5} mathrm{J} )
c. ( -2.24 times 10^{5} J )
D. ( -1.84 times 10^{5} mathrm{J} )
12
1207 The process of giving a coating of to copper or brass is called tinning.
A. zinç
B. copper
( c . ) tin
D. iron
12
1208 Which of the following reactions is used
to make a fuel cell?
( mathbf{A} cdot C d(s)+2 N i(O H)_{3}(s) rightarrow C d O(s)+2 N i(O H)_{2}(s)+ )
( H_{2} O(l) )
( mathbf{B} cdot P b(s)+P b O_{2}(s)+2 H_{2} S O_{4}(a q) rightarrow 2 P b S O_{4}(s)+ )
( 2 H_{2} O(l) )
( mathbf{c} cdot 2 H_{2}(g)+O_{2}(g) rightarrow 2 H_{2} O(l) )
D. ( 2 F e(s)+O_{2}(g)+4 H^{+}(a q) rightarrow 2 F e^{2+}(a q)+2 H_{2} O(l) )
12
1209 The equilibrium constant ( boldsymbol{K}_{c} ) for the reaction:
( boldsymbol{C u}(boldsymbol{s})+boldsymbol{2} boldsymbol{A} boldsymbol{g}^{+}(boldsymbol{a} boldsymbol{q} cdot) rightleftharpoons boldsymbol{C} boldsymbol{u}^{2+}(boldsymbol{a} boldsymbol{q} cdot)+ )
( mathbf{2} boldsymbol{A} boldsymbol{g}(boldsymbol{s})left(boldsymbol{E}_{c e l l}^{circ}=mathbf{0 . 4 6} boldsymbol{V}right) ) will be:
A. antilog 15.6
B. antilog 2.5
c. antilog 1.5
D. antilog 12.2
12
1210 Cell constant has unit:
A ( cdot s m^{-1} )
B . ( m s^{-1} )
( mathrm{c} cdot m^{-1} )
D. ( m^{-2} )
12
1211 Lead storage cell is a secondary cell.
If true enter 1 , else enter 0
12
1212 The cell,
( Z nleft|Z n^{2+}(1 M) | C u^{2+}(1 M)right| C u, ) was
allowed to be completely discharged at 298 K. The relative concentration of ( Z n^{2+} ) to ( C u^{2+}left(frac{left[Z n^{2+}right]}{left[C u^{2+}right]}right) ) is :
( left[boldsymbol{E}_{c e l l}^{0}=mathbf{1 . 1 0} boldsymbol{V}right] )
( mathbf{A} cdot 9.65 times 10^{4} )
B . antilog (24.08)
c. 37.3
D. ( 10^{37.3} )
12
1213 Which of the following statements are
true?
A. During electrolysis, charge flows through electrolytic solution via electrons.
B. The randomly moving electrons in a metal wire will start moving in a particular direction when a potential difference is applied across it.
C. A negatively charged particle has higher electric potential than a positively charged particle.
D. Charge flows only through negative charge carriers like electrons.
12
1214 Corrosion occurs due to:
a) action of water on the metal.
b) action of air on the metal.
c) action of temperature on the metal
( A cdot a, b )
в. b,
( c cdot ) а,
D. all of the above
12
1215 The cell constant of a given cell is 0.47 ( c m^{-1} . ) The resistance of a solution
placed in this cell is measured to be
31.6 ohm. The conductivity of the solution ( left(text { in } S c m^{-1} text {where } S ) has usual right.
meaning) is:
A . 0.15
в. 1.5
c. 0.015
D. 150
12
1216 The secondary battery is such a battery:
A. which cannot be recharged
B. which can be recharged
C. which can be reused after replacing its chemical
D. which is charged by primary cells
12
1217 For ( boldsymbol{C u}(boldsymbol{s})+boldsymbol{N O}_{3}^{-}(boldsymbol{a} boldsymbol{q})+boldsymbol{H}^{+}(boldsymbol{a} boldsymbol{q}) rightarrow )
( boldsymbol{C u}^{2+}(boldsymbol{a q})+boldsymbol{N O}_{2}(boldsymbol{g})+boldsymbol{H}_{2} boldsymbol{O}(l), ) which
of the following takes place?
A. ( C u(s) ) is oxidized
B . ( H^{+}(a q) ) is oxidized
c. ( C u(s) ) is reduced
D. ( H^{+}(a q) ) is reduced
E . ( N O_{3}^{-} ) is oxidized
12
1218 A half cell reaction: ( boldsymbol{A} boldsymbol{g}_{2} boldsymbol{S}(boldsymbol{s})+boldsymbol{2} boldsymbol{e}^{-} rightarrow )
( mathbf{3} A boldsymbol{g}(s)+boldsymbol{S}^{2-} ) is carried out in a half
( operatorname{cell} P t_{A g_{2}} s mid A g, H_{2} S(0.1 M) boldsymbol{a t}left[boldsymbol{H}^{oplus}right]= )
( 10^{-3}, ) The EMF of the half cell is:
( left[boldsymbol{E}_{A boldsymbol{g}^{oplus} mid boldsymbol{A} boldsymbol{g}}^{ominus}=mathbf{0 . 8 0} boldsymbol{V}, boldsymbol{K}_{aleft(boldsymbol{H}_{2} boldsymbol{S}right)}=right. )
( left.mathbf{1 0}^{-mathbf{2 1}}, boldsymbol{a n d} boldsymbol{K}_{s p} boldsymbol{o} boldsymbol{f} boldsymbol{A} boldsymbol{g}_{2} boldsymbol{S}=mathbf{1 0}^{-49}right] )
( mathbf{A} cdot-0.1735 V )
в. ( -0.19 V )
c. ( +0.1735 V )
D. ( +0.19 V )
12
1219 In moist air, iron is oxidized to give:
( A cdot ) iron ( [I I] ) oxide
B. iron ( [I I I] ) oxide
c. iron[II] hydroxide
D. iron[II] sulphide
12
1220 During an electrolysis of conc. ( boldsymbol{H}_{2} boldsymbol{S} boldsymbol{O}_{4} )
perdisulphuric acid ( left(boldsymbol{H}_{2} boldsymbol{S}_{2} boldsymbol{O}_{8}right) ) and ( boldsymbol{O}_{2} )
form in equimolar amount. The amount
of ( boldsymbol{H}_{2} ) that will form simultaneously will
be: ( left(2 H_{2} S O_{4} rightarrow H_{2} S_{2} O_{8}+2 H^{+}+right. )
( 2 e^{-} )
A. Thrice that of ( mathrm{O}_{2} ) in moles
B. Twice that of ( 0_{2} ) in moles
c. Equal to that of ( mathrm{O}_{2} ) in moles
D. Half of that of ( mathrm{O}_{2} ) in moles
12
1221 Electrolysis is the passage of electricity through a liquid or a solution accompanied by a chemical change.
A. True
B. False
12
1222 1 g metal ( mathrm{M}^{2+} ) was discharged by the passage of ( 1.81 times 10^{22} ) electrons. What
is atomic mass of metal (write answer
as the nearest after diving atomic mass by 20)?
12
1223 Question 1. Arrange the following metals in the order in which they
displace each other from the solution of their salts. Al, Cu, Fe, Mg and Zn.
Consider the order of reactivity of metals, as a more reactive metal can
displace the less reactive metal from its salt solution.
12
1224 What is an electrochemical series? How
is it useful in predicting whether a metal can liberate hydrogen from acid or not?
12
1225 State True or False.
Corrosion of iron is a redox process.
A. True
B. False
12
1226 A current of 2 amp when passed for 5
hour through a molten salt deposits ( 22.2 g ) of metal of atomic mass 177
Then calculate the positive oxidation state of the metal in the metal salt.
12
1227 If fully charged battery contains 1.5 L of
( 5.00 mathrm{M} mathrm{H}_{2} mathrm{SO}_{4} ) in and ( 1.5 mathrm{mol} ) of ( mathrm{H}_{2} mathrm{SO}_{4} ) is
consumed, concentration of ( H_{2} S O_{4} ) after
current is drawn is:
A . 3.50
B. 2.00 M
c. ( 4.25 mathrm{M} )
D. 4.00 M
12
1228 Calculate the current strength which
was passed for 15 min to liberated ( 193.11 c m^{3} ) of hydrogen gas at ( 273 K )
and ( 760 m m ) of ( H g ) pressure during electrolysis of acidulated water
12
1229 The following are some equations about Nernst equations.
I) For metal electrode: ( E=E^{0}- )
( frac{2.303 R T}{n F} log frac{[M]}{left[M^{n+}right]} )
II) For metal electrode: ( E=E^{0}+ )
( frac{2.303 R T}{n F} log c )
III) For non-metal electrode: ( E=E^{0}- )
( frac{0.059}{n} log cleft[A^{n-}right] )
IV) For non-metal electrode: ( E=E^{0}- )
( frac{2.303 R T}{n F} log cleft[A^{n-}right] )
The correct answer is :
A. only I and III are correct
B. only II and IV are correct
C. only I and IV are correct
D. all are correct
12
1230 By process of electrolysis chemical energy gets converted into electrical
energy.
12
1231 In the reaction,
( boldsymbol{2} boldsymbol{A l}(boldsymbol{s})+boldsymbol{6} boldsymbol{H} boldsymbol{C l}(boldsymbol{a} boldsymbol{q}) rightarrow boldsymbol{2} boldsymbol{A} boldsymbol{l}^{3+}(boldsymbol{a} boldsymbol{q} cdot)+ )
( mathbf{6} C l^{-}left(a q_{cdot}right)+3 H_{2}(g) )
( mathbf{A} cdot 11.2 H_{2}(g) ) at ( mathrm{STP} ) is produced for every mole of ( H C l(a g .) ) consumed
B. 6 LHCl ( (text { ag. }) ) is consumed for every 3 L ( H_{2}(E ) ) produced
C ( .33 .6 L H_{2}(g) ) is produced regardless of temperature and pressure for every mole of ( mathrm{Al} ) that reacts
D. ( 67.2 L H_{2}(g) ) at SIT is produced for every mac of Al that reacts
12
1232 A big irregular shaped vessel container water, the specific conductance of which was ( 2.56 times 10^{-5} mathrm{mhocm}^{-1} .500 mathrm{g} )
of ( N a C l ) was the added to the water and
the specific conductance after the addition of ( N a C l, ) was found to be
( 3.10 times 10^{-5} mathrm{mhocm}^{-1} . ) The capacity of
the vessel if it is fulfilled with water is :
( left(lambda_{infty} N a C l=149.9right) )
B . ( V=2.59 times 10^{6} mathrm{cm}^{-3} )
c. ( V=3.14 times 10^{9} mathrm{cm}^{-3} )
D. none of the above
12
1233 The technique of protecting a metal from corrosion by connecting it to a second metal (that is more easily oxidised) is called:
A. annealing
B. galvanisation
c. cathodic protection
D. anodic protection
12
1234 The molar conductivity of ( N a C l, H C l )
and ( C H_{3} C O O N a ) at infinite dilution
are 126.45,426.16 and ( 91 S c m^{2} m o l^{-1} )
respectively. The molar conductivity of
( C H_{3} C O O H ) at infinite dilution is:
A ( .201 .28 S mathrm{cm}^{2} mathrm{mol}^{-1} )
B. ( 698.28 S mathrm{cm}^{2} mathrm{mol}^{-1} )
c. ( 390.71 S mathrm{cm}^{2} mathrm{mol}^{-1} )
D. ( 540.48 S mathrm{cm}^{2} mathrm{mol}^{-1} )
12
1235 Assertion
The transfer of electrons from zinc to
copper takes place through metal wire connecting the two rods.
Reason
Electricity from solution in one beaker to other flows by migration of ions through the salt bridge.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
1236 Equivalent conductivity of acetic acid at infinite dilution is ( 390.7 mathrm{mho} mathrm{cm}^{2} mathrm{gm} )
equiv and for ( 0.1 mathrm{M} ) acetic acid is 5.2
mho ( c m^{2} ) gm.equiv ( ^{2} ). Calculate degree
of dissociation, ( boldsymbol{H}^{+} ) ion concentration
and dissociation constant of the acid.
12
1237 Q. 60 Assertion (A) Mercury cell does not give steady potentia
Reason (R) In the cell reaction, ions are not involved
action, ions are not involved in solution.
AA
is
stood
12
1238 Match the following: 12
1239 For given half cell; ( A l^{+3}+3 e^{-} rightarrow A l ; ) on
increasing ( left[A l^{+3}right], ) the electrode
potential:
A. Increases
B. Decreases
c. No change
D. First increases then decreases
12
1240 From the given cells:
Lead storage cell, Mercury cell, Fuel cell and Dry cell Answer the following:
(i) Which cell is used in hearing aids?
(ii) Which cell was used in Apollo Space
Programme?
(iii) Which cell is used in automobiles
and inverters?
(iv) Which cell does not have long life?
12
1241 Which of these half-reactions
represents an oxidation?
I. ( boldsymbol{S} boldsymbol{n}^{boldsymbol{4}+} rightarrow boldsymbol{S} boldsymbol{n}^{2+} )
II. ( M n O_{4}^{-} rightarrow M n^{2+} )
III. ( boldsymbol{C l}_{2} rightarrow boldsymbol{C l O}_{mathbf{3}}^{-} )
A. I only
B. II only
c. III only
D. I and II only
E. II and III only
12
1242 Which of the following is not true?
A. The electrode which pushes electrons into external circuit is known as anode
B. The electrode which pulls electrons out of external circuit is known as cathode
C. Weak electrolytes conduct relatively small quantity of electricity than strong electrolytes
D. Effect of dilution on conductance of strong electrolyte can be explained by Arrhenius theory.
12
1243 Q. 54 Match the items of Column I and Column II.
Column 1
Column II
A. Lechlanche cell 1 Cell reaction 2H, +O, — 210
B. Ni-Cd cell 2. Does not involve any ion in solution and is
used in hearing aids
C. Fuel cell 3. Rechargeable
D. Mercury cell 4. Reaction at anode, Zn → Zn²+ + 2e
5. Converts energy of combustion into
electrical energy
12
1244 ( H_{2}-O_{2} ) fuel cell is:
A. primary cell
B. secondary cell
( c cdot ) both
D. cant be predicted
12
1245 For an electrolyte solution of ( mathbf{0 . 0 5} boldsymbol{M} ) the conductivity has been found to be
( 0.0110 mathrm{S} mathrm{cm}^{-1} . ) The molar conductivity
is:
A. ( 0.055 mathrm{Scm}^{2} mathrm{mol}^{-1} )
B. ( 550 mathrm{Scm}^{2} mathrm{mol}^{-1} )
c. ( 0.22 mathrm{Scm}^{2} mathrm{mol}^{-1} )
D. ( 220 mathrm{Scm}^{2} mathrm{mol}^{-1} )
12
1246 The standard reduction potentials of
( Z n^{2+} mid Z n ) and ( C u^{2+} mid C u ) are ( -0.76 V ) and
( +0.34 mathrm{V} ) respectively. What is the cell EMF of the following cell?
( Z nleft|Z n^{2+}(0.05 M)right|left|C u^{2+}(0.005 M)right| C u )
( left[frac{R T}{F}=0.059right] )
A . 1.1295
в. 1.0705 V
c. 1.1000
D. 1.0412 v
12
1247 Which solution will conduct the
current?
A. Sugar in water
B. Sugar in ethanol
c. lodine in ethanol
D. ( M g C l_{2} ) in water
12
1248 Which of the following energy changes
occur in galvanic cell?
A. Electrical energy ( rightarrow ) Chemical Energy
B. Chemical Energy ( rightarrow ) Electrical Energy
C. Chemical Energy ( rightarrow ) Internal Energy
D. Internal Energy ( rightarrow ) Electrical Energy
12
1249 Conductivity of a saturated solution of a sparingly soluble salt ( A B ) at ( 298 K ) is
( 1.85 times 10^{-5} S m^{-1} . ) Solubility product of
the salt ( A B ) at ( 298 K ) is :
( left[text { Given } boldsymbol{Lambda}_{boldsymbol{m}}^{o}(boldsymbol{A B})=mathbf{1 4 0} timesright. )
( left.10^{-4} S m^{2} m o l^{-1}right] )
A. ( 1.32 times 10^{-12} )
В. ( 1.74 times 10^{-12} )
C ( .5 .7 times 10^{-12} )
D. ( 7.5 times 10^{-12} )
12
1250 In hydrogen fuel cell the catalyst used ¡s/are:
This question has multiple correct options
A . ( A g )
в. ( F e )
( c cdot P t )
D. ( Z n )
12
1251 Battery charging equipment is generally installed:
A . in well ventilated location
B. in clean and dry place.
c. as near as practical to the battery being charged
D. in location having all above features
12
1252 In which of the following cells, use of salt bridge to eliminate liquid junction potential is not necessary?
A ( cdot P t H_{2}(g)|H C l| A g C l(s) mid A g )
B . ( H gleft|H g_{2} C l_{2}(s)right| K C l )saturated( |H C l(a q)| H_{2}(g) P t )
c. ( Z nleft|Z n S O_{4} | C u S O_{4}right| C u )
D. ( Z nleft|Z n S O_{4}right| F e^{3+}(a q), F e^{2+}(a q) mid P t )
12
1253 Conductivity of a solution is affected
by:
A. addition of water
B. process of heating
c. addition of acetic acid
D. all of the above
12
1254 ions is
lectrode potential for the oxidation of cl
Q. 34 Value of standard electrode potential for the oxid
more positive than that of water, even then in the ele
aqueous sodium chloride, why is Cl- oxidised at anode instead of water?
water at
12
1255 Specific conductance of ( 0.1 mathrm{M} ) NaC solution is ( 1.01 times 10^{-2} ) ohm ( ^{-1} mathrm{cm}^{-1} )
Its molar conductance in ohm ( ^{-1} mathrm{cm}^{2} )
( m o l^{-1} ) is:
A ( cdot 1.01 times 10^{2} )
B . ( 1.01 times 10^{3} )
c. ( 1.01 times 10^{4} )
D. 1.01
12
1256 The number of electrons involved in
electrode reaction by 1 coulomb charge is:
A ( cdot 6.85 times 10^{14} )
B. ( 19.85 times 10^{18} )
c. ( 6.85 times 10^{18} )
D. ( 16.85 times 10^{15} )
12
1257 Which of the following statements is
true?
A. Electrolysis is one of the applications of chemical effects of current
B. A metal wire shows chemical effect when a current is passed through it
c. Like charges attract each other
D. Charge flows only through negative charge carriers
12
1258 If for the following half-cell reactions:
( boldsymbol{C u}^{2+}+boldsymbol{e}^{-} rightarrow boldsymbol{C u}^{oplus} )
( boldsymbol{E}^{oplus}=mathbf{1 . 7 7} boldsymbol{V} )
( boldsymbol{C u}^{2+}+boldsymbol{2} boldsymbol{e}^{-} rightarrow boldsymbol{C u} )
( boldsymbol{E}^{ominus}=-mathbf{0 . 3 4} )
The ( E^{ominus} ) of the half-cell reaction will be
( (text { in } V) )
( boldsymbol{C u}^{oplus}+boldsymbol{e}^{-} rightarrow boldsymbol{C u} )
12
1259 How many electrons flow when a current
of 5 amperes is passed through a conductor for 200 seconds?
A ( cdot 6.25 times 10^{21} )
B. ( 6.025 times 10^{21} )
c. ( 6.25 times 10^{22} )
D. ( 6.025 times 10^{22} )
12
1260 Which is correct relation?
( mathbf{A} cdot A_{e q cdot(K O O C cdot C O O N a)}=frac{1}{2} lambda_{K^{+}}+frac{1}{2} lambda_{N a^{+}}+frac{1}{2} lambda_{O X^{2}} )
B. ( A_{e q .(text {KOOC} cdot text {COONa})}=lambda_{K^{+}}+lambda_{N a^{+}}+lambda_{O X^{2-}} )
C ( cdot A_{text {eq. }(text { KOOC } cdot text { COON } a)}=lambda K^{+}+lambda_{N a^{+}}+frac{1}{2} lambda_{O X^{2}-} )
D. ( A_{e q .(text {KOOC} cdot text {COONa})}=frac{1}{2} lambda_{K^{+}}+frac{1}{2} lambda_{N a^{+}}+lambda_{O X^{2}} )
12
1261 The equation representing the process by which standard reduction potential
of zinc can be defined
is
( mathbf{A} cdot Z n^{2+}(s)+2 e^{-} rightarrow Z n )
( mathbf{B} cdot Z n(g) rightarrow Z n^{2+}(g)+2 e^{-} )
( mathbf{c} cdot Z n^{2+}(g)+2 e^{-} rightarrow Z n )
D. ( Z n^{2+}(a q .)+2 e^{-} rightarrow Z n(s) )
12
1262 A steady current of 10.0 Amps is passed through a nickel production cell of 15 minutes.

Which of the following is the correct expression for calculating the number of grams of nickel produced? Note:
9. faraday( =96,500 ) Coulombs
The electroytic cell involves the following half-reaction:
( N i_{(a q)}^{2+}+2 e^{-} rightarrow N i_{(s)} )
A ( frac{(10.0)(15)(96,500)}{(59)(60)} g )
в. ( frac{(10.0)(15)(59)}{(60)(96,500)} ),
c. ( frac{(10.0)(15)(60)(59)}{(96,500)(2)} g )
D. ( frac{(96,500)(59)}{(10)(15)(60)(2)} g )

12
1263 The battery is an arrangement of an electrolytic cell connected in series.
A. True
B. False
12
1264 The resistance of ( frac{1}{10} mathrm{M} ) solution is ( 2.5 times ) ( 10^{3} ) ohm. What is the molar conductivity
of solution? (cell constant= ( 1.25 mathrm{cm}^{-1} ) )
A. 3.5 ohm ( ^{-1} c m^{2} ) mol ( ^{-} )
B. 5.0 ohm ( ^{-1} c m^{2} ) mol ( ^{-} )
c. 2.5 ohm( ^{-1} mathrm{cm}^{2} ) mol ( ^{-1} )
D. 2.0 ohm ( ^{-1} mathrm{cm}^{2} ) mol-
12
1265 During the charging of lead storage battery, the reaction at anode is
represented by:
A ( cdot P b^{2+}+S O_{4}^{2-} rightarrow P b S O_{4} )
B . ( P b S O_{4}+2 H_{2} O rightarrow P b O_{2}+S O_{4}^{2-}+4 H^{+}+2 e )
c. ( P b rightarrow P b^{2+}+2 e )
( mathbf{D} cdot P b^{2+}+2 e rightarrow P b )
12
1266 For ( Z n^{2+} / Z n, E^{circ}=-0.76 V, ) for
( boldsymbol{A} boldsymbol{g}^{+} / boldsymbol{A} boldsymbol{g}, boldsymbol{E}^{circ}=mathbf{0 . 7 9 9} boldsymbol{V} . ) The correct
statement is:
A. the reaction Zn getting reduced Ag getting oxidized is spontaneous
B. Zn undergoes reduction and Ag is oxidized
C. zn undergoes oxidation Ag gets reduced
D. No suitable answer
12
1267 Q Type your question
( A )
( B )
( c )
ect presenta
12
1268 Which metal is usefull for protection of iron by corrosion?
A. Aluminium
B. Sodium
c. zinc
D. copper
12
1269 Which of the following is an example of simple fuel cell?
A. Lead storage battery
B. Leclanche cell
c. ( H_{2} O_{2} )
D. All of the above
12
1270 The following are some statements about
galvanic cell.
1) The cell reaction will be obtained by
summing up the reactions in the two half
cells.
2) ( E^{0} ) cell ( =E^{0} ) cathode ( -E_{text {Anode }}^{0} )
3) ( E_{C e l l}^{0}=E_{text {reduction electrode }}^{0}-E_{text {oxidation electrode }}^{0} )
4) ( E^{0} ) Cell ( =E^{0}_{L . H . E}-E^{0} R . H . E )
The correct combination is :
A. only I and III are correct
B. only I and II are correct
C. only I,II,III are correct
D. all are correct
12
1271 Solution. Methane (CH) and neu (o
Question 15. Explain how rusting of iron is envisaged as setting up of an
electrochemical cell.
se Rusting of iron is a redox reaction, it involves the oxidation of Fe and Fe*
and reduction of O2.
12
1272 Which one is the most powerful oxidizing
agent?
( mathbf{A} cdot C l_{2}+2 e^{-} rightarrow 2 C l^{-}, quad E^{o}=1.36 V )
B. ( N a^{+}+e^{-} rightarrow N a, quad E^{o}=-2.71 V )
( mathbf{c} cdot M n O_{4}^{-}+2 H_{2} O+3 e^{-} rightarrow M n O_{2}+4 O H^{-}, quad E^{o}= )
( 0.6 V )
( mathbf{D} cdot H_{2} O_{2}+2 H^{+}+2 e^{-} rightarrow 2 H_{2} O, quad E^{o}=1.78 V )
12
1273 Electrolysis of water to form hydrogen and oxygen gas is called
A. precipitation
B. oxidation-reduction
c. distillation
D. hydration
E. condensation
12
1274 Assertion
In electrochemical cell, we can not use
KCl in the salt bridge if anodic or
cathodic compartment consists of ( mathrm{Ag}^{+} )
or ( P b^{2+} ) ion.
Reason
Salt bridge is employed to maintain the electrical neutrality and to minimize the liquid-liquid junction potential.
A. Both Assertion and Reason are correct and Reason is
the correct explanation for Assertion.
B. Both Assertion and Reason are correct but Reason is
not the correct explanation for Assertion.
C. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
1275 The ( Delta H ) for the reaction at ( 0^{circ} mathrm{C} )
( Z n+2 A g C l rightarrow Z n C l_{2}+2 A g )
is -52.05 kcal. If the e.m.f. of the cell is
1.015 volt, the temperature coefficient of
the cell at ( 0^{circ} mathrm{C} ) in ( V /^{o} C ) is:
A . ( -4.311 times 10^{-4} )
В . ( 2.388 times 10^{-4} )
c. ( 4.311 times 10^{-4} )
D. ( 4.311 times 10^{-5} )
12
1276 Chromium metal can be plated out from an acidic solution containing ( boldsymbol{C r} boldsymbol{O}_{3} ) according to the following equation.
[
begin{array}{c}
boldsymbol{C r} boldsymbol{O}_{3}(boldsymbol{a q})+boldsymbol{6} boldsymbol{H}^{+}+boldsymbol{6} boldsymbol{e}^{-} rightarrow \
boldsymbol{C r}(boldsymbol{s})+boldsymbol{3} boldsymbol{H}_{2} boldsymbol{O}
end{array}
]
How many grams of chromium will be plated out by 24000 coulombs?
A. ( 0.78 g )
B. ( 0.45 g )
c. ( 1.2 g )
D. None of these
12
1277 Consider the following ( E^{0} ) values:
( E_{F e^{3+} / F e^{2+}}^{0}=+0.77 V ; E_{S n^{2+} / S n}^{0}=-0.14 V )
Under standard conditions the EMF for
the reaction
( S n_{(s)}+2 F e_{(a q)}^{3+} rightarrow 2 F e^{2+}_{(a q)}+S n_{(a q)}^{2+} ) is :
A . ( 1.68 mathrm{v} )
B . ( 1.40 mathrm{V} )
c. ( 0.91 v )
D. ( 0.63 mathrm{v} )
12
1278 Question 17. Consider a cell given below Cu Cu2+||0rCl2, Pt.
Write the reactions that occur at anode and cathode.
2+
12
1279 The standard reduction potentials of ( boldsymbol{C u}^{2+} / boldsymbol{C u} ) and ( boldsymbol{C u}^{2+} / boldsymbol{C u}^{+} ) are ( boldsymbol{0 . 3 3 7} )
and ( 0.153 mathrm{V} ) respectively. The standard electrode potential of ( C u^{+} / C u ) half cell
is:
A . ( 0.184 mathrm{v} )
B. ( 0.827 mathrm{V} )
c. ( 0.521 mathrm{v} )
D. ( 0.490 v )
12
1280 For the galvanic cell pictured below, determine the electrochemical
potential for the system at ( 25^{circ} mathrm{C} )
Note: ( boldsymbol{C u}_{(a q)}^{2+}+boldsymbol{2} boldsymbol{e}^{-} rightarrow boldsymbol{C u}_{(s)} boldsymbol{E}^{circ}= )
( mathbf{0 . 3 3 7} mathbf{V} )
( Z n_{(a q)}^{2+}+2 e^{-} rightarrow Z n_{(s)} E^{circ}=-0.763 V )
A. ( -0.426 V )
В. ( -1.10 v )
( mathbf{c} .+0.426 V )
D. ( +1.10 v )
12
1281 Explain the following terms with one
example each.
(a) Corrosion
(b) Rancidity
12
1282 What is ( X ), in the following reaction?
( boldsymbol{K} boldsymbol{H} boldsymbol{S} boldsymbol{O}_{4}+boldsymbol{F}_{2} rightarrow boldsymbol{H} boldsymbol{F}+boldsymbol{X} )
A. ( K_{2} S O_{4} )
в. ( K_{2} S_{2} O_{4} )
( mathbf{c} cdot K_{2} S_{2} O_{3} )
D. ( K_{2} S_{2} O_{8} )
12
1283 What is Primary Battery? Give one
example.
12
1284 How many electrons constitute current
of one micro ampere in one second?
( mathbf{A} cdot 6.25 times 10^{8} )
B. ( 6.25 times 10^{12} )
( mathbf{C} cdot 6.25 times 10^{9} )
D. ( 6.25 times 10^{15} )
12
1285 Conductivity of ( 2.5 times 10^{-4} ) M methanoic
acid is ( 5.25 times 10^{-5} S c m^{-1} . ) Calculate it
molar conductivity and degree of dissociation.
( left(text { Given: } boldsymbol{lambda}^{0}left(boldsymbol{H}^{+}right)=right. )
( mathbf{3 4 9 . 5 s} mathrm{cm}^{2} ) mol ( ^{-1} ) and ( lambda^{0}left(mathrm{HCOO}^{-}right)= )
( left.50.5 S c m^{2} m o l^{-1}right) )
12
1286 Calculate the potential of hydrogen
electrode in contact with a solution
whose ( p H ) is 10
12
1287 For the following sequential reaction ( boldsymbol{E}^{boldsymbol{o}} ) values in volts at ( 298 mathrm{K} ) are given:
( M n O_{4}^{-0.564}^{V} M n O_{4}^{-2}^{2.26 V} )
( M n O_{2} stackrel{0.95}{rightarrow} M n^{+3} stackrel{1.51 V}{rightarrow} M n^{+2} )
Calculate ( boldsymbol{E}^{o} ) for ( boldsymbol{M} boldsymbol{n} boldsymbol{O}_{boldsymbol{4}}^{-} rightarrow boldsymbol{M} boldsymbol{n}^{+2} )
A. -1.81 volt
B. -1.18 volt
c. 1.51 volt
D. 1.18 volt
12
1288 When one faraday of electricity is passed through three electrolytic cells containing ( boldsymbol{A} boldsymbol{g}^{+}, boldsymbol{N} boldsymbol{i}^{2+} ) and ( boldsymbol{C} boldsymbol{r}^{3+} ) ions
respectively, the deposited ( A g ) (At. mass ( =108), N i(text { At. mass }=59) ) and
( boldsymbol{C r}(boldsymbol{A} boldsymbol{t} . boldsymbol{m} boldsymbol{a} boldsymbol{s} boldsymbol{s}=mathbf{5} boldsymbol{2}) )
are
A. ( A g=108 g, N i=29.5 g, C r=17.3 mathrm{g} )
в. ( A g=108 g, N i=59 g, C r=52 g )
c. ( A g=108 g, N i=108 g, C r=17.3 g )
D. ( A g=108 g, N i=29.5 g, C r=166 g )
12
1289 What is SHE? Explain its construction and application. 12
1290 Assertion
A greenish layer appears on copper vessels, if left uncleaned.
Reason
It is due to the formation of a layer of basic copper carbonate.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
1291 A certain current liberated 0.504 g of
hydrogen in 2 hours. How many grams of copper can be liberated by the same current flowing for the same time in copper sulphate solution?
A. ( 31.8 mathrm{g} )
B. ( 16.0 mathrm{g} )
c. ( 12.7 mathrm{g} )
D. ( 63.5 mathrm{g} )
12
1292 When a lead storage battery is
discharged:
A. ( S O_{2} ) is evolved
B. lead sulphate is consumed
( mathrm{c} ). lead is formed
D. sulphuric acid is consumed
12
1293 ( N_{2}+O_{2}+H e a t rightarrow 2 N O )
( (g) )
( boldsymbol{q} )
( boldsymbol{C}_{(boldsymbol{s})}+boldsymbol{O}_{boldsymbol{2}(boldsymbol{g})} rightarrow boldsymbol{C} boldsymbol{O}_{boldsymbol{2}(boldsymbol{g})}+boldsymbol{Q} )
What information do you get from the above equations ? Comment. Write an activity about how you conduct an experiment to show that more
reactive metals replace less reactive metals from their compounds.
12
1294 In hydrogen evolution type of corrosion
with respect to hydrogen electrode which
of the following is correct?
A. the metal with more negative SRP value under the given conditions
B. the metal with more positive SRP value under the given conditions
C. the metal with both negative and positive SRP values
D. All the above
12
1295 A solution of ( X S O_{4} ) is electrolyed. When a constant current of 2.0 amperes is applied for 800 minutes, ( 4.5 g ) of the unknown metal X is deposited. Identify the unknown metal, X.
A. ( C d )
в. ( B e )
c. ( M g )
D. ( C u )
12
1296 During electrolysis, cations move towards the positive terminal.
A. True
B. False
12
1297 Electrochemistry
75
Question 10. If a current of 0.5 ampere flows through a metallic wire
for 2 h, then how many electrons would flow through the wire?
(0) Find charge by using. Q = it.
(ii) When charge 1 Faraday (96500 C) flows; number of electrons is equal
to 6.022 x102. So, calculate the number of electrons when charge is
Qby unitary method.
12
1298 Which of the following statements is true for fuel cells?
A. They are more efficient
B. They are free from pollution
c. They run till reactants are active
D. All of the above
12
1299 Substance which give good conducting aqueous solution are called:
A. weak electrolytes
B. strong electrolytes
c. non-electrolytes
D. catalysts
12
1300 The weight of silver (At. Wt. = 108) displaced by a quantity of electricity
which displaces ( 5600 mathrm{ml} ) of ( O_{2} ) at STP will be
A. ( 5.4 mathrm{g} )
B. ( 10.8 mathrm{g} )
c. ( 54.0 mathrm{g} )
D. ( 108.0 mathrm{g} )
12
1301 SULLULLLERI
LETTULLE
Q28. Arrange the following metals in the order in which they displace each other from the solution
of their salts.
Al, Cu, Fe, Mg and Zn.
Ttia bang
Tha
12
1302 Question 2. Given the standard electrode potentials,
K/K =-2.93 V, Agt / Ag=0.80 V
Hg2+ /Hg = 0.79V,
Mg2+ /Mg=-2.37 V,
Cr3+/ Cr=-0.74 V
Arrange these metals in their increasing order of reducing power.
Reducing power & Reduction potential
– i.e., as the reduction potential
decreases, reducting power increases. So, arrange the given metals on
this basis.
12
1303 A current of ( 10.0 mathrm{A} ) flows for ( 2.00 mathrm{hrs} ) through an electrolytic cell containing a molten salt of metal ( X . ) This results in
the decomposition of 0.250 mol of metal ( X ) at the cathode. The oxidation state of ( X ) in the molten salt is: ( (F= )
( 96500 C) )
( A cdot+1 )
( B cdot+2 )
( c cdot+3 )
( D cdot+4 )
12
1304 According to the Nernst equation, the potential of an electrode changes by
( mathbf{5 9 . 2} boldsymbol{m} boldsymbol{V} ) whenever the ratio of the
oxidized and the reduced species
changes by a factor of 10 at ( 25^{circ} mathrm{C} ). What would be the corresponding change in the electrode potential if the
experiment is carried out at ( 30^{circ} mathrm{C} ) ?
A. ( 59.2 mathrm{mV} )
в. ( 71.0 mathrm{mV} )
c. ( 60.2 mathrm{mV} )
D. None of above
12
1305 What is corrosion? Explain whether gold ornaments corrode or not 12
1306 Given the standard potential of the
following at ( 25^{circ} mathrm{C} . M n O_{2} rightarrow M n^{3+} )
( boldsymbol{E}^{ominus}=mathbf{0 . 9 5} boldsymbol{V} )
( M n^{3+} rightarrow M n^{2+} ; E^{ominus}=1.51 V )
The standard potential of ( M n O_{2} rightarrow )
( M n^{2+} ) is:
A. ( -0.56 V )
B . ( -2.46 V )
c. ( -1.23 V )
D. ( 1.23 V )
12
1307 How many moles of electrons wil
together contribute to the charge of 289500 coulomb?
12
1308 An electrolytic cell contains a solution
of ( A g_{2} S O_{4} ) and has platinum
electrodes. A current is passed until
( 1.6 g ) of ( O_{2} ) has been liberated at anode. The amount of silver deposited at cathode will be
A. ( 108 g )
B. ( 1.6 g )
( mathrm{c} .0 .8 mathrm{g} )
D. 21.60 ( g )
12
1309 Explain rancidity. 12
1310 Silver is monovalent and has an atomic
mass of ( 108 . ) Copper is divalent and has an atomic mass of ( 63.6 . ) The same
electric current is passed, for the same length of time through a silver
coulometer and a copper coulometer. If ( 27.0 mathrm{g} ) of silver is deposited, then the corresponding amount if copper deposited is:
A. ( 31.80 g )
B. 15.90 g
c. ( 7.95 mathrm{g} )
D. none of these
12
1311 Explain the term with example:Oxidant 12
1312 What is the other name of ( S H E ? )
A. Concentration cell
B. Inactive electrode
c. Reference electrode
D. Active electrode
12
1313 Internal resistance of a battery cell
decreases with:
A. an increase in area of the plates inside the electrolyte
B. an increase in distance between the two electrodes
c. a decrease in size of the electrodes
D. an increase of age of the battery
12
1314 Given that the standard reduction
potentials for ( M^{+} / M ) and ( N^{+} / N )
electrodes at ( 298 K ) are ( 0.52 V ) and
( 0.25 V ) respectively. Which of the following is correct in respect of the following electrochemical cell?
( boldsymbol{M}left|boldsymbol{M}^{+} | boldsymbol{N}^{+}right| boldsymbol{N} )
A. The overall cell reaction is a spontaneous reaction
B. The standard EMF of the cell is ( -0.27 V )
c. The standard EMF of the cell is ( 0.77 V )
D. The standard EMF of the cell is ( -0.77 V )
E. The standard EMF of the cell is ( 0.27 V )
12
1315 In producing chlorine through electrolysis 100 watt power at 125 V is being consumed. How much chlorine
per minute is liberated?

Electrochemical Equivalent of chlorine is ( 0.367 times 10^{-6} ) kg/coulomb:
A. ( 21.3 mathrm{mg} )
в. ( 17.6 mathrm{mg} )
c. ( 24.3 mathrm{mg} )
D. ( 13.6 mathrm{mg} )

12
1316 Write two methods of preventing the rusting of iron 12
1317 Calculate the standard oxidation
potentials of zinc electrode form the
following data. The EMF of the cell :
( boldsymbol{L} boldsymbol{i}|boldsymbol{L} boldsymbol{i} oplus(mathbf{0 . 0 5} boldsymbol{M}) | boldsymbol{A} boldsymbol{n}| boldsymbol{Z} boldsymbol{n}^{2+}(boldsymbol{0} . boldsymbol{5} boldsymbol{M}), boldsymbol{E} )
( -3.045 V, ) is ( 2.35 mathrm{V} ) at ( 25^{circ} mathrm{C} )
12
1318 Why do caesium ( (C s) ) and potassium
( K ) ) find applications in photoelectric
cells?
12
1319 The molar conductivities of ( boldsymbol{K} boldsymbol{C} boldsymbol{I} )
( N a C l ) and ( K N O_{3} ) are 152,128 and
( 111 S c m^{2} m o l^{-1} ) respectively. What is
the molar conductivity of ( N a N O_{3} ? )
A ( cdot 101 S mathrm{cm}^{2} mathrm{mol}^{-1} )
B. ( 87 S mathrm{cm}^{2} mathrm{mol}^{-1} )
c. ( -101 S mathrm{cm}^{2} mathrm{mol}^{-1} )
D. ( -391 S mathrm{cm}^{2} mathrm{mol}^{-} )
12
1320 topp
Tropovur
precipitation. Which of the following netric titration
vs NaO
axis ( Rightarrow ) Volume of alkali adde
y-axis ( Rightarrow ) conductivity
12
1321 State Faraday’s first law of electrolysis. 12
1322 Which of the following indicates that a potato is a conductor of electricity?
A. Greenish blue spot on potato around one wire.
B. Greenish blue spot on potato around both wires.
c. Blue color spot on potato around one wire.
D. Blue color spot on potato around both wires
12
1323 When electric current is passed
through water, hydrogen is deposited
over:
A. positive pole
B. negative pole
c. no dissociation
D. both the poles
12
1324 In a cell that utilizes the reaction ( Z n(s) )
( +2 H^{+}(a q) rightarrow Z n^{2+}(a q)+H_{2}(g) )
addition of ( mathbf{H}_{2} mathbf{S} mathbf{O}_{4} ) to cathode
compartment, will:
A. lower the E and shift equilibrium to the left
B. lower the E and shift the equilibrium to the right
c. increase the ( mathrm{E} ) and shift the equilibrium to the right
D. increase the E and shift the equilibrium to the left
12
1325 Primary battery is a battery:
A. which can be recharged.
B. which cannot be reconditioned by replacing chemical.
c. which cannot be reused.
D. which cannot be recharged.
12
1326 The standard electrode potentials of ( Z n )
and ( N i ) respectively are ( -0.76 mathrm{V} ) and
( -0.25 mathrm{V} . ) Then the standard emf of the
spontaneous cell by coupling these under standard conditions is:
( A cdot+1.01 v )
B. – 0.51 V
( c cdot+0.82 v )
( D cdot+0.25 v )
( mathrm{E} cdot+0.51 mathrm{v} )
12
1327 Number of faradays required to convert 1 mole of ( boldsymbol{C r}_{2} boldsymbol{O}_{mathbf{7}}^{2-} ) into ( boldsymbol{C r}^{mathbf{3}+} ) ions is
( A cdot 6 )
B. 4
( c cdot 3 )
D. none of these
12
1328 Total charge required for the oxidation of two moles ( M n_{3} O_{4} ) in to ( M n O_{4}^{2-} ) in
presence of alkaline medium is:
A. ( 5 F )
в. 10F
c. २०
D. None of these
12
1329 Question 12. Unlike dry cell, the mercury cell has a constant cell
potential throughout its useful life why?
12
1330 The potential of the cell at ( 25^{circ} mathrm{C} ) is Given
( p K_{a} ) of ( C H_{3} C O O H ) and ( p K_{b} ) of
( N H_{4} O H=4.74 )
A . ( -0.04 V )
В. ( 0.04 V )
( c .-0.189 V )
( V )
D. ( 0.189 V )
12
1331 When electric current is passed
through water, the dissociation is indicated
A. in the form of bubbles
B. by color change
( c . ) both a and ( b )
D. none of above
12
1332 A constant voltage is applied between the two ends of a uniform metallic wire.
Some heat is developed in it. The heat developed is double if:
A. both the length and radius of wire are halved
B. both length and radius of wire are doubled
c. the radius of wire is doubled
D. the length of the wire is doubled
12
1333 A flash light cell reaction is :
( mathbf{2} M n O_{2}+Z n^{2+}+2 e^{-} longrightarrow Z n+ )
( M n_{2} O_{4} . ) The current rating of the
flashlight is ( 4.6 mathrm{mA} ). The time for which we can use this light, if we start
with 3.5 g of ( M n O_{2} ) is:
A ( .8 .44 times 10^{5} s )
B. ( 8.76 times 10^{5} s )
c. ( 8.96 times 10^{5} s )
D. None of these
12
1334 On passing ( 1.5 F ) charge, the number of moles of aluminum deposited at the
cathode is:
[Molar mass of ( boldsymbol{A l}=mathbf{2 7} ) gram mol ( ^{-1} ) ]
A . 1.0
в. 13.5
c. 0.50
D. 0.75
12
1335 Assertion
n electrolysis, the quantity of electricity needed for depositing 1 mole of silver is different from that required for 1 mole
of copper.
Reason
The molecular weights of silver and
copper are different.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
1336 What is Kohlrausch’s law? 12
1337 Which of the following statement(s) is correct while conducting electricity through vegetable oil?
A. The liquid (vegetable oil) allows the electric current to pass through. since, it is a good conductor of electricity.
B. The circuit of the tester is complete but the bulb does not glow.
c. The circuit of the tester is not complete and hence the bulb does not glow.
D. Both A and B
12
1338 If mercury is used as cathode in the
electrolysis of aqueous NaCl solution, the ions discharged at cathode are:
( mathbf{A} cdot mathbf{H}^{mathbf{t}} )
B. Nat
c. он
D. cᅵ
12
1339 Consider the following half-cell
reactions and associated standard half-
cell potentials and determine the
maximum voltage that can be obtained by combination resulting in
spontaneous processes:
( boldsymbol{A u} boldsymbol{B r}_{4}^{-}(boldsymbol{a q})+boldsymbol{3} boldsymbol{e}^{-} rightarrow boldsymbol{A u}(boldsymbol{s})+ )
( 4 B r^{-}(a q) ; E^{circ}=-0.86 V )
( boldsymbol{E} boldsymbol{u}^{3+}(boldsymbol{a} boldsymbol{q})+boldsymbol{e}^{-} rightarrow boldsymbol{E} boldsymbol{u}^{2+}(boldsymbol{a} boldsymbol{q}) ; boldsymbol{E}^{circ}= )
( -0.43 V )
( boldsymbol{S} boldsymbol{n}^{2+}(boldsymbol{a} boldsymbol{q})+boldsymbol{2} boldsymbol{e}^{-} rightarrow boldsymbol{S} boldsymbol{n}(boldsymbol{s}) ; boldsymbol{E}^{circ}= )
( -0.14 V )
( boldsymbol{I O}^{-}(boldsymbol{a} boldsymbol{q})+boldsymbol{H}_{2} boldsymbol{O}(l)+boldsymbol{2} boldsymbol{e}^{-} rightarrow )
( boldsymbol{I}^{-}(boldsymbol{a} boldsymbol{q})+boldsymbol{2} boldsymbol{O} boldsymbol{H}^{-}(boldsymbol{a} boldsymbol{q}) ; boldsymbol{E}^{circ}=+mathbf{0 . 4 9} boldsymbol{V} )
( mathbf{A} cdot+0.72 )
B. +1.54
c. +1.00
D. +1.35
12
1340 Rusting of iron is prevented by
A. applying paint
B. keeping in contact with water
c. keeping in contact with oxygen
D. reacting with acid
12
1341 Coulomb is an unit of charge while ampere is the rate at which it flows.
If true enter 1 , else enter 0 .
12
1342 Pure water is a ( -=—— ) conductor of
electricity.
A. good
B. bad
c. semi
D. none of the above
12
1343 A current of ( 4.0 mathrm{A} ) is passed for 5 hours
through 1L of 2M solution of nitrate using two nickel electrodes. The molarity of the solution at the end of the electrolysis will be:
A . 1.5 м
в. 1.2
c. ( 2.5 mathrm{M} )
D. 2.0 M
12
1344 requires a salt bridge.
A. Voltaic cell
B. Electrolytic cell
C . Geiger counter
D. pH meter
E . Calorimeter
12
1345 Electrolysis of dilute aqueous ( mathrm{NaCl} ) solution was carried out by passing 10 milli ampere current. The time required
to liberate 0.01 mol of ( mathbf{H}_{2} ) gas at the
cathode is (1 Faraday ( =mathbf{9 6 5 0 0 C} ) mol ( ^{-1} ) )
A ( cdot 9.65 times 10^{4} mathrm{sec} )
B . ( 19.3 times 10^{4} mathrm{sec} )
c. ( 28.95 times 10^{4} ) sec
D. ( 38.6 times 10^{4} mathrm{sec} )
12
1346 Which of the following equations are
correctly represented for ( 0.10 mathrm{M} ) solution of acetic acid in water?
( mathbf{A} cdot[H O A c]=[H O A c c]_{e q .}+left[O A c^{-}right]_{e q .}=0.10 mathrm{M} )
B . ( left[H^{+}right]_{e q .}=left[O A c^{-}right]_{e q .}+left[O H^{-}right]_{e q} )
( mathbf{c} cdotleft[H^{+}right]>left[O H^{-}right] )
D. All of the above
12
1347 At ( 25^{circ} C ), the standard emf of a cell
having reaction involving two electrons change is found to be ( 0.295 V ). The
equilibrium constant of the reaction is
( mathbf{A} cdot 29.5 times 10^{-2} )
B. 10
( c cdot 1 times 10^{10} )
0
D . ( 29.5 times 10^{10} )
12
1348 In which of the following the corrosion of
iron will be most rapid?
A. In pure water
B. In pure oxygen
C. In air and moisture
D. In air and saline water
12
1349 Cathodic standard reduction potential
minus anodic standard reduction
potential is equal to:
A. Faraday
B. Coulomb
c. cell potential
D. Ampere
12
1350 The standard free energies of formation
of ( boldsymbol{H}_{2} boldsymbol{O}_{(l)}, boldsymbol{C} boldsymbol{O}_{2}(g) ) an n-pentane are
( -237.2 k J,-394.4 k J,-8.2 k J . ) Then
the value of ( E^{0} ) for pentane-oxygen fuel
cell is:
A . ( 1.1 V )
в. ( 0.1 V )
( c .2 .0 V )
D. 2.3V
12
1351 What is standard hydrogen electrode?
How is it prepared? Explain with labelled diagram?
12
1352 Expalin the following:
The ( E^{o} c u^{21} / c u ) for copper metal is
positive ( (+0.34), ) unlike the remaining members of the first transition series
12
1353 The unit of conductance is
and that of specific
conductance is
( mathbf{A} cdot operatorname{oh} m^{-1} ; o h m^{-1} c m^{2} )
B . ( o h m^{-1} c m^{2} ; ) ohm ( ^{-1} c m^{-1} )
( mathbf{c} cdot o h m^{-1} c m^{-1} ; o h m^{-1} c m^{2} )
D. ( o h m^{-1} ; o h m^{-1} c m^{-1} )
12
1354 Galvanizing is a process of coating iron with a metal to prevent it from rusting. The metal is:
A . tin
B. zinç
c. copper
D. silver
12
1355 At ( 25 C ) molar conductance of 0.1 molar
aqueous solution of ammonium hydroxide is 9.54 ohm ( ^{1} c m^{2} ) mol ( ^{1} ) and at
infinite dilution its molar conductance
is 238 ohm ( ^{1} mathrm{cm}^{2} ) mol ( ^{1} ). The degree of
ionisation of ammonium hydroxide at the same concentration and
temperature is:
A. ( 2.080 % )
B. 20.800 %
c. 4.008 %
D. ( 40.800 % )
12
1356 Assertion
The cell potential of mercury cell is ( 1.35 V, ) which remains constant.
Reason

In mercury cell, the electrolyte is a paste of ( K O H ) and ( Z n O )
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct

12
1357 After electrolysis of a sodium chloride
solution with inner electrodes for a
certain period of time, ( 600 mathrm{mL} ) of the ( 1 mathrm{N} )
solution was left which was found to be
NaOH. During the same time 31.80 g of Cu was deposited in copper voltameter in series with the electrolytic cell. The % yield of NaOH obtained will be:
(Atomic mass of ( C u=63.6 .) )
12
1358 Explain corrosion on the basis of following points :
(i) Definition
(ii) Factors affecting any two
(iii) Prevention of corrosion any two
12
1359 Assertion
Reason
A. assertion is true, reason is true; reason is correct explanation for assertion.
B. assertion is true, reason is true; reason is NOT a correct explanation for assertion.
C. assertion is true, reason is false.
D. assertion is false, reason is true.
12
1360 The standard reduction potentials ( boldsymbol{E}^{circ} )
for ( boldsymbol{O C l}^{-} / boldsymbol{C l}^{-} ) and for ( boldsymbol{C l}^{-} / mathbf{1} / mathbf{2 C l}_{2} ) are
( 0.86 V ) and -1.10 volt respectively. The
( boldsymbol{E}^{circ} ) value of ( boldsymbol{O C l}^{-} / mathbf{1} / mathbf{2} boldsymbol{C l}_{mathbf{1}} ) will be ( boldsymbol{?} )
( mathbf{A} cdot+1.96 V )
B . ( -1.96 V )
c. ( +0.24 V )
D. ( -0.24 V )
12
1361 Explain normal or standard hydrogen electrode. 12
1362 When electricity is passed through a solution of ( A l C l_{3}, 13.5 ) g of Al are deposited. The number of Faradays of electricity passed is: ( write your answer to nearest integer) 12
1363 Which cell of the following will measure standard electrode potential of copper electrode?
A ( cdot P t_{(s)}left|H_{2}(g, 0.1 b a r)right| H^{+}(a q, 1 M) | C u^{2+}(a q, 1 M) mid C u )
B . ( P t_{(s)}left|H_{2}(g, 1 b a r)right| H^{+}(a q, 1 M)|| C u^{2+}(a q, 2 M) mid C u )
C ( cdot P t_{(s)}left|H_{2}(g, 1 b a r)right| H^{+}(a q, 1 M)|| C u^{2+}(a q, 1 M) mid C u )
D. ( P t_{(s)}left|H_{2}(g, 1 b a r)right| H^{+}(a q, 0.1 M)|| C u^{2+}(a q, 1 M) mid C u )
12
1364 Using the information in the preceding problem, calculate the solubility
product of ( A g I ) in water at ( 25^{0} C )
( left[boldsymbol{E}_{boldsymbol{A} boldsymbol{g}^{+}, boldsymbol{A} boldsymbol{g}}^{boldsymbol{o}}=+mathbf{0 . 7 9 9} quad boldsymbol{v o l t}right] )
A ( cdot 1.97 times 10^{-17} )
В. ( 7.91 times 10^{-17} )
c. ( 1.79 times 10^{-17} )
D. ( 9.17 times 10^{-17} )
12
1365 Assertion: The standard potential of
( boldsymbol{C l}^{ominus}|boldsymbol{A} boldsymbol{g} boldsymbol{C l}| boldsymbol{A} boldsymbol{g} ) half cell is related to that
of ( boldsymbol{A} boldsymbol{g}^{ominus} mid boldsymbol{A} boldsymbol{g} )
Reason:
( boldsymbol{E}_{boldsymbol{A} boldsymbol{g}^{ominus} mid boldsymbol{A} boldsymbol{g}}^{ominus}=boldsymbol{E}_{C l^{ominus}|A boldsymbol{g} C l| boldsymbol{A} boldsymbol{g}}^{ominus}+frac{boldsymbol{R} boldsymbol{T}}{boldsymbol{F}} ln boldsymbol{K}_{s p} )
( (A g C mid) )
A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c. Assertion is true but Reason is false
D. Assertion is false but Reason is true
E. Both Assertion and Reason are false
12
1366 To protect iron from corrosion and rust,
it is coated by:
A. Tin
B. Copper
c. zinc
D. Mercury
12
1367 In the manufacture of ( A l, A l_{2} O_{3} ) is
dissolved in ( N a_{3} A l F_{6} ) at ( 300 K ) and
electrolysed between ( A l ) and carbon electrodes following the net reaction,
( mathbf{2} boldsymbol{A} boldsymbol{l}_{2} boldsymbol{O}_{3}(boldsymbol{s} boldsymbol{o l u t i o n})+boldsymbol{3} boldsymbol{C} rightarrow boldsymbol{4} boldsymbol{A l}(l)+ )
( mathbf{3} boldsymbol{C} boldsymbol{O}_{2}(boldsymbol{g}) )
The minimum voltage required between the electrodes if the Gibbs energy
change for the above reaction is -1370 ( k J m o l^{-1} ) is ( _{-1} ) (write nearest
integer)
12
1368 A lead storage battery has initially ( 200 g ) of lead and ( 200 g ) of ( P b O_{2}, ) plus
excess ( boldsymbol{H}_{2} boldsymbol{S} boldsymbol{O}_{4} . ) How long could this cell deliver a current of 10 amp, without
recharging, if it was possible to operate it so that the reaction goes to completion?
A. 2.48 hour
B. 3.48 hour
c. 4.48 hour
D. 6.48 hour
12
1369 A solution containing ( boldsymbol{N} boldsymbol{a}^{oplus}, boldsymbol{N} boldsymbol{O}_{3}^{ominus}, boldsymbol{C l}^{ominus} )
and ( S O_{4}^{2-} ) ions, all at unit concentrations, is electrolyzed between nickel anode and plantinum cathode. As the current is passed through the cell :
This question has multiple correct options
A. pH of the cathode increases
B. Oxygen is the major product at anode
c. Nickel is deposited at cathode
D. Chlorine is the maior product at anode
12
1370 Question 12. Consider the reaction,
Cr 0- +14H+ + 6e 2 Cr3+ + 7H,0
What is the quantity of electricity in coulombs needed to reduce 1 mole of
Cr2O ?
12
1371 The number of electrons delivered at the
cathode during electrolysis by a current
of 1 ampere in 60 seconds is :
(charge on an electron is ( 1.60 times ) ( left.10^{-19} Cright): )
( mathbf{A} cdot 3.75 times 10^{20} )
B . ( 7.48 times 10^{23} )
( c cdot 6 times 10^{23} )
D. ( 6 times 10^{20} )
12
1372 Given the standard half-cell potentials
( left(E^{o}right) ) of the following as
( Z n=Z n^{2+}+2 e^{-} ; quad E^{o}=+0.76 mathrm{V} )
( boldsymbol{F e}=boldsymbol{F} boldsymbol{e}^{2+}+boldsymbol{2} boldsymbol{e}^{-} ; quad boldsymbol{E}^{o}=+mathbf{0 . 4 1} mathbf{V} )
Then the standard e.m.f. of the cell with
the reaction ( boldsymbol{F e}^{2+}+boldsymbol{Z n} rightarrow boldsymbol{Z n}^{2+}+boldsymbol{F e} )
is?
A . ( -0.35 v )
B. ( +0.35 v )
c. ( +1.17 v )
D. ( -1.17 v )
12
1373 What two metals are often used in
electrochemical cells?
A. zinc and copper
B. Zinc and sulfur
c. carbon and copper
D. zinc and carbon
E. Sulfur and copper
12
1374 Cadmium amalgam is prepared by
electrolysis of a solution of ( C d C l_{2} ) using a mercury cathode. Find how long a current of 5 ampere should be passed in order to prepare ( 12 % C d-H g )
amalgam on a cathode of ( 2 g ) mercury.
At. mass of ( C d=112.40 )
12
1375 The standard reduction potential at
( 25^{circ} mathrm{C} ) of the reaction ( 2 H_{2} O+2 e^{-} rightleftharpoons )
( H_{2}+2 stackrel{ominus}{O} H ) is ( -0.8277 mathrm{V} . ) The
equilibrium constant for the reaction ( 2 H_{2} O rightleftharpoons H_{3} O^{oplus}+stackrel{ominus}{O} ) at ( 25^{circ} C ) is:
A ( cdot K_{w}=9.35 times 10^{-15} )
В. ( K_{w}=9.83 times 10^{-15} )
C . ( K_{w}=9.14 times 10^{-15} )
D. None of these
12
1376 Which substances are needed for iron
to rust?
A. Carbon dioxide and oxygen
B. Oxygen only
c. water and carbon dioxide
D. water and oxygen
12
1377 If a salt bridge is not used between two half cells, what happens to the voltage?
A. Drops to zero
B. Does not change
c. Increases gradually
D. Increases rapidly
12
1378 The electrolysis of molten NaOH
liberates ( 0_{2} ) at anode.
If true enter 1 , else enter 0 .
12
1379 ( K C l ) is used in salt bridge because:
A. it forms a good jelly with agar-agar
B. it is a strong electrolyte
c. it is a good conductor of electricity
D. the transference number of ( K^{+} ) and ( C l^{-} ) ions are almost equal
12
1380 ven in Column I with the items given in Column II.
Α. Λm
Q.51 Match the terms given in Column I with the
Column 1
Column II
1. Intensive property
2. Depends on number of
ions/volume
3. Extensive property
Increases with dilution
B.
Ecell
D
A
, Gcell
12
1381 For which cell e.m.f. is independent of
the concentrations of electrolytes used?
( mathbf{A} cdot F e|F e O(s)| K O H(a q)|N i O(s)| N i_{2} O_{3}(s) mid N i )
( mathbf{B} cdot P tleft(H_{2}right)|H C l| P tleft(C l_{2}right) )
( mathbf{c} cdot Z nleft|Z nleft(N O_{3}right)_{2}right|left|C u S O_{4}right| C u )
D. ( H g, H g C l_{2}left|K C l | A g N O_{3}right| A g )
12
1382 Q17. How can CuSo solution not be stored in an iron vessel?
27
12
1383 Which among the following metals is employed to provide cathodic protection to iron?
A. zinc
B. Nickel
( c . ) Tin
D. Lead
12
1384 The cell potential of ( mathbf{A} mathbf{g}|mathbf{A} mathbf{g} mathbf{B} mathbf{r}(mathbf{s})| mathbf{H} mathbf{B} mathbf{r}_{(0.02 mathrm{M})}left|mathbf{H}_{mathbf{2}(mathbf{0 . 5} mathrm{atm})}right| mathbf{P} mathbf{t}(mathbf{G} mathbf{i} )
is:
A . ( 0.26 v )
B. -0.26V
c. ( 0.16 v )
D . -0.16v
12
1385 For a cell reaction ( 2 H_{2}(g)+O_{2}(g) longrightarrow )
( 2 H_{2} O(l) ; triangle_{r} S_{298}^{circ}=-0.32 k J / K . ) What
is the value of ( triangle_{f} H_{298}^{circ}left(H_{2} O, lright) ? )
Given ( quad O_{2}(g)+4 H^{+}(a q .)+4 e^{-} longrightarrow )
( 2 H_{2} O(l) ; quad E^{0}=1.23 V )
A. ( -285.07 k J / ) mol
в. ( -570.14 mathrm{kJ} / mathrm{mol} )
c. ( 285.07 k J / ) mol
D. None of these
12
1386 Select correct statement.
A. In lead storage battery, galvanic cells are linked in series
B. Cathode and anode compartments are not separated in a battery as oxidizing agents and reducing agents both are solids
C. Recharging of storage battery is a non spontaneous process
D. All are correct statements
12
1387 Question 21. Why on dilution the Am of CH3COOH increases
drastically, while that of CH3COONa increases gradually?
12
1388 ( Z nleft|Z n^{2+}(a q)right|left|C u^{2+}(a q)right| C u . E^{o} ) for ( C u )
and ( Z n ) are 0.35 and -0.76
respectively:
Find EMF of cell (nearest integer) if
( Z n^{2+} ) and ( C u^{2+} ) are 1 M each.
12
1389 The specific conductance of a
( 0.1 N K C l ) solution at ( 23^{circ} C ) is
0.0112 oh ( m^{-1} c m^{-1} . ) The resistance of
the cell containing the solution at the
same temperature was found to be ( mathbf{5 5} ) ohm. The cell constant will be:
A. ( 0.142 mathrm{cm}^{-1} )
B. ( 0.918 mathrm{cm}^{-1} )
c. ( 1.12 mathrm{cm}^{-1} )
D. ( 0.616 mathrm{cm}^{-1} )
12
1390 Assertion
( left(H_{2}+O_{2}right) ) fuel cell gives a constant
voltage throughtout its life.
Reason In this fuel cell, ( H_{2} ) reacts with ( stackrel{ominus}{O H} ) ions, yet the over all ( [stackrel{ominus}{O} boldsymbol{H}] ) does not change.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
1391 Which of the following is an additive property?
A. conductance
B. Viscosity
c. Surface tension
D. None of these
12
1392 Which of the following has the highest oxidation potential?
A. ( N a )
в. ( A g )
c. ( A l )
D. ( Z ) n
12
1393 Same quantity of electricity being used to liberate iodine (at anode) and a metal (at
cathode). The mass of metal liberated at
cathode is 0.617 g and the liberated iodine completely reduced by ( 46.3 mathrm{ml} ) of ( 0.124 mathrm{M} ) sodium thiosulphate solution. What is
equivalent weight of metal?
A . 23 ( g )
в. ( 127 mathrm{g} )
c. ( 108 mathrm{g} )
D. 46
12
1394 In an electrochemical cell, cathode is:
A. always neutral
B. always positive
C. the electrode at which reduction takes place
D. always negative
12
1395 What is the difference between galvanic cell and electrolytic cell?
A. In galvanic cell, electrical energy is produced while in electrolytic cell electrical energy is consumed
B. In galvanic cell, anode is (-) ve while in electrolytic cell anode is ( (+) ) ve
c. In galvanic cell, cathode is ( (+) ) ve while in electrolytic cell anode is ( (-) v e )
D. All are correct
12
1396 If same quantity of electricity is passed
through three electrolytic cells
containing ( boldsymbol{F} boldsymbol{e} boldsymbol{S} boldsymbol{O}_{4}, boldsymbol{F} boldsymbol{e}_{2}left(boldsymbol{S} boldsymbol{O}_{4}right)_{3}, ) and
( boldsymbol{F} boldsymbol{e}left(boldsymbol{N} boldsymbol{O}_{3}right)_{3}, ) then:
This question has multiple correct options
A. the amount of iron deposited in ( F e S O_{4} ) and ( F e_{2}left(S O_{4}right)_{3} ) are equal
B. the amount of iron deposited in ( F e S O_{4} ) is 1.5 times of the amount of iron deposited in ( F eleft(N O_{3}right)_{3} )
C. the amount of iron deposited in ( F eleft(S O_{4}right)_{3} ) and
( F eleft(N O_{3}right)_{3} ) are equal
D. the same amount of gas is evolved in all three cases of the anode.
12
1397 Which of the following methods is employed to prevent rusting?
A. Annealing
B. Alloying
c. Enamelling
D. both (b) and (c)
12
1398 If the cell voltage is 1.23 V for the ( H_{2}-O_{2} )
fuel cell and for the
half cell :
( O_{2}+2 H_{2} O+4 e^{-} rightleftharpoons 4^{ominus} H )
( boldsymbol{E}^{ominus}=mathbf{0 . 4 0} boldsymbol{V}, ) then ( boldsymbol{E}^{ominus} ) for ( boldsymbol{2} boldsymbol{H}_{2} boldsymbol{O}+ )
( mathbf{2} e^{-} rightleftharpoons boldsymbol{H}_{2}+mathbf{2} stackrel{ominus}{O} boldsymbol{H} ) will be:
( mathbf{A} cdot 0.56 V )
в. ( 0.73 V )
c. ( 0.41 V )
D. ( 0.83 V )
12
1399 Q. 13 The quantity of charge required to obtain one mole of aluminium from
AL203 is ……….
(b) 6 F
(c) 3 F
(a) 1 F
(d) 2 F
.
12
1400 A secondary cell is one that:
A. can be recharged
B. can be recharged by passing current through it in the same direction
C. can be recharged by passing current through it in the opposite direction
D. can not be recharged
12
1401 Which of the following units is correctly
matched?
A. SI units of conductivity is ( S m^{-1} )
B. ( S I ) units of molar conductivity is ( S mathrm{cm}^{2} mathrm{mol}^{-1} )
c. ( S I ) unit of conductance is ( S^{-1} )
D. All of these
12
1402 The rusting of iron takes place as follows:
( mathbf{2} boldsymbol{H}^{oplus}+mathbf{2} e^{-}+frac{mathbf{1}}{mathbf{2}} boldsymbol{O}_{2} rightarrow )
( boldsymbol{H}_{2} boldsymbol{O}(boldsymbol{l}) ; boldsymbol{E}^{ominus}=+mathbf{1} cdot boldsymbol{2} boldsymbol{3} boldsymbol{V} )
( boldsymbol{F} boldsymbol{e}^{2+}(boldsymbol{a} boldsymbol{q})+boldsymbol{2} boldsymbol{e}^{-} rightarrow boldsymbol{F} boldsymbol{e}(s) ; boldsymbol{E}^{ominus}= )
( -0.44 V )
Calculate ( Delta G^{ominus} ) for the net process.
B. ( -152 k J ) mol( ^{-1} )
c. ( -76 k J ) mol ( ^{-1} )
D. – ( 161 k J ) mol ( ^{-1} )
12
1403 The specific conductance of a saturated
solution of silver bromide is ( kappa mathbf{S} mathrm{cm}^{-1} )
The limiting ionic conductivity of
( A g^{+} ) and ( B r^{-} ) ions are ( x ) and ( y )
respectively. The solubility of silver bromide in ( mathrm{gL}^{-1} ) is:
[molar mass of ( mathrm{AgBr}=188 )
A. ( frac{kappa times 100}{x-y} )
B. ( frac{kappa}{x+y} times 188 )
c. ( frac{kappa times 1000 times 188}{x+y} )
D. ( frac{x times y}{kappa} times frac{1000}{188} )
12
1404 At what ( frac{left[boldsymbol{B r}^{+}right]}{sqrt{left[boldsymbol{C O}_{3}^{2-}right]}} ) does the following
cell have its reaction at equilibrium? ( boldsymbol{A} boldsymbol{g}(boldsymbol{s})left|boldsymbol{A} boldsymbol{g}_{2} boldsymbol{C} boldsymbol{O}_{3}(boldsymbol{s})right| boldsymbol{N} boldsymbol{a}_{2} boldsymbol{C O}_{3}(boldsymbol{a} boldsymbol{q}) | boldsymbol{K} boldsymbol{B} boldsymbol{r} )
( boldsymbol{K}_{s p}=mathbf{8} times mathbf{1 0}^{-12} ) for ( boldsymbol{A} boldsymbol{g}_{2} boldsymbol{C} boldsymbol{O}_{2} ) and
( boldsymbol{K}_{s p}=mathbf{4} times mathbf{1 0}^{-13} ) for AgBr.
A. ( sqrt{1} times 10^{-7} )
B . ( sqrt{2} times 10^{-7} )
c. ( sqrt{3} times 10^{-7} )
D. ( sqrt{4} times 10^{-7} )
12
1405 If the molar conductance values of
( C a^{2+} ) and ( C l^{-} ) at infinite dilution are
respectively ( 118.88 times ) ( 10^{-4} m^{2} ) mho mol ( ^{-1} ) and ( 77.33 times )
( 10^{-4} m^{2} ) mho mho ( ^{-1} ) then that of ( C a C l_{2} )
is:
A . ( 118.88 times 10^{-4} )
B . ( 154.66 times 10^{-4} )
c. ( 273.54 times 10^{-4} )
D. ( 196.21 times 10^{-4} )
12
1406 What happens when the current
passing through the circuit is too
weak?
A. The filament does not get heated sufficiently and the bulb does not glow.
B. The filament gets heated but the bulb does not glow
c. The filament does not get heated but the bulb glows
D. The filament gets heated and the bulb glows
12
1407 The internal resistance of a dry cell is of the order of:
A. 0.2 to 0.4 ohm.
B. 1 to 1.4 Ohm.
c. 2 to 5 ohm.
D. 1 to 15 Ohm.
12
1408 Which of the following statements are
correct regarding the galvanic cell?
This question has multiple correct options
A. A reaction is spontaneous from left to right if ( E_{text {cell}}>0 )
B. A reaction occurs from right to left if ( E_{text {cell}}<0 )
C. If the system is at equilibrium no net reaction occurs
D. ( E_{text {cell}} ) is temperature-independent
12
1409 By virtue of Faradays second law of electrolysis, the electrochemical equivalent of the two metals liberated at the electrodes has
the same ratio as that of their:
A. Atomic masse
B. Molecular masses
c. Equivalent masses
D. All the above
12
1410 The graph of ( sqrt{C} ) vs ( Lambda_{m} ) for an aqueous solution of which substance is not
obtained as a straight line?
A. ( H C l )
в. ( N a O H )
c. ( N a C l )
D. ( H C N )
12
1411 The reduction potential of a hydrogen electrode at ( p H 10 ) at ( 298 K ) is ( :(P= )
1 ( (a t m) )
A. 0.51 volt
B. 0 volt
c. 0.591 volt
D. 0.059 volt
12
1412 Which of the following are
concentration cells?
This question has multiple correct options
( mathbf{A} cdot P tleft|H_{2}(g)right| H C lleft|H_{2}(g)right| P t )
B. ( P t: P t: / begin{array}{l}H C l / / H C l / H_{2}: P t \ left(P^{H}=4right)^{prime} /left(P^{H}=2right)end{array} )
( mathbf{c} . A g / A g C l / / A g B r / A g )
( (1 M) quad 1 M )
( mathbf{D} cdot A g|A g C l| C_{c_{1}}^{-}(a q)|| B_{c_{2}}^{-}(a q)|A g B r| A g )
12
1413 In a hydrogen-oxygen fuel cell, combustion of hydrogen occurs to:
A. generate heat
B. create potential difference between the two electrodes
c. produce high purity water
D. remove absorbed oxygen from electrode surfaces
12
1414 The conductivity of saturated solution of ( B a S O_{4} ) is ( 3.06 times 10^{-6} ) mho ( c m^{-1} )
and its equivalent conductance 1.53 ( operatorname{mhocm}^{2} e q^{-1} . ) The ( K_{s p} ) for ( B a S O_{4} ) will
be:
A ( cdot 10^{3} M )
В. ( 4 times 10^{6} M )
c. ( 10^{-3} M )
D. ( 4 times 10^{-6} M )
12
1415 Find out the volume of gasses evolved by
passing 0.965 A current for 1 hr through
an aqueous solution of ( C H_{3} C O O N a ) at
( 25^{0} C ) and 1 atm:
A . ( 0.036 L )
B. 1.76 L
c. ( 0.072 mathrm{L} )
D. 1.12 L
12
1416 Flow of current though electrolyte solution is due to migration of :
A. Ions
B. Electrons
c. Protons
D. Nucle
12
1417 Anode in the galvanic cell is :
A. Negative electrode
B. Positive electrode
c. Neutral electrode
D. None of the above
12
1418 The factors that promote electro
chemical corrosion are
A. the nature of the impurity metal with which the metal under consideration is associated.
B. the concentration of ( O_{2} ) in contact with the surface of
the metal.
C. highly conducting solutions.
D. all the above.
12
1419 A current liberates ( 0.50 g ) of hydrogen in
2 hours. The weight of copper(At.wt. ( = )
63.5 ) deposited at the same time by the
same current through copper sulphate solution is:
( mathbf{A} cdot 63.5 g )
в. ( 31.8 g )
c. ( 15.9 g )
D. ( 15.5 g )
12
1420 Match the following and choose the
correct option given below.
Compound / Type
A. Dry ice
I. Anti-knocking compound
B. ( quad ) II. Electronic diode or triode Semiconductor
C. Solder
III. Joining circuits
IV. Refrigerant for preserving
D. TEL ( quad ) food
A. ( A-I, B-11, C-1 V, D-111 )
B. ( A-11, B-111, C-1, D-1 V )
C. ( A-I V, B-I I I, C-11, D-1 )
D. ( A-I V, B-11, C-111, D-1 )
12
1421 ulatur
below find out the strongest reducing agent.
(d) Mn2+
(c) CM3+
. 8 Using the data given below find out the strong
Eczo-/Cr3+ = 1.33V; E ®Cl2/cl” = 1.30V
E®Mnoz /Mn2+ = 1.51V; EⓇCr3+/Cr = -0.74V
(a) CI
(6) Cr
Thinking Process
m includes concept of electrochemical series and standard reduction
potential of the metal.
Higher the negative value of standard reduction potential, strongest will be the reducing
agent
As value of SRP increases from negative to positive value nature of species changes from
reducing to oxidising nature.
12
1422 The magnitude of charge present on one azide ion in coulombs is:
( mathbf{A} cdot 96500 )
B . ( 4.8 times 10^{19} )
c. ( 4.8 times 10^{-19} )
D. ( 1.6 times 10^{-19} )
12
1423 The time required to produce ( 2 mathrm{F} ) of electricity with a current of 2.5 amperes is:
A. 21.44
B. 1200 min
c. 50000 s
D. 1.5 ( h )
12
1424 A cell with two electrodes, one of grey
tin and the other white tin, both dipped
in solution of ( left(N H_{4}right)_{2} S n C l_{6} ) showed
zero e.m.f. at ( 18^{circ} mathrm{C} ). What conclusion may
be drawn from this?
A. The e.m.f. developed at the electrode-solution phase boundary cancels the normal e.m.f.
B. Grey tin being non-metallic ceases to provide a reversible electrode reaction
C. Electrode surface develops a protective layer and the cell develops a very large internal resistance
D. The Gibbs energy change of the cell becomes zero
12
1425 (a) An organic compound (A) of
molecular formula ( C_{2} H_{4} O ) is prepared
by the reduction of compound (B) of
molecular formula ( C_{2} H_{3} N ) dissolved in
ether, with ( S n C l_{2} ) and ( H C l . ) Compound
(A) reduces Tollen’s reagent. When a
drop of conc. ( boldsymbol{H}_{2} boldsymbol{S} boldsymbol{O}_{4} ) is added to
compound (A), it polymerises to give a cyclic compound
(C). Identify (A), (B) and (C). Explain the reactions?
(b) Ionic conductance at infinite dilution of ( A l^{3+} ) and ( S O_{4}^{2-} ) are 189 ohm ( ^{-1} mathrm{cm}^{2} ) gm.equiv ( ^{-1} ) and
160 ohm ( ^{-1} mathrm{cm}^{2} ) gm.equiv ( ^{-1} ). Calculate
equivalent and molar conductance of the electrolytes at infinite dilution?
12
1426 At equilibrium, if ( boldsymbol{K}_{boldsymbol{p}}=mathbf{1}, ) then:
( mathbf{A} cdot Delta G^{o}>1 )
В. ( Delta G^{o}<1 )
c. ( Delta G^{o}=0 )
D. ( Delta G^{o}=1 )
12
1427 Corrosion can be prevented by using 12
1428 ( boldsymbol{P t}left|left(boldsymbol{H}_{2}right)right| boldsymbol{p} boldsymbol{H}=boldsymbol{2} | boldsymbol{p} boldsymbol{H}=boldsymbol{3} midleft(boldsymbol{H}_{2}right) boldsymbol{P} boldsymbol{t} . ) The
cell reaction for the given cell is :
A. spontaneous
B. non-spontaneous
c. equilibrium
D. None of the above
12
1429 Sonal has dropped her golden ring in
( mathrm{CuSO}_{4}, ) solution. Does she need to
worry? ( E_{A u^{3+} mid A u}^{o}=1.50 V, E_{C u^{2+} mid C u} V )
12
1430 The change in potential of the half-cell ( C u^{2+} / C u, ) when aqueous ( C u^{2+} )
solution is diluted 100 times at ( 298 K ? )
( left[frac{2.303 R T}{F}=0.06right] )
A. Increases by ( 120 mathrm{mV} )
B. Decreases by ( 120 mathrm{mV} )
c. Increases by ( 60 mathrm{mV} )
D. Decreases by ( 60 mathrm{mV} )
E. No change
12
1431 Balance the reaction of copper sulphide
with dilute hydrochloric acid.
( mathbf{A} cdot C u_{2} S+2 H C l rightarrow 2 C u C l+H_{2} S )
B ( cdot C u_{2} S+H C l rightarrow C u C l+H_{2} S )
( mathbf{c} cdot C u_{2} S+H C l rightarrow C u C l_{2}+H_{2}+S )
D. ( 2 C u_{2} S+2 H C l rightarrow 2 C u C l_{2}+S_{2}+H_{2} S )
12
1432 Copy and complete the following table which refers to two practical applications of electrolysis.
Anode Electrolyte
silver

Solution of plating a potassium spoo argentocya
Purificati of copper

12
1433 Molar conductivities at infinite dilution
of ( N a C l, H C l ) and ( C H_{3} C O O N a ) are
126.4,425.9 and ( 91.0 mathrm{Scm}^{2} ) mol ( ^{-1} )
respectively. Molar conductivity for
( boldsymbol{C H}_{3} boldsymbol{C O O H} ) will be:
12
1434 The number of electrons required for deposition of one mole of copper on the
cathode during the electrolysis of CuSO ( _{4} )
is:
B . 1.2×10 ( ^{2} )
c. ( 4.8 times 10^{24} )
D. 3×10 ( ^{23} )
12
1435 Approximate ( K_{c} ) for the reaction at
( 25^{circ} C ) will be:
( boldsymbol{Z} boldsymbol{n}(boldsymbol{s})+boldsymbol{C u}^{2+}(boldsymbol{a q})=boldsymbol{Z} boldsymbol{n}^{3+}(boldsymbol{a q})+ )
( boldsymbol{C u}(boldsymbol{s}) )
( boldsymbol{E}_{Z n^{2+} / Z n}^{o}=-mathbf{0 . 7 6} boldsymbol{V} boldsymbol{E}_{C u / C u^{2+}}^{o}= )
( -mathbf{0 . 3 4} V )
( mathbf{A} cdot 10^{11} )
B. ( 10^{3} )
( mathbf{c} cdot 10^{18} )
D. ( 10^{14} )
12
1436 (a) Define molar conductivity of a solution and explain how molar
conductivity changes which change in concentration of solution for a weak and
a strong electrolyte?
(b) The resistance of a conductivity cell
containing ( 0.001 M ) KCl solution at 298
Kis ( 1500 Omega ). What is the cell constant if
the conductivity of ( 0.001 mathrm{M} ) KCl solution
at ( 298 mathrm{K} ) is ( 0.146 times 10^{-3} mathrm{S} mathrm{cm}^{-1} ) ?
12
1437 10g fairly concentrated solution of
( boldsymbol{C u} boldsymbol{S O}_{4} ) is electrolysed using ( mathbf{0 . 0 1} )
faraday of electricity. The mass of resulting solution is :
A. ( 9.6025 mathrm{g} )
B. ( 10.6005 mathrm{g} )
c. ( 6.6025 mathrm{g} )
D. None of these
12
1438 Which modifications are necessary to
determine resistance of solutions by usual method of conductance
measurement?

This question has multiple correct options
A. A.c. should be used
B. A conductivity cell is used
c. Galvanometer is replaced by headphone or magic eye arrangement
D. None of the above

12
1439 ( Delta H^{ominus} ) for the cell reaction assuming
that these quantities remain
unchanged in the range ( 15^{circ} C ) to ( 35^{circ} mathrm{C} ) is:
A. ( -99.97 k J mathrm{mol}^{-1} )
B. ( 99.97 k J ) mol ( ^{-1} )
( mathbf{c} .-9.99 k J mathrm{mol}^{-1} )
D. ( 9.99 mathrm{kJ} mathrm{mol}^{-1} )
12
1440 Question 7. Value of standard electrode potential for the oxidation of
Clions is more positive than that of water, even then in the electrolysis
of aqueous sodium chloride, why is cl oxidised at anode instead of
water?
12
1441 Actual efficiency of fuel cell is only around:
A. 60-70%
в. 20-30%
c. ( 100 % )
D. 30-40%
12
1442 What will be standard cell potential of galvanic cell with the following
reaction?
( boldsymbol{2} boldsymbol{C r}_{(s)}+boldsymbol{3} boldsymbol{C} boldsymbol{d}_{(a q)}^{2+} rightarrow boldsymbol{2} boldsymbol{C r}_{(a q)}^{3+}+boldsymbol{3} boldsymbol{C} boldsymbol{d}_{(s)} )
( left[text { Given: } boldsymbol{E}_{C r^{3+} / C r}^{o}=-mathbf{0 . 7 4 V} ) and right.
( boldsymbol{E}_{C d^{2+} / C d}^{o}=-mathbf{0 . 4 0 V} )
( mathbf{A} cdot 0.74 mathrm{v} )
B. ( 1.14 mathrm{V} )
c. ( 0.34 v )
D. ( -0.34 mathrm{v} )
12
1443 Assertion
The presence of ( C O_{2} ) in the air
accelerates corrosion.
Reason
( C O_{2} ) is a poisonous gas.
A. Both Assertion and Reason are correct and Reason is
the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
1444 Resistance of a conductivity cell filled with a solution of an electrolyte of concentration ( 0.1 M ) is 100 ohm. The
conductivity of this solution is ( 1.29 S m^{-1} . ) Resistance of the same cell
when filled with ( 0.2 ~ M ) of the same
solution is 520 ohm. The molar
conductivity of ( 0.02 M ) solution of the electrolyte will be:
A ( cdot 124 times 10^{-4} mathrm{S} mathrm{m}^{2} mathrm{mol}^{-1} )
В. ( 1240 times 10^{-4} mathrm{S} ) m ( ^{2} ) mol ( ^{-1} )
c. ( 1.24 times 10^{-4} ) S ( m^{2} ) “nol ( ^{-1} )
D. ( 12.4 times 10^{-4} mathrm{S} mathrm{m}^{2} mathrm{mol}^{-} )
12
1445 Q. 45 Consider a cell given below
Cu Cu2+ || CL CL2., Pt
Write the reactions that occur at anode and cathode.
12
1446 A current of ( 9.65 A ) flowing for 10 minutes deposits ( 3.0 g ) of the metal which is monovalent.

The atomic mass of the metal is:
A . 10
B. 50
c. 30
D. 96.5

12
1447 The following are some statements about electrolysis:
I) Involves flow of electrons from anode to
cathode
II) Involves no chemical reaction at
electrodes
III) Oxidation occurs at anode and
reduction at cathode
IV) Anions migrate towards cathode
A. Only I and III are correct
B. Only I and II are correct
c. onlyı, I land III are correct
D. All are correct
12
1448 A resistance of ( 50 Omega ) is registered when
two electrodes are suspended into a beaker containing a dilute solution of a
strong electrolyte such that exactly half of the them are submerged into solution. If the solution is diluted by
adding pure water (negligible conductivity) so as to just completely submerge the electrodes, the new resistance offered by the solution would
be:
A . ( 50 Omega )
B. ( 100 Omega )
( c .25 Omega )
D. 200 ( Omega )
12
1449 A current of 2 amp when passed for 5 hours through a molten salt deposits ( 22.2 g ) of metal of atomic mass ( 177 . ) The
oxidation state of the metal in the
metal salt is:
A. +1
B. +2
( c cdot+3 )
D. +4
12
1450 Sulphuric acid is used in lead-acid storage batteries.
A. True
B. False
12
1451 The quantity of charge (in Faraday) required to reduce 96 g Mg from molten solution of ( mathrm{MgCl}_{2} ) is : 12
1452 In an electro chemical process, a salt
bridge is used
a) to maintain electro neutrality in each solution.
b) to complete the circuit so that current
can flow
c) as an oxidising agent
d) as a colour indicator
A. only a is correct
B. a and b are correct
c. a, b and care correct
D. all are incorrect
12
1453 In a salt solution, the flow of current is:
A. same as the direction of positive ions
B. opposite to the direction of negative ions
c. both a and b
D. opposite to the direction of positive ions
12
1454 Which of the following statement (s) differentiate between electrochemical
cell and electrolytic cell? This question has multiple correct options
A. Spontaneous or non-spontaneous nature of the chemical process.
B. Chemical reactions occurring at the electrodes
c. Positive and negative nature of anode
D. Dependence on Faraday’s law
12
1455 Lead accumulator is:
A. acid storage cell
B. alkali storage cell
( c cdot ) both
D. cant be predicted
12
1456 Q. 26 Molar conductivity of ionic solution depends on …….
(a) temperature
(b) distance between electrodes
(c) concentration of electrolytes in solution
(d) surface area of electrodes
12
1457 How much will the reduction potential of a hydrogen electrode change when its solution initially at ( mathrm{pH}=0 ) is neutralised to ( mathrm{pH}=7 ? )
A. Increases by ( 0.059 mathrm{V} )
B. Decreases by ( 0.059 mathrm{V} )
c. Increases by ( 0.41 V )
D. Decreases by ( 0.41 V )
12
1458 The weights of various ions liberated by passing the same current through different electrolytes are in the ratio of their:
A. Atomic weights
B. Equivalent weights
c. Molecular weights
D. Atomic numbers
12
1459 Question 15. In an aqueous solution how does specific conductivity of
electrolytes change with addition of water?
12
1460 The EMF of the cell :
( boldsymbol{P t}, boldsymbol{H}_{2}(boldsymbol{1} boldsymbol{a} boldsymbol{t m})left|boldsymbol{H}^{oplus}(boldsymbol{a} boldsymbol{q}) | boldsymbol{A} boldsymbol{g} boldsymbol{C l}right| boldsymbol{A} boldsymbol{g} ) is
0.27 and ( 0.26 mathrm{V} ) at ( 25^{circ} mathrm{C} ) and ( 35^{circ} mathrm{C} )
respectively. The posituve value of heat of the reaction occurring inside the cell
( operatorname{at} 25^{circ} Cleft(i n k J K^{-1}right) ) is: ( ( ) write your
answer to nearest integer)
12
1461 ( boldsymbol{E}^{o} ) value of ( boldsymbol{N} boldsymbol{i}^{2+} / boldsymbol{N} boldsymbol{i} ) is ( -mathbf{0 . 2 5} ) V and
( A g^{+} / A g ) is ( +0.80 V . ) If a cell is made by taking the two electrodes what is the feasibility of the reaction?
A. since ( E^{circ} ) value for the cell will be positive, redox reaction is feasible
B. since ( E^{o} ) value for the cell will be negative, redox reaction is not feasible
c. Ni cannot reduce ( A g^{+} ) to Ag hence reaction is not feasible
D. Ag can reduce ( N i^{2+} ) to Ni hence reaction is feasible
12
1462 The standard potential of the following
cells is ( 0.23 mathrm{V} ) at ( 15^{circ} mathrm{C} ) and ( 0.21 mathrm{V} ) at ( 35^{circ} mathrm{C} )
( boldsymbol{P t}left|boldsymbol{H}_{2}(boldsymbol{g})right| boldsymbol{H} boldsymbol{C l}(boldsymbol{a q})|boldsymbol{A} boldsymbol{g} boldsymbol{C l}(boldsymbol{s})| boldsymbol{A} boldsymbol{g}(boldsymbol{s}) )
Calculate ( -Delta H^{o} ) (in ( mathrm{kJ} ) ) for the cell
reaction by assuming that these quantities remain unchanged in the range ( 15^{circ} mathrm{C} ) to ( 35^{circ} mathrm{C}( ) to the nearest integer)
12
1463 Net reaction taking place when amalgam is in contact with Al foil:
A ( cdot 2 H_{2} O+O_{2} rightarrow 2 H_{2} O )
B. ( 4 A l+3 O_{2}+12 H^{oplus} rightarrow 4 A l^{3+}+6 H_{2} O )
c. ( A l+O_{2}+stackrel{delta}{O} rightarrowleft[A l(O H)_{4}right]^{ominus}+H_{2} O )
D. ( 4 A l+3 O_{2} rightarrow 2 A l_{2} O_{3} )
12
1464 The EMF of a galvanic cell is determined
by using a:
A. voltmeter
B. potentiometer
c. coulometer
D. ammeter
12
1465 Assertion: In a galvanic cell, the half-cel with higher reduction potential provides a reducing agent Reason: Easily reducible substances are good oxidants.
A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true but Reason is not the correct explanation of Assertion
c. Assertion is true but Reason is false
D. Assertion is false but Reason is true
E. Both Assertion and Reason are false
12
1466 The standard electrode potential of Cu/Cu
( ^{+2} ) electrode is ( 0.336 . ) It corresponds to
the reaction:
A. ( C u rightarrow C u^{+2}+2 e^{-} )
В ( cdot frac{1}{2} C u^{+2}+e^{-} rightarrow frac{1}{2} C u )
( mathrm{c} cdot mathrm{Cu}^{+2}+2 e^{-} rightarrow mathrm{Cu} )
D. ( 2 C u^{+} rightarrow C u+2 e^{-} )
12
1467 Total volume of gases evolved at STP
when ( 36 g ) of ( H_{2} O ) are completely
electrolyzed between platinum electrodes:
A. 22.4 litt
B. 44.8 litt
c. 33.6 litt
D. 67.2 lit
12
1468 During the charging of lead accumulator battery voltage varies from:
( mathbf{A} cdot 2 cdot 15 vee ) to ( 1.88 mathrm{v} )
в. 1.88 V to 2.0 v
c. ( 1.88 vee ) to 2.15 v
D. does not change
12
1469 Assertion
( E_{c e l l}^{0} ) is negative for electrolytic cell.
Reason
( triangle G^{0} ) is positive for electrolytic cell.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
1470 Given below are the half-cell reactions:
( M n^{2+}+2 e^{-} rightarrow M n ; E^{o}=-1.18 V )
( mathbf{2}left(boldsymbol{M} boldsymbol{n}^{3+}+boldsymbol{e}^{-} rightarrow boldsymbol{M} boldsymbol{n}^{2+}right) ; boldsymbol{E}^{o}= )
( +1.51 V )
The ( boldsymbol{E}^{o} ) for ( boldsymbol{3} boldsymbol{M} boldsymbol{n}^{2+} rightarrow boldsymbol{M} boldsymbol{n}+boldsymbol{2} boldsymbol{M} boldsymbol{n}^{3+} )
will be:
A. ( -0.33 V ; ) the reaction will not occur
B. ( -0.33 V ; ) the reaction will occur
c. ( -2.69 V ); the reaction will not occur
D. ( -2.69 V ); the reaction will occur
12
1471 9.49 Why on dilution the A, of CH,COOH increases drastically, while that of
CH3COONa increases gradually?
12
1472 0.9 Use the data given in Q. 8 and find out which of the following is the
strongest oxidising agent?
(a) CI
(b) Mn2-
(c) Mno:
(d) Cra+
l
ite
12
1473 Calculate the equailibrium constant for
the reaction:
[
boldsymbol{C u}_{(s)}+boldsymbol{2} boldsymbol{A} boldsymbol{g}_{(a q)}^{+} longrightarrow boldsymbol{C u}_{(a q)}^{2+}+boldsymbol{2} boldsymbol{A} boldsymbol{g}_{(s)}
]
Given that ( : boldsymbol{E}_{A boldsymbol{g}^{+} / boldsymbol{A} boldsymbol{g}}^{0}= )
[
mathbf{0 . 8 0 V}, quad boldsymbol{E}_{mathbf{C u}^{2+} / mathbf{C u}}^{mathbf{0}}=mathbf{0 . 3 4} boldsymbol{V}
]
12
1474 Predict which of the following reactions would proceed spontaneously at ( 298 mathrm{K} ? )
Take ( boldsymbol{E}_{boldsymbol{F} e^{2+} / boldsymbol{F} e}^{boldsymbol{0}}=-mathbf{0 . 4 4} boldsymbol{V} )
This question has multiple correct options
A ( cdot operatorname{Co}(s)+F e^{2+}(a q) rightarrowleft(C o^{2+}(a q)+F e(s)right. )
[
E_{C o^{+2} / C o}^{ominus}=-0.28 V
]
B. ( C d^{2+}(a q)+F e(s) rightarrow C d(s)+F e^{2+}(a q) )
[
E_{C d^{2+} / C d}^{ominus}=0.4 V
]
c. ( C d(s)+C o^{2+}(a q) rightarrow C d^{2+}(a q)+C o(s) )
[
E_{F e^{2+} / F e}^{ominus}=-0.44 V
]
D. ( Z n^{2+}(a q)+H_{2} rightarrow Z n(s)+2 H^{oplus} )
[
E_{Z n^{2+} / Z n}^{ominus}=-0.76 V
]
12
1475 The molar conductances of HCl, NaCl and
( C H_{3} C O O N a ) are ( 426,12691 Omega^{-1} c m^{2} m o l^{-1} )
respectively. The molar conductances of
( C H_{3} C O O H ) is :
A ( cdot 561 Omega^{-1} mathrm{cm}^{2} mathrm{mol}^{-1} )
B. ( 391 Omega^{-1} c m^{2} ) mol ( ^{-1} )
c. ( 261 Omega^{-1} c m^{2} m o l^{-1} )
D. ( 612 Omega^{-1} c m^{2} m o l^{-1} )
12
1476 Standard electrode potential for ( mathrm{Fe} )
electrode are given as ( F e^{++}+2 e^{-} rightarrow F e )
( E^{0}=-0.44 V F e^{3+}+e^{-} rightarrow F e^{++} E^{0}= )
( +0.77 V F e^{++}, F e^{+++} ) and Fe block are
kept together then:
A ( cdotleft[F e^{+++}right] ) decreases
B . ( left[F e^{+++}right] ) increases
C ( cdotleft[F e^{++} F e^{+++}right] ) remains unchanged
D. ( left