# Structure Of Atom Questions

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

Question NoQuestionsClass
1With increase in distance from the
nucleus, energy of electron. increases
though velocity of electron decreases.
How do you account for this?
11
2Total number of orbitals present in the given stationary state for the principal quantum number having value of ( n=3 )
?
A . 9
B. 7
( c cdot 4 )
D. 6
11
3Which element with lowest atomic
number
( mathbf{A} cdot_{19} K )
В ( cdot_{24} C r )
( mathbf{c} cdot_{11} N a )
D・ ( _{29} C u )
11
4The difference between the angular momentum of two orbits of ( H e^{+2} ) is ( frac{2 h}{pi} )
The energy of an electron present in the higher orbit is -1.51 eV. Indentify the lower orbit.
A
B. 2
( c cdot 3 )
D. 4
11
5Radius of nucleus may be given as ( boldsymbol{R}_{N}=boldsymbol{R}_{0} boldsymbol{A}^{1 / 3}, ) where ( boldsymbol{A}= ) mass
number and ( R_{0}= ) constant. Calculate
the density of nucleus of an atom if ( boldsymbol{R}_{0}=mathbf{1 . 2} times mathbf{1 0}^{-mathbf{1 5}} )
11
6What are the possible of ( m_{5} ) when ( m_{1} )
have ( +1,+2,+3 ? )
11
7Non-directional orbital is:
( mathbf{A} cdot 3 s )
B . ( 4 f )
c. ( 4 d )
D. ( 4 p )
11
8Though there is only one electron in a hydrogen atom, the spectrum of hydrogen contains a number of lines. How do you explain this?11
9According to Bohr’s theory of hydrogen atom it can be concluded that the
radius of stable orbits is proportional to
( mathbf{A} cdot n^{2} )
B. ( frac{1}{n} )
( c )
D. ( frac{1}{n^{2}} )
11
10In isotones the atomic number and
mass numbers are:
A. same
B. different
c. equal
D. zero
11
11Calculate the accelerating potential that must be imparted to a proton beam to wavelength of ( 0.005 mathrm{nm} )11
12The nuclei of which one of the following
pairs of nuclei are isotones:
( A cdot_{34} mathrm{Se}^{74},_{31} mathrm{Ga}^{71} )
B ( cdot_{38} mathrm{Sr}^{84},_{38} mathrm{Sr}^{86} )
C ( cdot_{42} mathrm{Mo}^{92},_{40} mathrm{Zr}^{9} )
D. ( _{20} mathrm{Ca}_{2}^{40},_{16} mathrm{S}^{32} )
11
13What the significance of negative electronic energy?11
1447. X-rays are produced by accelerating electrons by voltage
V and let they strike a metal of atomic number Z. The
highest frequency of X-rays produced is proportional to
(a) V
(b) Z
(c) (Z-1)
(d) (Z-1)
oto
11
11
15When electron jumps from ( mathrm{N} ) shell to shell, the energy is:
A. emitted
B. absorbed
c. reflected
D. cannot be predicted
11
16The uncertainties in the velocities of
two particles, ( A ) and ( B ) are 0.05 and
( 0.02 m s^{-1} ) respectively. The mass of ( B )
is five times to that of the mass of ( boldsymbol{A} ) What is the ratio of uncertainties ( frac{Delta x_{A}}{Delta x_{B}} ) in their positions?
A . 2
B. 0.25
( c cdot 4 )
( D )
11
17The mass number is the sum of the
number of protons and the number of
neutrons in an atom.

State whether the given statement is
true or false.
A. True
B. False

11
18Heisenberg Uncertainity principle is not valid for:
A. moving electron
B. motor car
c. stationary particles
D. both B and C
11
19The first use of quantum theory to explain the structure of atom was made
by:
A. Heisenbergg
B. Bohr
c. Planck
D. Einstein
11
20Q5. How many electrons in an atom can have n + 1 = 6?11
21What is the electron configuration of
( boldsymbol{V}^{2+} ? )
( mathbf{A} cdot[A r] 4 s^{2} 3 d^{3} )
B . ( [A r] 4 s^{1} 3 d^{4} )
( mathbf{c} cdot[A r] 3 d^{3} )
D ( cdot[A r] 4 s^{2} 3 d^{1} )
11
22Maximum frequency of emission is obtained for the transition:
( mathbf{A} cdot n=2 ) to ( n=1 )
B. ( n=6 ) to ( n=2 )
c. ( n=1 ) to ( n=2 )
D. ( n=2 ) to ( n=6 )
6
11
23Oxygen atom has an atomic mass of 16
u and eight neutrons in its nucleus. What is its atomic number?
( A cdot 4 )
B. 12
( c cdot 8 )
D. 6
11
24State True or False.
( mathrm{p}_{z} ) orbital is symmetrical about y-axis :
A. True
B. False
11
25The minimum energy required to overcome the attractive forces between
an electron and the surface of Ag metal
is ( 5.52 times 10^{-19} mathrm{J} ). What will be the
maximum kinetic energy of electron ejected out from Ag which is being exposed to UV-light of ( =360 mathrm{A} ? )
11
26Which of the following is the wrong statement?
A. ( O N F ) and ( O N O^{circ} ) are isoelectronic
B. ( C_{2} ) molecules is expected to exhibit diamagnetic behavior if ( s-p ) mixing is not operative
c. Ozone is diamagnetic gas
11
27If the kinetic energy of a particles is reduced to half, de broglie wave length becomes:
A. 2 times
B. ( frac{1}{sqrt{2}} ) times
c. 4 times
D. ( sqrt{2} ) times
11
28A neutral atom of fluorine has a mass
number of 19 and an atomic number of
9. How many neutrons does it have?
A . 10
B. 9
c. 19
D . 28
E. It is impossible to determine from the information given
11
2977. An electron and a photon have same wavelength. If pic
the momentum of electron and E the energy of photon
the magnitude of plE in SI unit is
(a) 3.0 x 108
(b) 3.33 x 10-9
(c) 9.1 x 10-31
(d) 6.64 x 10-34
11
30Let a light of wavelength ( lambda ) and intensity
( boldsymbol{I}^{prime} ) strikes a metal surface to emit ( boldsymbol{x} )
electrons per second. Average energy of each electron is ‘ ( y^{prime} ) unit. What will
happen to ‘ ( x ) ‘ and ‘ ( y ) ‘ when
(a) ( lambda ) is halved
(b) intensity ( I ) is doubled?
11
31Assertion
Atomic number is a more fundamental
property of an element than its atomic
mass.
Reason
Atomic number is equal to number of
protons in an atom.
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
11
32Thomson’s atomic model is also called:
A. water melon model
B. christmas pudding model
( c . ) both a and ( b )
D. none of above
11
33When alpha particles are used to bombard gold foil, most of the alpha
particles pass through undeflected. This result indicates that
most of the volume of a gold atom
consists of:
A. deuterons
B. neutrons
c. protons
D. unoccupied space
11
34Which particle among the following will have the smallest de Broglie wavelength, assuming that they have the same velocity?
A. Positron
B. Photon
c. ( alpha ) – particle
D. Neutron
11
35Calculate the orbital angular
momentum of the following orbitals:
(a) ( 3 p )
(b) ( 3 d )
(c) ( 3 s )
11
36The Bohr’s radius for the fifth orbit of
the hydrogen atom will be:
A . 0.529 A
B. 2.645 A
C. ( 13.225 mathrm{A} )
D. none of above
11
37“The exact path of an electron in ( 2 p ) orbital cannot be determined”, This statement is based upon:
A. Hund’s rule
B. Bohr’s’s rule
c. Uncertainty principle
D. Aufbau principal
11
38( _{6}^{14} boldsymbol{C} rightarrow_{7}^{14} boldsymbol{N}+boldsymbol{X} )
The above nuclear reaction is an
example of :
A. ( alpha ) decay
B ( cdot beta^{-} ) decay
( mathbf{c} cdot beta^{+} ) decay
D. Fusion
E . ( gamma ) decay
11
39How many Balmer spectral lines will be obtained when the excited electrons
return from 8th shell to 2nd shell?
A . 21
B. 4
c. 10
D. 15
11
40The species which are isoelectronic
with CO is:
A ( cdot C l )
в. ( O H^{-} )
( mathrm{c} cdot mathrm{CH}_{3}^{+} )
D. ( N_{2} )
11
41Angular momentum in an orbit is ( 3 n )
The value of ( n ) is :
( mathbf{A} cdot mathbf{1} )
B. 2
( c cdot 3 )
D. 4
11
42Total number of orbitals associated
with third shell will be
A .2
B. 4
( c cdot 9 )
D.
11
43An electron in hydrogen atom is excited to ‘N’ shell. What are the possible
transitions it can undergo ? Compare the energies of transitions.
11
44What will happen when an electron jumps from an excited energy state to a
more stable energy state in a hydrogen
atom?
A. Electromagnetic radiation is emitted by the atom
B. Electromagnetic radiation is absorbed by the atom
C. The atom becomes a positively charged ion
D. The atom becomes a negatively charged ion
E. The atom undergoes nuclear decay
11
45Which of the following is not a
characteristic of XX-rays?
A. The radiation can ionize gas
B. It causes ( Z n S ) to fluorescence
C. Deflected by electric and magnetic fields
D. Have wavelength shorter then ultraviolet rays
11
46The value of atomic number(z) is:11
47Calculate the number of neutrons in the
remaining atom after emission of an alpha particle from ( _{92}^{238} U ) atom.
11
48Which energy state of a doubly ionized
lithium ( left(L i^{++}right) ) has the same energy as
that of the ground state of hydrogen ( z=3, ) for lithium):
( mathbf{A} cdot n=1 )
B. ( n=2 )
( mathbf{c} cdot n=3 )
D. ( n=4 )
11
49Which of the following are isotones?
This question has multiple correct options
A. ( A r_{18}^{40} )
B. ( C a_{a_{0}^{2}}^{2} )
c. ( S c_{c 13}^{43} )
D. ( S c_{21}^{41} )
11
50If ( n=6, ) the correct sequence for filling of electrons will be:
A ( cdot n s rightarrow n p rightarrow(n-1) d rightarrow(n-2) f )
B . ( n s rightarrow(n-2) f rightarrow(n-1) d rightarrow n p )
C ( cdot n s rightarrow(n-1) d rightarrow(n-2) f rightarrow n p )
D. ( n s rightarrow(n-2) f rightarrow n p rightarrow(n-1) d )
11
51Which of the two orbitals have lower
energy among ( 4 s ) and ( 3 d ? )
11
52Show that the Balmer series occurs between ( 3647 dot{A} ) and ( 6563 hat{A} )
( left(boldsymbol{R}=mathbf{1} . mathbf{0} mathbf{9} mathbf{6} mathbf{8} times mathbf{1} mathbf{0}^{mathbf{7}} boldsymbol{m}^{-mathbf{1}}right) )
11
53( 0.25 g ) of an element ( M ) reacts with
excess fluorine to produce ( 0.547 g ) of the
hexafluoride ( M F_{6} . ) What is the
element?
A ( . C r )
в. ( M o )
( c cdot s )
D. ( T e )
11
54The velocity of an electron in a certain
Bohr orbit of H-atom bears the ratio
1: 275 to the velocity of light. The quantum number (n) of the orbit is :
( A cdot 3 )
B. 2
( c )
( D cdot 4 )
11
55Electromagnetic radiation of wavelength ( 242 mathrm{nm} ) is just sufficient to ionise the sodium atom. Calculate the
ionisation energy of sodium atom? ( (c= )
( 3 times 10^{8} mathrm{ms}^{-1}, mathrm{h}=6.626 times 10^{-34} mathrm{Js} )
A ( cdot 5.6 times 10^{-19} k J )
В . ( 6.9 times 10^{-18} k J )
c. ( 8.2 times 10^{-19} mathrm{J} )
D. 495 kJ
11
56Which element with lowest atomic
number follows rule (b)?
( A cdot 19^{k} )
B. 24 ( ^{c} )
( c cdot 11^{N a} )
D. ( 29^{c} )
11
57( boldsymbol{E}_{boldsymbol{n}}=-frac{mathbf{3 1 3 . 6}}{boldsymbol{n}^{2}}, ) if the value of ( boldsymbol{E}_{boldsymbol{i}}= )
-34.84 to which value ‘ ( n ) ‘ corresponds:
A . 2
B. 4
c. 1
D. 3
11
58have 4 to 8 electrons
in the outermost shell.
A. Non-metals
B. Metalss
c. Metalloids
D. Transition elements
11
59Multiple photoelectric effect
experiments were conducted by
applying a variety of visible wavelengths to a metal surface and
recording the electrical current
produced. Data from these experiments provided evidence for which of the following
claims?
A. Electromagnetic radiation exhibit wave-like characteristics.
B. Electromagnetic radiation exhibit particle-like characteristics.
C. Electrons have quantized energies in an atom.
D. Electrons behave like waves in an atom.
11
60Chemically, matter can be classified as
A. pure and impure substances
B. elements, compounds and mixtures
c. solids, liquids and gases
D. metals and non-metals
11
61Assertion
( beta ) -particles are deflected more than ( alpha ) particles in a given electric field.
Reason
Charge on ( alpha ) -particles is larger than on
( beta ) -particles.
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 the Reason is correct
11
62Suppose an electron is attracted towards the origin by a force ( frac{mathbf{k}}{mathbf{r}} ) where ( mathbf{k}^{prime} ) is a constant and ( mathbf{r}^{prime} ) is the distance of
the electron from the origin. By applying Bohr model to this system, the radius of the ( n^{text {th }} ) orbital of the electron is found to
be ( mathbf{r}_{mathbf{n}}^{text {‘ and the kinetic energy of the }} )
electron to be’ ( mathbf{T}_{mathbf{n}} . ) Then which of the
following is true?
A ( cdot mathrm{T}_{mathrm{n}} propto frac{1}{mathrm{n}}, mathrm{r}_{mathrm{n}} propto mathrm{n} )
B. ( mathrm{T}_{mathrm{n}} propto frac{1}{mathrm{n}}, mathrm{r}_{mathrm{n}} propto mathrm{n}^{2} )
( c cdot mathrm{T}_{mathrm{n}} propto frac{1}{mathrm{n}^{2}}, mathrm{r}_{mathrm{n}} propto mathrm{n}^{2} )
D. ( T_{n} ) independent of ( n, r_{n} propto n )
11
63What is the maximum number of
emission lines obtained when the
excited electron of a H atom in ( n=5 )
drops to the ground state?
A ( cdot 12 )
B. 15
( c cdot 2 )
D. 10
11
64Which of the following have identical value of e/m?
A. A proton & a neutron
B. A proton & a deuterium
c. Deutorium & an ( alpha ) -particle
D. An electron and ( gamma ) -rays
11
65Calculate no. of ions, atoms, protons,
electrons in ( 3 g C O_{3}^{2-} )
11
66( begin{array}{lll}text { Element } & text { Reaction with water } & triangle boldsymbol{T}left(^{circ} boldsymbol{C}right) \ mathrm{A} & text { small bubbles formed } & -2 \ mathrm{B} & text { vigorous bubbling } & +10 \ mathrm{C} & text { dissolves, no bubbles } & 0 \ mathrm{D} & text { small bubbles formed } & 0end{array} ) Which electron configuration would
match the laboratory data for Element
( mathrm{B} ? )
( mathbf{A} cdot[N e] 3 s^{2} )
( mathbf{B} cdot[X e] 6 s^{2} )
( mathbf{C} cdot[A r] 4 s^{2} 3 d^{10} )
D. ( [N e] 3 s^{2} 3 p^{3} )
11
67The electron is present in the N shell in H-atom. When energy is lost, spectral line may be observed in ( ldots ldots . . ) region.
( A ). infra-red
B. visible
c. ultra-violet
D. any of these
11
68Statement I: ( _{6}^{14} C ) and ( _{6}^{12} C ) are isomers of the element carbon.

Statement II: Isomers contain the same
number of protons but a different number of neutrons
A. Both Statement I and Statement II are correct and Statement II is the correct explanation of Statement
B. Both Statement I and Statement II are correct, but Statement II is not the correct explanation of Statement I.
c. Statement I is correct, but Statement II is incorrect
D. Both Statement I and Statement II are incorrect

11
69The ionising power of ( alpha, beta ) and ( gamma ) -rays is in the decreasing order:
A ( . alpha>beta>gamma )
в. ( beta>alpha>gamma )
c. ( gamma>alpha>beta )
D. ( beta>gamma>alpha )
11
70Splitting of spectral lines in electric
field is called stark effect.
A. True
B. False
11
71A potential difference of ( 20 mathrm{KV} ) is applied across an X-ray tube. Find the minimum wavelength of X-ray generated.11
72A mono-electronic species in energy
level with energy X was provided with
excess of energy so that it jumps to higher energy level with energy Y. If it
can emit 6 wavelengths originated from all possible transition between these groups levels, then which of the
following relation is correct?
(Here ( n ) is the principle quantum of
energy level ( X ) )
A ( . X / Y=(n-1)^{2} )
B. ( X / Y=1+3 / N )
c. ( sqrt{(X / Y)}=1+3 / N )
D. ( X / Y=N / 6 )
11
73Q4. What is the difference between the notations I and L?11
74J J Thomson Model could not able to
explain the following?
A. Stability of Atom
B. electrical neutrality of atom
c. stability of nuclcus
D. all of these
11
75Assertion
Energy of electron in 1st orbit of ( boldsymbol{H} boldsymbol{e}^{+} ) is
more than that in Hydrogen atom.
Reason
Nuclear charge is more in ( H e^{+} ) than in
Hydrogen.
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
11
76By changing the metal electrodes and gas inside the cathode ray tube,
A. The same particles-electrons were produced.
B. The same particles-neutrons were produced.
c. The same particles-protons were produced
D. New particles were produced
11
77Plum Pudding Model of the Atom was given by:
A. Thomson
B. Rutherford
c. Bohr
11
78The uncertainty in position of an electron ( left(boldsymbol{m}=mathbf{9 . 1} times mathbf{1 0}^{-mathbf{2 8}} mathbf{g m}right) ) moving
with a velocity ( 3 times 10^{4} mathrm{cm} / mathrm{s} ) accurate
upto ( 0.001 % ) will be:
( A . quad 3.84 mathrm{cm} )
B. 1.92 ( mathrm{cm} )
c. ( 7.68 mathrm{cm} )
D. 5.76 cm
11
79The work function of a metal is 4 eV. If
light of frequency ( 2.3 times 10^{15} mathrm{Hz} ) is
incident on metal surface, then:
A. no photoelectron will be ejected
B. 2 photoelectron of zero kinetic energy are ejected
C. 1 photoelectron of zero kinetic energy is ejected it
D. 1 photoelectron is ejected, which required the stopping potential of 5.52 volt
11
80Which atom would require the shortest
wavelength photon to remove a single
electron?
A. ( M g )
B. ( S ) i
( c . P )
D.
E . ( C l )
11
81The quantum number n of the state
finally populated in ( mathbf{H e}^{+} ) ions is:
( A cdot 2 )
B. 3
( c cdot 4 )
D. 5
11
82The correct set of quantum numbers for ( t )
he last electron of ( N a^{+} ) is :
( mathbf{A} cdot 3,0,0,-frac{1}{2} )
B. ( 3,1,0,+frac{1}{2} )
( mathbf{c} cdot 3,1,1,+frac{1}{2} )
D. ( 2,1,0,-frac{1}{2} )
11
83Which of the following sets of ions represents a collection of isoelectronic
species?
A ( cdot N^{3}, O^{3}, F^{-}, S^{2-} )
B . ( L i^{+}, N a^{+}, M g^{2+}, C a^{2+} )
C ( cdot K^{+}, C l^{-}, C a^{2+}, S c^{3+} )
D. ( B a^{2+}, S r^{2+}, K^{+}, C a^{2+} )
11
84Determine uncertainty in the position of an electron moving with a velocity 300
( mathrm{m} cdot mathrm{sec}^{-1} ) accurate up to ( 0.001 % )
( left[h=6.63 times 10^{-34} mathrm{J} . mathrm{s} ) and mass of right.
electron ( =9.1 times 10^{-31} mathrm{kg} )
A ( cdot 1.92 times 10^{-2} mathrm{m} )
в. ( 1.5 times 10^{-2} mathrm{m} )
C. ( 2.5 times 10^{-2} m )
D. ( 2.5 times 10^{-3} mathrm{m} )
11
85If there are three possible values
( (-1 / 2,0,+1 / 2) ) for the spin quantum,
then electronic configuration of ( boldsymbol{K}(mathbf{1 9}) )
will be:
A ( cdot 1 s^{3}, 2 s^{3} 2 p^{9}, 3 s^{3} 3 p^{text {th }} )
B . ( 1 s^{2}, 2 s^{2} 2 p^{6}, 3 s^{2} 3 p^{6}, 4 s^{1} )
C ( cdot 1 s^{2}, 2 s^{2} 2 p^{9}, 3 s^{2} 3 p^{4} )
D. None of these
11
86Who is the discoverer of Proton?
A. J. J. Thomson
c. Ernest Rutherford
D. None of the above
11
87State whether the given statement is true
or false:
Elements with an odd number of
protons usually have only one or two stable isotopes.
A. True
B. False
11
88Deduce the condition when the De-
Broglie wavelength associated with an
electron would be equal to that
associated with a proton if a proton is 1836 times heavier than an electron
11
89Which of the following values corresponds to the value of energy required to remove the second electron
from the ground state of helium atom?
( mathbf{A} cdot-27.2 e V )
B. ( -13.6 e V )
c. ( -6.8 e V )
D. ( -54.4 e V )
11
90The maximum kinetic energy of
photoelectrons ejected from a metal, when it is irradiated with radiation of
frequency ( 2 times 10^{14} s^{-1} ) is ( 6.63 times 10^{-20} J )
Find the threshold frequency of the
metal.
11
91The work function for caesium atom is
1.9 eV. Calculate
(a) threshold
wavelength and
with a wavelength of 500 nm. Calculate the kinetic energy and the velocity of
the ejected electron.
11
92An electron beam can undergo
diffraction by crystals. Through what potential should a beam of electrons be
accelerated so that its wavelength becomes equal to 1.54 A?
A. 13.6 volt
B . 1.54 volt
c. 1 volt
D. 63.44 volt
11
93The increase order for the value of ( e / m ) (charge to mass ratio) for electron ( (e) ) proton ( (p) ; ) neutron ( (n) ) and alpha particle ( (alpha) ) is:
A ( cdot e<p<n<alpha )
в. ( n<p<e<alpha )
c. ( n<p<alpha<e )
D. ( n<alpha<p<e )
11
94Choose the correct statement for proton.
( mathbf{A} cdot ) It is a nucleus of deuterium
B. It is an ionized hydrogen atom
C. It is an ionized hydrogen molecule
D. It is an ( alpha ) – particle
11
95If the momentum of a particle which
has a de Broglie wave length of 10 nm is ( A times 10^{-26} mathrm{ms}^{-1} ) then nearest integer
value of ( A ) is :
11
96The line spectra of two elements are
different because:
A. the elements do not have the same number of
neutrons
B. they have different mass numbers
C. their outermost electrons are at different energy levels
D. all of the above
11
97In Thomson’s model of the atom, which
of the following statements are correct?
(i) The mass of the atom is assumed to
be uniformly distributed over the atom.
(ii) The positive charge is assumed to be uniformly distributed over the atom.
(iii) The electrons are uniformly distributed in the positively charged
sphere
(iv) The electrons attract each other to
stabilize the atom.
A. (i), (ii) and (iii)
B. (i) and (iii)
c. (i) and (iv)
D. (i), (iii) and (iv)
11
98Thomson atomic theory proved that the stream in cathode ray tube is made up of small particles which is piece of the atom and is :
A. neutral
B. negatively chargedd
c. positively charged
D. both A and B
11
shown for ( s ) -orbital. The curve is:
A . ( 1 s )
B . ( 2 s )
( c .3 s )
D. ( 4 s )
11
100The mass of an atom of carbon is:
A. ( 1 g )
В. ( 1.99 times 10^{-23} g )
c. ( 1 / 12 g )
D. ( 1.99 times 10^{23} g )
11
101Which of the following are isobars?
A ( . ) Ce, ( mathrm{Se} )
B. Fe, Se
( mathrm{c} cdot mathrm{Fe}, mathrm{Ce} )
D. Ce, Ni
11
102Minimum photocurrent which must be passed through the circuit
A . 2.88
B. 1.44
( c cdot 2.08 )
D. 0.64
11
103In classical theory, i.e, in Rutherford
atomic model path of the electron will
be
A. Circular
B. Straight
c. Parabolic
D. Spiral
11
104Which one of the following does not
contains electrons in ( 4 s ) subshells?
Given that : Atomic numbers: ( boldsymbol{T} boldsymbol{i}= )
( mathbf{2 2}, boldsymbol{V}=mathbf{2 3}, boldsymbol{C r}=mathbf{2 4}, boldsymbol{M} boldsymbol{n}=mathbf{2 5} )
A ( cdot T i )
B. ( V^{text {t }} )
( c cdot C r^{+} )
D. ( M n^{+} )
11
105What is the difference in number of
neutrons in Protium and Deuterium?
( mathbf{A} cdot mathbf{1} )
B. 2
( c cdot 3 )
( D )
11
106Which of the following conditions is incorrect for a well behaved wave
function ( (mathbf{Psi}) ? )
A. ( Psi ) must be finite
B. Psi must be single valued
c. ( Psi ) must be infinite
D. ( Psi ) must be continuous
11
107If K.E. of an electron, ( alpha ) -particle and a proton are represented by
( boldsymbol{E}_{1}, boldsymbol{E}_{2} ) and ( boldsymbol{E}_{3} ) respectively, (provided all these have same de Broglie wavelength) then:
A. ( E_{1}=E_{2}=E_{3} )
B . ( E_{1}>E_{2}>E_{3} )
c. ( E_{1}>E_{3}>E_{2} )
D. ( E_{2}>E_{3}>E_{1} )
11
108Assertion
Bohr had to postulate that the electrons in stationary orbits around the nucleus
Reason
According to classical physics all moving electrons radiate.
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
11
109Orbit is a region of space around the nucleus where the probability of finding an electron is maximum.
A. True
B. False
11
110An element belonging to 3d series of
modern periodic table has spin magnetic moment =5.92 B.M.in +3 oxidation state. Determine the atomic
number of element.
11
11125. The work function of a metal is Wand 2 is the wavelength
of the incident radiation. There is no emission of
photoelectrons when
(a) 2 > hc/W
(b) 2 = hc/W
(c) i< hc/W
(d) 2 shc/W
2011
11
when the electron falls from ( n=4 ) to
( boldsymbol{n}=mathbf{1} ) in a hydrogen atom will be (Given
ionisation energy of ( boldsymbol{H}=mathbf{2 . 1 8} times )
( 10^{-18} J a t o m^{-1} ) and ( h=6.626 times )
( left.10^{-34} J-sright) )
( mathbf{A} cdot 1.54 times 10^{15} s^{-1} )
В. ( 1.03 times 10^{15} s^{-1} )
C ( .3 .08 times 10^{15} s^{-1} )
D. ( 2 times 10^{15} s^{-1} )
11
113Rutherford’s atomic model does not say
anything about the arrangements of electron in an atom
A. True
B. False
11
114The velocity of an electron in the first
Bohr orbit of a hydrogen atom is:
A . ( 3.08 times 10^{6} mathrm{m} / mathrm{s} )
B. ( 2.18 times 10^{6} mathrm{m} / mathrm{s} )
( mathbf{c} cdot 2.78 times 10^{6} m / s )
D. none of these
11
115Which one of the following has the
greatest mass?
A. Alpha particle
B. Beta particle
c. Neutron
D. Gamma ray
E . Positron
11
116The ground state energy of hydrogen
atom is ( -13.6 mathrm{eV} . ) The energy of second
excited state ( H e^{+} ) ion in eV is:
A . -6.04
B . -27.2
c. -54.4
D. – 3.
11
117Which of the following statements are
correct?
This question has multiple correct options
A. Electron density in ( X Y ) plane of ( 3 d_{x^{2}-y^{2}} ) orbital is zero.
B. Electron density in ( X Y ) plane of ( 3 d_{z^{2}} ) orbital is zero.
C. ( 2 s ) orbital has only one spherical node.
D. For ( 2 p_{z} ) orbital ( Y Z ) is the nodal plane.
11
According to Bohr, when electronjumps
from one shell to another:
This question has multiple correct options
A. if it gains energy, it moves away from the nucleus
B. when it gains energy it moves towards the nucleus
C. it emits energy in the form of radiations when it moves from higher energy level to lower energy level
D. it always gains energy in the form of light
11
119The dual nature of radiation was
proposed by :
A. De Broglie
B. Heisenberg
c. JJ Thomson
D. Einstein
11
120Infrared lamps are used in restaurants to keep the food warm. The infrared
radiation is strongly absorbed by water, raising its temperature and that of the food. If the wavelength of infrared
radiation is assumed to be ( 1500 n m )
then the number of photons per second of infrared radiation produced by an infrared lamp, that consumes energy at
the rate of ( 100 W ) and is ( 12 % ) efficient
only, is ( left(x times 10^{19}right) . ) The value of ( x ) is:
( left[text { Given: } boldsymbol{h}=mathbf{6 . 6 2 5} times mathbf{1 0}^{-mathbf{3 4}} boldsymbol{J}-boldsymbol{s}right] )
11
12120. If elements with principal quantum number n > 4
not allowed in nature, the number of possible elem
de elements
would have been
(a) 32
(b) 60
(c) 64
(d) 4
11
122Which of the following configuration
represents a noble gas?
( mathbf{A} cdot 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{10} 4 s^{2} 4 p^{6} 4 d^{10} 5 s^{2} )
B ( cdot 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{10} 4 s^{2} 4 f^{14} 5 s^{2} )
( mathbf{c} cdot 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{10} 4 s^{2} 4 p^{6} 4 d^{10} 5 s^{2} 5 p^{6} )
D ( cdot 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{10} 4 s^{2} 4 p^{6} 4 d^{10} 5 s^{2} 5 p^{3} )
11
123A neutral atom of certain elements has
15 electrons. How many unpaired electrons does it have?
( A )
B. 3
( c cdot 5 )
D.
11
124A cricket ball of ( 0.5 mathrm{kg} ) is moving with a
velocity of ( 100 mathrm{ms}^{-1} ). The wavelength
associated with its motion is:
A. ( 1 / 100 mathrm{cm} )
B. ( 66 times 10^{-34} ) m
D. 6.6 ( times 10^{-28} mathrm{m} )
11
125If the given four electronic configurations
(i) ( n=4, l=1 )
(ii) ( n=4,1=0 )
(iii) ( n=3,1=2 )
( (i v) n=3,1=1 )
are arranged in order of increasing energy, then the order will be:
A. (iv) < (ii) < (iii) < (i)
B. (ii) < (iv) < (i) < (iii)
c. (i) < (iii) < (ii) < (iv)
D. (iii) < (i) < (iv) < (ii)
11
126For a hypothetical ( boldsymbol{H} ) -like atom, the
wavelength in ( A^{o} ) for the spectral lines
for radiations from ( n=p ) to ( n=1 ) are
given by ( lambda=frac{1500 p^{2}}{p^{2}-1} ; ) where ( p= )
( 2,3,4 dots )
The wavelengths of most energetic photon and least energetic photons (in
( left.A^{o}right) ) during the transition are:
( mathbf{A} cdot 1500,2000 A^{circ} )
B . ( 2000,1500 A^{circ} )
( mathbf{c} cdot 1000,2000 A^{circ} )
D. ( 2000,1000 A^{circ} )
11
127Electron density studies have revealed that ( X ) and ( Y ) have an equal number of
electrons.What are ( X ) and ( Y ? )
( mathbf{A} cdot C a^{+} ) and ( mathbf{K} )
B. ( H^{+} ) and ( mathrm{He} )
c. ( mathrm{cl} ) and ( mathrm{F} )
D. ( O^{-} ) and ( S^{+} )
E. None of the above
11
128Every matter can be seen.
A. True
B. False
11
129The atomic number ( (z) ) of an element is
25. In its ground state, how many electrons are present in the N shell:
A . 13
B. 2
c. 15
D. 3
11
130Q. 1 Which of the following conclusions could not be derived from Rutherford’s
a-particle scattering experiment?
(a) Most of the space in the atom is empty
(b) The radius of the atom is about 10-10 m while that of nucleus is 10-15 m
(c) Electrons move in a circular path of fixed energy called orbits
(d) Electrons and the nucleus are held together by electrostatic forces of attraction
11
131Atomic number of an atom is equal to
the
A. number of protons
B. number of electrons
( c . ) both a and ( b )
D. sum of proton and electron
11
132The triad of nuclei that is isotonic is :
A ( cdot frac{14}{6} C, frac{15}{7} N, frac{17}{9} F )
В ( cdot frac{12}{6} C, frac{74}{7} N, frac{19}{9} F )
C ( cdot frac{14}{6} C, frac{14}{7} N, frac{17}{9} F )
D cdot ( _{6}^{14} C, frac{14}{7} N, frac{19}{9} F )
11
133Assertion
( alpha- ) rays have greater ionizing power
than ( beta- ) rays.
Reason
( alpha- ) particles carry two unit positive
charge while ( beta- ) particles carry only one unit negative charge.
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
11
134Which of the following transition will emit maximum energy in hydrogen atom?
A. ( 4 f rightarrow 2 s )
В. ( 4 d rightarrow 2 p )
( mathrm{c} .4 p rightarrow 2 s )
D. All have same energy
11
135Plots for ( 2 s ) orbital are:
( X, Y ) and ( Z ) are respectively
( mathbf{A} cdot R, R^{2} ) and ( 4 pi r^{2} R^{2} )
B ( cdot R^{2}, R ) and ( 4 pi r^{2} R^{2} )
( mathbf{C} cdot 4 pi r^{2} R^{2}, R^{2} ) and ( R )
D ( cdot R^{2}, 4 pi r^{2} R^{2} ) and ( R )
11
136An element ( A ) has electronic
configuration ( 2,8,13,2 . ) The number of electrons in the element having ( l=0 )
is:
A . 6
B. 8
( c .5 )
D. 4
11
137The energy of an electron in the first
Bohr orbit of H-atom is -13.6 eV. The
possible energy value(s) of the excited state(s) for electrons in Bohr orbits of
hydrogen is:
A. ( -3.4 e V )
в. ( -4.2 e V )
c. ( -6.8 e V )
D. ( +6.8 e V )
11
138Which of the following is Heisenberg uncertainty principle?
A ( cdot Delta x cdot Delta p geq frac{h}{4 pi} )
в. ( Delta x . Delta p=frac{h}{4 pi} )
c. ( Delta x . Delta p leq frac{h}{4 pi} )
D. ( Delta x . Delta p<frac{h}{4 pi} )
11
139is an obsolete
scientific model of the atom proposed by J. J. Thomson in 1904.
A. Musk melon model
B. Plum pudding model
c. Christmas melon model
D. Pudding model
11
140Indicate the incorrect statement:
A. Number of hybrid orbitals formed is equal to no. of atomic involved
B. ( 2 p_{x} ) and ( 2 p_{y} ) – orbitals of carbon can be hybridized to yield two new more stable orbitals
C. Effective hybridisation is not possible with orbitals of widely different energies
D. The concept of hybridisation has a greater significance in the VB theory of localised orbitals than ( M O ) theory.
11
141Among the following gaseous elements with atomic numbers, which will have
grater rate of diffusion?
( A cdot Z=7 )
B . ( Z=8 )
c. ( Z=10 )
D. ( Z=17 )
11
142If a radioactive element ( _{79} A u ) emits ( beta )
particle, what is the new group? ( _{79} A u ) belongs to group I B (copper family)?
( A cdot mid A )
B. IB
( c cdot | A )
D. II B
11
143Isotopes have similar:
A. physical properties
B. chemical properties
c. mass numbers
D. number of neutrons
11
144The correct order of energy difference
between adjacent energy levels in ( H )
atom:
( mathbf{A} cdot E_{2}-E_{1}>E_{3}-E_{2}>E_{4}-E_{3} )
B ( cdot E_{2}-E_{1}>E_{4}-E_{3}>E_{3}-E_{2} )
( mathbf{c} cdot E_{4}-E_{3}>E_{3}-E_{2}>E_{2}-E_{1} )
D ( cdot E_{3}-E_{2}>E_{4}-E_{3}>E_{2}-E_{1} )
11
145Isotopes are the atoms of
element having the atomic
number but ( _{-}-ldots-_{-} ) mass number
11
146The difference in number of angular nodes and the number of radial nodes in
the orbital to which the last electron of
chromium present is
11
147The oil drop experiment by R.A. Millikan was performed to find
A. charge on the neutron
B. charge on the electron
c. charge on the Proton
D. None of these
11
148The triad of the nuclei that is isotonic
is:
( mathbf{A} cdot_{6} N^{14}, 7 N^{14},_{9} F^{19} )
B cdot ( _{6} C^{14}, 7 N^{15},_{9} F^{17} )
( mathbf{c} cdot_{6} C^{14}_{7} N^{14},_{9} F^{17} )
( mathrm{D} cdot_{6} C^{12},_{7} N^{14},_{9} F^{19} )
11
149Three isotopes of an element have mass
numbers, ( M,(M+1) ) and ( (M+2) . ) If
the mean mass number is ( (M+0.5) )
then which of the following ratios may
be accepted for ( M,(M+1),(M+2) )
in that order?
A. 1: 1: 1
B. 4: 1: 1
( mathrm{c} .3: 2: 1 )
D. 2: 1: 1
11
150An electron and a photon each have a
wavelength of ( 1.00 mathrm{nm} . ) Find
(a) their momenta,
(b) the energy of the photon, and
(c) the kinetic energy of electron.
11
151Among the following orbitals which orbital will experience the larger
effective nuclear charge? ( 2 s, 3 s, 4 d, 4 f, 3 d, 3 p )
11
152An element has average atomic mass ( 20.426 u ) it has 2 isotopes with masses
( mathbf{2 2 . 1 8 2 4} ) and ( mathbf{1 9 . 9 5 7 4 .} ) Calculate the
abundance of its isotopes ( X-22 ) and
( X-20 )
11
153Which of the following path is assumed for the electron in the theory of
Rutherford?
A. Elliptical
B. Circular
c. spiral
D. All of the above
11
154Match the names of the scientists given
in column – I with contributions towards
the understanding of the atomic structure as given in column-II and choose the correct option from the
codes given below:
11
155Statement 1: Isotopes of a particular element have nearly identical chemical behavior.
Statement 2: They have identical electron configurations.
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
11
156What transition in the hydrogen spectrum have the same wavelength as Balmer transition ( n=4 ) to ( n=2 ) of
( H e^{+} ) spectrum?
11
157Which of the following are the limitations of Bohr’s model?
(i) It could not explain the intensities or
the fine spectrum of the spectral lines.
(ii) No justification was given for the
principle of quantisation of angular
momentum.
(iii) It could not explain why atoms should combine to form bond.
(iv)It could not successfully applied to single electron atoms.
( A cdot(i),(i i),(i v) )
B . (ii), (iii)
c. (i), (iii), (iv)
D. (i),(ii),(iii)
11
158Bohr’s model can
explain
This question has multiple correct options
A. The spectrum of hydrogen atom only.
B. Spectrum of an atom or ion containing single electron only.
C. The stability of atom.
D. The solar spectrum.
11
159Explain the important features of Rutherford’s Planetary model and write
its defects
11
16014. The energy required to excite an electron from the ground
state of hydrogen atom to the first excited state, is
(a) 1.602 x 10-14J (b) 1.69 x 10-16J
(c) 1.632 x 10-18 J. (d) 1.656 x 10-20 J
11
161An electron in the hydrogen atom is
excited from the first orbit to the fifth
orbit. Find the change in energy of the electron in eV.
A ( .+(13.6 times 24) / 25 )
в. ( -(13.6 times 4) / 5 )
C . ( -(0.529 times 4) / 5 )
D. ( -(13.6 times 4) / 9 )
11
16250. If the minimum wavelength obtained in an X-ray
2.5 x 10 m, the operating potential of the tube will
(a) 2 kV
(b) 3 kV
(c) 4 kV
(d) 5 kV
11
163a) An ion with mass number 37
possesses one unit of negative charge.
If the ion contains ( 11.1 % ) more neutrons
than the electrons. Find the symbol of the ion.
b) An electron is in 3d orbitals. Give the
possible values of ( n, ) land ( m_{1} )
c) What is the maximum number of
emission lines, When the excited
electron of a ( boldsymbol{H} ) atom in ( boldsymbol{n}=boldsymbol{6} ) drops to the ground state?
11
164What is the mass of a lead atom?11
165The two p orbitals are deflected by an angle of:
A ( cdot 45^{circ} )
B . ( 180^{circ} )
( c .90^{circ} )
D. ( 120^{circ} )
11
166Q. 13 Chlorine exists in two isotopic forms. CL-37 and Cl-35 but its atomien
mass is 35.5. This indicates the ratio of Cl-37 and Cl-35 is approximately
(a) 1:2
(b) 1 : 1
(c) 1:3
(d) 3:1
Are
The free
ar
11
167Order of number of revolution/sec
( gamma_{1}, gamma_{2}, gamma_{3} ) and ( gamma_{4} ) for ( I, ) II, III and IV orbits
is:
A ( cdot gamma_{1}>gamma_{2}>gamma_{3}>gamma_{4} )
В ( cdot gamma_{4}>gamma_{3}>gamma_{2}>gamma_{1} )
C ( cdot gamma_{1}>gamma_{2}>gamma_{4}>gamma_{3} )
D. ( gamma_{2}>gamma_{3}>gamma_{4}>gamma_{1} )
11
168Q41. Symbols 36Br and 79Br can be written, whereas symbols 35Br and 35Br are not acceptable.
Burritton as subscrint while
11
169In an atom two electrons move around
the nucleus in circular orbitals of radii
( R ) and ( 4 R ). The ratio of the time taken by
them to complete one resolution is:
A . 1: 4
B. 4: 1
( c cdot 1: 8 )
D. 8: 7
11
170The correct size for quanta for different contributions of energy for gaseous molecules is :
A. electronic > vibrational > rotational > tranlational
B. electronic < vibrational < rotational electronic >rotational > tranlational
D. rotational > vibrational > translational > electronic
11
171On the basis of Rutherford’s model of an
atom, which sub-atomic particle is
present in the nucleus of an atom?
A. Protons
B. Electrons
c. Neutrons
D. All of the above
11
172Which of the following statement is not
correct?
A. Atomic no.of A,B,C are 40,57,105 respectively
3. Group no of ( A, B, C ) are IV ( B ), III ( B ) and ( V B ) respectively
c. Period no of ( A, B, C ) are 4 th ( , 5 ) th and 6 th respectively
D. ( mathrm{C} ) is a radioactive element
11
173Explain with examples:
(i) Atomic number
(ii) Mass
number,
(iii) Isotopes and
(iv) Isobars.
Give any two uses of isotopes.
11
174Which of the following is/are example(s) of induced radioactivity
reaction?
Select correct statement(s)
A. Photon or particle is ionised and collected by the positive electrode in a Geiger counter
B. A scintillation counter contains a phosphor, a substance that emits a flash of light when struck by a photon or particle.
c. Both of the above
D. None of the aobve
11
175If first ionisation energy of hydrogen is
( boldsymbol{E}, ) then the ionisation energy of ( boldsymbol{H} boldsymbol{e}^{+} ) would be:
A. ( E )
в. ( 2 E )
( c .0 .5 E )
D. ( 4 E )
11
176According to Schrodinger model, nature of electron in an atom is as:
A. particles only
B. wave only
c. both simultaneously
D. sometimes wave and sometimes particle
11
177The periods of the periodic table are numbered according to ……………….ofthe valence shell.
A. azimuthal quantum number
B. principal quantum number
C. magnetic quantum number
D. spin quantum number
11
178Which two orbitals are located along the
axis, and not between the axis?
( mathbf{A} cdot d_{x^{2}-y^{2}}, d_{z^{2}} )
B . ( d_{x y}, p_{z} )
( mathbf{c} cdot d_{y z}, p_{x} )
D. ( d_{y z}, d_{x^{2}-y^{2}} )
11
179Bohr’s theory is applicable to
This question has multiple correct options
( mathbf{A} cdot H e^{+} ) ion
B. ( L i^{2+} ) ion
C . Tritium ( _{1} H^{3} )
( mathbf{D} cdot_{1} H^{1} )
11
180The wave number for the shortest
wavelength transition in the Balmer series of atomic hydrogen is :
A . ( 8225714 mathrm{m}^{-1} )
В. ( 1523693 m^{-1} )
( mathbf{c} cdot 5333 c m^{-1} )
D. ( 27419 mathrm{cm}^{-1} )
11
181Answer the following questions for Zn
atom:

How many electrons have ( l-m=1 ? )

11
182The line spectrum is noticed during the transition of an electron from higher
excited state to lower one in ( boldsymbol{H} ) -atom
only when an electron falls from:
A . ( 2 s ) -orbital to ( 1 s ) -orbital
B. 2p-orbital to 1s-orbital
c. ( 3 s ) -orbital to ( 2 p ) -orbital
D. ( 4 p ) -orbital to ( 2 p ) -orbital
11
183A tube of light emits light of wavelength ( mathbf{5 2 9 6} ) A. The bulb is rated as 200watt
and ( 20 % ) of the energy is converted into light. If the whole light emitted is allowed to fall on a metal surface
having work function ( 3.00 times 10^{-19} J )
calculate the no. of electrons ejected in
( mathbf{1 0} boldsymbol{s} )
11
184Boron occurs in nature in the form of
two isotopes having atomic mass 10 and ( 11 . ) Calculate the percentage abundances of two isotopes respectively in a sample having atomic mass 10.80
A . 10,90
B. 30, 70
c. 20,80
D. 25,75
11
185Which of the following disapproved Thomson’s model?
A. The nuclear model of an atom
B. The electron model of an atom
c. The atomic model of an atom
D. None of above
11
186If in the ground state an atom has seven valence electrons, which of the following is the correct electronic configuration of the atom in the ground state?
A ( .3 s^{1} 3 p^{6} )
В. ( 3 s^{6} 3 p^{text {। }} )
c. ( 3 s^{1} 3 p^{4} 3 d^{2} )
D. ( 3 s^{3} 3 p^{4} 3 d^{1} )
E ( .3 s^{2} 3 p^{5} )
11
187Which of the following is/are derived by Hisenberg in his uncertainty principle?
A ( cdot Delta p times Delta x=frac{h}{4 pi} )
B . ( triangle v times triangle x=frac{h}{4 pi m} )
C ( cdot triangle E times Delta t=frac{h}{4 pi} )
D. ( Delta p times Delta E=frac{h}{4 pi} )
11
188What happens when both of the orbitals in a molecule are in phase, either both
positive or both negative and the electrons in the bonds are at their
lowest energy level?
A. Bonding takes place.
B. The chemicals don’t react.
c. The atoms don’t bond
D. Bonding doesn’t take place.
E. The electrons in the atoms don’t share orbitals
11
189In a certain electronic transition in the
hydrogen atoms from an initial state (1) to a final state (2), the difference in the
orbital radius ( left(r_{1}-r_{2}right) ) is 24 times the
Identify the transition.
( A cdot 5 rightarrow 1 )
B. 25 ( rightarrow 1 )
( c cdot 8 rightarrow 3 )
( D cdot 6 rightarrow 5 )
11
190ANCI
1. If 13.6 eV energy is required to ionise a hydrogen atom,
then the required energy to remove an electron from
n=2 is
(a) 10.2 eV
(b) O eV
(c) 3.4 eV
(d) 6.8 eV (AIEEE 2002)
11
191What is the energy in ( e V ) required to
excite the electron from ( n=1 ) to ( n=2 )
state in hydrogen atom? ( (n= ) principal
quantum number)
A . 13.6
в. 3.4
c. 17
D. 10.2
11
192The proton is heavier than an electron by
A. 1835 times
B. 18000 times
c. 1000 times
D. 100 times
11
193An orbital with ( l=0 ) is Symmetrical
A. ( x- ) axisonly
B. ( y- ) axisonly
c. ( z- ) axisonly
D. nucleus
11
194By charging the metal electrodes and gas inside the cathode ray tube:
A. the electron particle were produced
B. the proton particle were produced
c. the neutron particle were produced
D. none of the above
11
195Which of the following force balance the electrostatic force of attraction between
the positively and negatively charged particles in Rutherford model?
A. The negatively charge particles repulsion.
B. The high velocity of the electrons moving in circular path
c. The linear movement of the nucleus
D. None of these
11
196What will be the energy of one photon of radiation whose frequency is ( 5 times ) ( 10^{14} H z ? )
A. ( 199.51 J )
в. ( 3.3 times 10^{-19} mathrm{J} )
c. ( 6.626 times 10^{-34} J )
D. ( 2.31 times 10^{5} J )
11
197Moseley’s equation is represented as
( sqrt{boldsymbol{v}}=boldsymbol{a}(boldsymbol{Z}-boldsymbol{b}) ) where a and b are
constants If ( boldsymbol{O} boldsymbol{A}=mathbf{1}, ) then atomic
number of the elements showing
frequency of ( 400 H z ) is?
A . 2
( B )
( c .40 )
0.19
11
198Assertion
Isotopes of an element have same
chemical properties
Reason
Chemical properties do not depend on
the number of neutrons
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
11
199State True or False.
( H^{2} ) is more reactive than ( H^{1} )
A. True
B. False
11
200According to Bohr theory, the angular momentum of electron in 5 th orbit is:
A ( cdot_{25} frac{h}{pi} )
в. ( _{1} frac{h}{pi} )
( mathrm{c} cdot_{10} frac{h}{pi} )
D. ( _{2.5} frac{h}{pi} )
11
201If the threshold energy for ejection of electron from metal is 1.4 eV and light of 3eV falls on the metal, then the kinetic
energy of photoelectron emitted will be:
A ( .2 .6 times 10^{-19} mathrm{J} )
В. ( 1.6 times 10^{-18} mathrm{J} )
c. ( 2.2 times 10^{-19} mathrm{J} )
D. ( 3.2 times 10^{-20} mathrm{J} )
11
202What are the limitations of Rutherford’s
nuclear model?
A. Electrons should undergoes spiral path and fall into nucleus
B. Could not explain hydrogen spectrumm
c. Electron lose energy while in motion
D. All of these
11
203The two particle ( A ) and ( B ) have de Broglie wavelengths 1 nm and 5 nm respectively. If mass of ( A ) is 4 times that of mass of ( B )
the ratio of KE of ( A ) and ( B ) would be:
A . 5:
B. 25: 4
( c cdot 20: 1 )
D. 5: 4
11
204The orbital diagram which violates the aufbau principle’ is:
( A )
( 2 s ) ( boldsymbol{2 p} ) ( uparrow downarrow ) ( uparrow downarrow quad uparrow )
в. ( 2 s ) 一 2 ( uparrow ) ( uparrow downarrow quad uparrow quad uparrow )
( c )
( 2 s ) ( 2 p ) ( uparrow downarrow ) ( uparrow quad uparrow quad uparrow )
D. ( 2 s )
( prec 2 p ) Why ( uparrow downarrow ) ( uparrow downarrow|uparrow downarrow| uparrow )
11
205If the above radial probability curve
indicates ‘2s’ orbital, the distance
between the peak points ( boldsymbol{X}, boldsymbol{Y} ) is:
A ( .2 .07 hat{k} )
в. 1.59 .
( .0 .53 AA )
( .2 .12 hat{k} )
11
206What is meant by the statement that
“the atomic number of sodium is
eleven”?
11
207A hydrogen like species (atomic number ( Z ) ) is present in a higher excited
state of quantum number ( n ). This excited atom can make a transition to
the first excited state by successive emission of two photons of energies ( 10.20 e V ) and ( 17.0 e V ) respectively. Alternatively, the atom from the same excited state can make a transition to
the second excited state by successive emission of two photons of energy ( 4.25 e V ) and ( 5.95 e V ) respectively.
Determine the value of ( Z ).
A . 1
B. 2
( c cdot 3 )
D. 4
11
208Which of the following statements is
false?
A. Photon has momentum as well as wavelength
B. Frequency of emitted radiation from a lower wavelength to higher wavelength as the temperature increases
C. Rydberg constant has unit of energy
D. Splitting of spectral lines an electrical field is called Stark effect
11
209Angular momentum of an electron is quantized according to:
A. Planck
B. Rutherford
c. Bohr
D. Thomson
11
21018. A photon of wavelength 4400 X is passing through
vacuum. The effective mass and momentum of the photon
are respectively
(a) 5 x 10-36 kg, 1.5 x 10-27 kg-m/s
(b) 5 x 10-35 kg, 1.5 x 10-26 kg-m/s
(c) Zero, 1.5 x 10-26 kg-m/s
(d) 5 x 10-36 kg, 1.67 x 10-48 kg-m/s
11
211The quantum theory is a suggestion that heat, light, electricity or any other form of energy.
A. Cab be if any size
B. Exist in discrete bundles
c. Is continuous
D. Is transfered in as small amount as one could imagine
11
212An electron make transition from orbit
number ( N ) to ( P^{t h} ) orbit in ( H- ) atom and
emit the photon of wavelength ( (lambda) . ) In
orbit ( boldsymbol{P}, ) velocity of electron in ( boldsymbol{H}- ) atom is maximum. Which of the following wavelength ( (lambda) ) is not possible?
(Where ( 1 / R=912 A) )
( mathbf{A} cdot 1216 stackrel{circ}{A} )
B . 972.8 A
( c cdot 1026^{circ} )
D. 3973 h
11
213Maximum number number of electron
that may be present on a ( 4 f ) -orbital is:
( A cdot 2 )
B. 4
c. 7
D. 14
11
214Rutherford said that electrons revolve
around the nucleus in circular paths called:
A . circles
B. orbits
c. wheels
D. sphere
11
215Atoms may be regarded as comprising of protons, neutrons and electrons. If the
mass attributed to a neutron were
halved and that attributed to the
electron were doubled, the atomic mass
of ( frac{12}{6} mathrm{C} ) would:
A. remain approximately the same
B. be approximately doubled
c. be approximately halved
D. be reduced approximately by 25%
11
216. 40 The effect of uncertainty principle is significant only for motion of
microscopic particles and is negligible for the macroscopic particles.
Justify the statement with the help of a suitable example.
11
217The momentum of electron is:
A. directly proportional to wavelength
B. inversly proportional to wave number
C. inversly proportional to wavelength
D. cannot be determined
11
218In ground state of chromium atom ( (Z=24) ) the total number of orbitals
populated by one or more electrons is??
A . 15
B . 16
c. 20
D. 14
11
219What is the new quantum number proposed by Sommerfeld?
A. Principal
B. spin
c. Azimuthal
D. Magnetic
11
2202. In the hydrogen atom, when electron jumps from second
to first orbit, then energy emitted is
(a) -13.6 eV
(b) -27.2 eV
(c) -6.8 eV
(d) None of these
(AIEEE 2002)
11
221Number of nodal planes in ( 4 p ) suborbit
will be:
A .
B.
( c cdot 2 )
D.
11
222The e/m ratio is maximum for:
A . ( D^{+} )
в. ( H e^{+} )
( mathrm{c} cdot H^{+} )
D. ( H e^{2+} )
11
223A single electron orbit around a stationary nucleus of charge +Ze where ( mathrm{Z} ) is the atomic number and ‘e’ is the
magnitude of the electric charge. The hydrogen-like species required ( 47.2 e v ) to excite the electron from the second
Bohr orbit to the third Bohr orbit. The
value of ( Z ) is:
A. 5
B. 3
( c cdot 2 )
( D )
11
224Angle between p orbitals is:
A ( cdot 90^{circ} )
B . ( 180^{circ} )
( c cdot 120^{circ} )
D. ( 109^{circ} 28 )
11
225Which of the following properties of atom could be explained correctly by Thomson model of atom?
A. Overall neutrality of atom.
B. Spectra of hydrogen atom.
c. Position of electrons, photons and neutrons in atom.
D. Stability of atom.
11
226A small amount of solution containing ( ^{24} mathrm{Na} ) radio nuclide with activity ( boldsymbol{A}= ) ( 2 times 10^{3} ) dps was administered into
blood of a patient in hospital. After 5 hour, a sample of the blood drawn out from the patient showed an activity of 16 dpm per cc. ( t_{1 / 2} ) for ( ^{24} mathrm{Na}=15 ) hr. The
activity of blood sample drawn after a further time of 5 hr is :
A. 0.2118 dpm per ( m L )
B. 0.4232 dps per ( m L )
c. 0.4232 dpm per ( m L )
D. 0.2118 dps per ( m L )
11
227Which of the following sets of quantum numbers is correct for an electron in ( 3 d )
orbital?
A ( cdot n=3, l=2, m=-3, s=+frac{1}{2} )
в. ( n=3, l=3, m=+3, s=-frac{1}{2} )
c. ( n=3, l=2, m=-2, s=+frac{1}{2} )
D. ( n=3, l=2, m=-3, s=-frac{1}{2} )
11
228Q. 22 Arranges, p and d subshells of a shell in the increasing order of effective
nuclear charge (Zeff) experienced by the electron present in them.
11
229The sum of all the quantum numbers of helium atom is :11
230Statement 1: Gas-phase elements
absorb or emit only specific wavelengths of visible light when
excited by an electric current.
Statement 2: The energy levels that
electrons can occupy in gas-phase
atoms and molecules are continuous.
A. Both Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation of Statement 1
B. Both Statement 1 and Statement 2 are correct and 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.
E. Both the Statement 1 and Statement 2 are not correct.
11
2319. Select the correct statement(s).
(a) Electromagnetic radiation is a form of energy
consisting of oscillating electric and magnetic fields.
(b) Visible light is a form of electromagnetic radiation
(c) The electromagnetic spectrum of sunlight received at
the Earth’s surface differs from that emitted by the Sun
(d) Ultraviolet radiation is absorbed in the stratosphere
by ozone and oxygen
11
232The active mass of ( 7.0 mathrm{g} ) of nitrogen in a
( 2.0 L ) container would be:
A . 0.25
B. 0.125
( c .0 .5 )
D. 14.0
11
2336. Which of the following transitions in hydrogen atoms
emits photons of the highest frequency?
(a) n = 6 to n = 2 (b) n= 2 to n=1
(c) n=1 to n = 2 (d) n= 2 to n= 6
(AIEEE 2007)
11
234The spectrum of a molecule is so detailed that a molecule can be
identified by its spectrum.
A. Only if it is small
B. Only by test-tube analysis
c. with great difficulty
D. Easily, like a fingerprint
11
2357. The maximum angular speed of the electron of a hydrogen
atom in a stationary orbit is
(a) 6.2 x 10′) rad s (b) 4.1 x 101 rad s
(c) 24 x 100 rad s-1 (d) 9.2 x 10° rad s-
11
236The mass number of an atom is slightly less than the actual atomic mass. Give
reasons.
11
237Which of the statements are the
drawbacks of Rutherford’s model of an
atom?
A. The orbital revolution of the electron is not expected to be stable
B. Any particle in a circular orbit would undergo a acceleration and the charged particles would radiate energy
c. The revolving electron would lose energy and finally fall into the nucleus
D. All of the above
11
238Thomson proposed the model of an
atom similar to :
A. christmas tree
B. christmas pudding
c. chocolate
D. none of the above
11
239Q29. Using sp and d notations, describe the orbitals with following quantum numbers :
(a) n = 1, 1 = 0, (b) n = 4,1 = 3. (c) n = 3,1 = 1, (d) n = 4, 1 = 2
1111111111
11
240( boldsymbol{alpha}- ) rays are composed of:
A. fast moving protons
B. fast moving electrons
C. the same particles that constitute positive rays
D. particles with four mass units and two positive charges
11
241K shell of ( _{7}^{14} N ) has 2 electrons. How
many electrons are present in the
shell ?
11
242Which of the following statements is
incorrect?
A. Number of electron for ( n+l=5 ) in ( C o^{+3} ) ion is six
B. In electronic configuration of Mn, electrons having value of ( m+l=0 ) are 13
C. Three radial nodes are present in the spherically symmetrical orbital of the fourth main shell
D. None of the above
11
243Find the minimum uncertainty in the
position of proton when ( u_{p r o t o n}=0.01 times ) speed of light.
A ( cdot 3.15 times 10^{3} m )
В. ( 13.2 times 10^{-14} mathrm{m} )
c. ( 6.6 times 10^{-14} m )
D. ( 1.05 times 10^{-14} m )
11
244The shortest and longest wave number in ( mathrm{H} ) spectrum of Lyman series is ( (mathrm{R}= ) Rydberg constant):
A ( cdot frac{3}{4} ) R, R
в. ( frac{1}{R}, frac{4}{3}, ) R
c. ( _{R, frac{4}{3} R} )
D. ( _{R,} frac{3}{4} R )
11
245ng
1.
0
10
3. Imagine an atom made up of a proton and a hypothetical
particle of double the mass of the electron but having the
same charge as the electron. Apply the Boh’r atom model
and consider all possible transitions of this hypothetical
particle to the first excited level. The longest wavelength
photon that will be emitted has wavelength 2 (given in terms
of the Rydberg constant R for the hydrogen atom) equal to
(a) 9/(5R)
(b) 36/(5R)
(c) 18/(5R)
(d) 4/R
11
246A potential difference of ( 20 K V ) is applied across an ( X-r a y ) tube. Find
the minimum wavelength of ( boldsymbol{X}-boldsymbol{r} boldsymbol{a} boldsymbol{y} )
generated
11
2478. The transition from the state n = 4 to n = 3 in a hydrogen
will be obtained in the transition from
(a) 21
(b) 3 →
(c) 4 → 2
(d) 5 4 (AIEEE 2009)
11
248What is the de Broglie wavelength of
(a) a bullet of mass ( 0.040 mathrm{kg} ) travelling at the speed of ( 1.0 mathrm{km} / mathrm{s} )
(b) a ball of mass ( 0.060 mathrm{kg} ) moving at a speed of ( 1.0 mathrm{m} / mathrm{s}, ) and
(c) a dust particle of mass ( 1.0 times 10^{9} k g )
drifting with a speed of ( 2.2 mathrm{m} / mathrm{s} ? )
11
249Which among the following transitions will give Lyman series in Hydrogen emission atomic spectra?
( A cdot K ) to ( L )
B. L to M, N etc
c. к to L, M, N etc
D. L, M, N etc to K
11
250Write the range of frequencies of electromagnetic waves which propagate through sky wave mode.11
251Copper has 29 electrons and 35
neutrons. Find the atomic mass.
A . 62
B. 63
( c cdot 54 )
( D cdot 64 )
11
252All atoms contain neutrons in their
nuclei except:
A. Protium
B. Helium
c. Neon
D. Chlorine
11
253Isotopes of an element have:
This question has multiple correct options
A. the same physical properties.
B. same chemical properties.
C. different number of neutrons.
D. different atomic numbers.
11
254Two atoms are said to be isobars if ?
A. They have same atomic number but different mass number
B. They have same number of electrons but different number of neutrons
C. They have same number of neutrons but different number of electrons
D. Sum of the number of protons and neutrons is same but the number of protons is different.
11
255Which of the following species has (have) five unpaired electrons?
This question has multiple correct options
A . cs
в. мп
( c cdot M n^{2+} )
D. ( mathrm{Fe}^{2} )
11
256In which pairs do both species have the same number of unpaired electrons in ( mathrm{p} )
orbitals?
10 and ( C l^{+} )
2. ( F^{+} ) and ( G a^{-} )
3. ( mathrm{N} ) and ( boldsymbol{K} boldsymbol{r}^{boldsymbol{3}+} )
A. 1,2 and 3 are correct
B. 1 and 2 only are correct
c. 2 and 3 only are correct
D. 1 only is correct
11
2579. Energy required for the electron excitation in Lit from
the first to the third Bohr orbit is
(a) 12.1 eV
(b) 36.3 eV
(c) 108.8 eV
(d) 122.4 eV (AIEEE 2011)
11
258Spot the mistakes in the given
statements and correct them.
(a) Lanthanides and actinides are
included in the main body of periodic
table.
(b) Titanium, chromium and
manganese are coinage elements.
11
259Write any two uses of isotopes.11
260A square planar complex is formed by hybridization of which atomic orbitals?
A ( cdot s, p_{x}, p_{y}, d_{y z} )
B. ( s, p_{x} . p_{y}, d_{x^{2}-y^{2}} )
C ( cdot s, p_{x} cdot p_{y}, d_{z} )
D. ( s, p_{x}, p_{y}, d_{x y} )
11
261Which one of the following is not the
characteristic of Planck’s quantum
A. The energy is not absorbed or emitted in whole number multiple of quantum
B. Radiation is associated with energy
C. Radiation energy is not emitted or absorbed continuously but in the form of small packets called quanta
D. This magnitude of energy associated with a quantum is proportional to the frequency
11
262An isotone of ( _{32}^{76} ) Ge is:
A ( cdot frac{77}{32} mathrm{Ge} )
B. 家
( A s )
( mathrm{c} cdot frac{77}{34} mathrm{Se} )
11
263Naturally occurring boron consists of two isotopes whose atomic weights are
10.01 and 11.01. The atomic weight of natural boron is 10.81 . Calculate the
percentage of each isotope in natural boron.
11
264True or False
According to JJ. Thomson mode
electrons revolve around the nucleus.
11
265What is the energy of electron in second
Bohr’s orbit of ( L i^{2+} ? )
11
266An isotone of ( _{32}^{76} ) Ge is:
This question has multiple correct options
( mathbf{A} cdot_{32}^{77} G e )
( mathbf{B} cdot_{33}^{77} A s )
( mathbf{c} cdot_{34}^{77} S e )
( mathbf{D} cdot_{34}^{78} S e )
11
267Write nuclear reaction equations for:
(i) ( alpha ) – decay of ( _{88}^{226} R a )
(ii) ( alpha )
decay of ( _{94}^{242} P uleft(text { iii) } beta^{-} text {- decay of }_{15}^{32} Pright. )
(iv) ( beta^{-} ) – decay of ( _{83}^{210} B i(v) beta^{+}- ) decay of ( _{6}^{11} C )
(vi) ( beta^{+} ) – decay
of ( _{43}^{97} T cleft(text { vii) Electron capture of } frac{120}{54} X eright. )
11
268The discovery of Balmer and Lyman series was made before
proposing model for structure of atom.
This question has multiple correct options
A. Thomson
B. Rutherford
c. Bohr
D. Planck
11
269If number of electrons in an atom is 8
and number of protons is also ( 8, ) then
( (i) )
what is the atomic number of the atom
? and
(II) what is the charge on the
atom?
11
270The orbital angular momentum of an electron is ( sqrt{3} frac{h}{pi}, ) Which of the following
of angular momentum of this electron revolving in unknown Bohr orbit?
A ( cdot frac{h}{2 pi} )
в. ( frac{h}{pi} )
( mathrm{c} cdot_{3} frac{h}{pi} )
D. none of the above
11
271Ratio of frequency of revolution of
electron in second excited state of ( boldsymbol{H} boldsymbol{e}^{+} )
and first excited state of ( boldsymbol{H} ) is ( frac{boldsymbol{2}^{x}}{mathbf{3}^{y}} . ) Then
the value of ( x+y ) is:
11
272In an orbital, the signs of lobes indicate
the:
A. sign of the wave function
B. sign of the probability distribution
c. presence or absence or electron
D. sign of charge
11
273How are isotopes of the same element
similar?
A. They have the same particles in the nucleus
B. They have the same number of neutrons
C. They are equally abundant in nature
D. They have the same number of protons
E. They have the same mass
11
274The MRI (magentic resonance imaging) body scanners used in hospitals operate with ( 400 mathrm{MHz} ) radio frequency energy. The wavelength corresponding to this radio frequency is:
A. ( 0.75 mathrm{m} )
B. 0.75 cm
c. ( 1.5 mathrm{m} )
D. ( 2 mathrm{cm} )
11
275Not considering the electron spin, the degeneracy of second excited state is 9 while the generality of the first excited
state of ( boldsymbol{H} ) atom is:
A.
B. 2
( c cdot 3 )
( D )
11
276Assertion
(A): Hydrogen has one electron in its orbit but it produces several spectral lines. Reason (R): There are many excited energy levels available.
A. Both A and R are rue and R is the correct explanation of A
B. Both A and R are true and R is not correct explanation of
C. A is correct and R is incorrect
D. A is incorrect and R is correct
11
277Q. 17 Identify the pairs which are not of isotopes?
(a) ZX, 188 (b) 35x, 327 (c) & X, AY
(d) 8X,Y
11
278Calculate the ratio of moles of ( 3.6 g ) of
water and ( 4.4 g ) of carbon dioxide.
Atomic mass of ( boldsymbol{C}=mathbf{1 2 u}, boldsymbol{H}= )
( mathbf{1} boldsymbol{u}, boldsymbol{O}=mathbf{1 6} boldsymbol{u} )
11
279An electron has ( u_{r m s} ) value at ( 27^{0} C )
( left(text { Given } boldsymbol{m}_{e}=mathbf{9 . 1 0 8} times mathbf{1 0}^{-mathbf{3 1}} mathbf{k g}right) )
This question has multiple correct options
A. ( 3.7 times 10^{4} m / ) sec
B . ( 1.3 times 10^{5} mathrm{km} / mathrm{hr} )
c. ( 1.3 times 10^{5} mathrm{m} / mathrm{sec} )
D. ( 11.7 times 10^{4} k m / h r )
11
280Uncertainty in position and momentum are equal. Uncertainty in velocity is:
A ( cdot sqrt{h / pi} )
B. ( sqrt{h / 2 pi} )
c. ( 1 / 2 m sqrt{h / pi} )
D. None of these
11
281Isobars are:
A. the atoms of same element having the same atomic number but different mass numbers
B. the atoms of same element having different atomic numbers but same mass number
C. atoms of different elements with same atomic
number which have different mass numbers
D. atoms of different elements with different atomic numbers which have same mass number
11
282Supposing the ionisation energy of hydrogen like species is 960 eV. Find out the value of principal quantum number having the energy equal to – 60
( mathrm{eV} )
( A cdot n=2 )
B. ( n=3 )
( c cdot n=4 )
( D cdot n=5 )
11
283The observation of discrete energy lines suggests that an electron in an atom can have only certain or definite energies.
A . True
B. False
11
284All of the following statements are true
about Bohr’s model of the atom except
which one of the following?
A. An electron may assume an infinite number of velocities
B. An atom is most stable when its electronic configuration is that of the ground state
C. The electron shell numbers represents the principal energy levels
D. Electrons in orbitals closest to the nucleus have the
lowest energy
E. They are all consistent
11
285Which statement below is not
acceptable with the concept
of isotopes?
A. Each elements is composed of atoms
B. All atoms of an element are identical
C. The atoms of different elements have different
chemical and physical properties
D. The combining of elements leads to the formation of compounds
E. In a compound, the kinds and numbers of atoms are constant
11
286Silver crystallises in fcc lattice. If edge length of the cell is ( 4.07 times 10^{-8} mathrm{cm} ) and
density is ( 10.5 g mathrm{cm}^{3} ), calculate the
atomic mass of silver.
11
287If number of electrons in an atom is 8
and number of protons is also 8 , then give the atomic number of atom and the
charge on the atom.
A. (i) Atomic number ( =8, ) (ii) Charge ( =0 )
B. (i) Atomic number ( =4, ) (ii) Charge ( =0 )
c. (i) Atomic number ( =8, ) (ii) Charge ( =+1 )
D. (i) Atomic number ( =4, ) (ii) Charge ( =+1 )
11
288Hydrogen atom, unipositive helium, dipositive lithium contain single
electron in the same shell. Is the radius
of the shell same in all cases? Give
reason.
11
289It was known by 1900 that the atom was not ( a_{dots} dots dots dots, dots ) particle but contained at least one sub-atomic particle the
electron identified by J.J. Thomson
A. simple, divisible
B. complex, indivisible
c. simple, indivisible
D. complex, divisible
11
290Which of the following is the electron
configuration of a transition metal?
A ( cdot 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{2} )
B ( cdot 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} )
C ( cdot 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{2} 3 d^{5} )
D ( cdot 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{2} 3 d^{10} 4 p^{2} )
11
291The blocks of the periodic table are named for the ( ldots ). orbital to be
occupied according to the building-up principle.
1. first
2. last
3. highest
4. lowest
11
29276. According to Bohr’s theory of hydrogen atom, the product
of the binding energy of the electron in the nth orbit and
its radius in the nth orbit
(a) is proportional to n?
(b) is inversely proportional to n’
(c) has a constant value of 10.2 eV-Å
(d) has a constant value of 7.2 eV-Å
11
293The energy of the second Bohr orbit of hydrogen atom is – 3.41 eV. The energy of
the second orbit of ( boldsymbol{H} boldsymbol{e}^{+} ) would be:
A . – ( 0.85 mathrm{ev} )
B . -13.6ev
c. -1.70ev
D. – ( 6.82 mathrm{eV} )
11
294The value of ‘ ( m_{s} ) ‘ for an electron
spinning in clock-wise direction is and for anti-clockwise
direction is
11
295The ratio of ( e / m ) for a cathode ray:
A. varies with a gas in a discharge tube
B. is fixed
C. varies with different electrodes
D. is maximum if hydrogen is taken
11
296Assertion : ( beta- ) particles are deflected
more than ( alpha- ) particles in a given
electric field.

Reason: Charge on ( alpha- ) particles is
larger than on ( beta- ) particles.
A. If both (A) and (R) are correct, and (R) is the correct explanation of (A).
B. If both (A) and (R) are correct, but (R) is not the correct explanation of (A)
c. If (A) is correct, but (R) is incorrect.
D. If (A) is incorrect, but (R) is correct
E. If both (A) and (R) are incorrect

11
297A certain particle carries ( 2.5 times 10^{-16} C )
of static electric charge. Calculate the
number of electrons present in it.
11
298Which electronic level would allow the
hydrogen atom to absorbs a photon but not to emit a photon?
A . ( 3 s )
B . ( 2 s )
c. ( 1 s )
D. ( 4 s )
11
299If a sub-shell is denoted as ( 2 p ) then its magnetic quantum number values are
A . – 3, -2, – –
B. – -1, 0, + 1
( c .-2,-1,0 )
D. 0, 1, 2
11
300Sub atomic particles of atoms are:
A. protons
B. electrons
c. neutrons
D. all of these
11
301The position of both, an electron and a range of helium atom is known within
1.0 ( n m . ) Further the momentum of the
electron is known within a range of ( mathbf{5 . 0} times mathbf{1 0}^{-mathbf{2 6}} mathbf{k g} mathbf{m s}^{-1} . ) The minimum
uncertainty in the measurement of the
momentum of the helium atom is:
A. ( 50 mathrm{kg} mathrm{ms}^{-1} )
B. ( 80 mathrm{kg} mathrm{ms}^{-1} )
c. ( 80 times 10^{-26} ) kg ( m s^{-1} )
D. ( 5 times 10^{-26} mathrm{kg} mathrm{ms}^{-1} )
11
302Shape of P-Orbital is:
A. spherical
B. dumb-Bell
c. double dumb bell
D. none of these
11
303The ionization energy of hydrogen atom
is ( 13.6 mathrm{eV} ). The energy required to excite the electron in a hydrogen atom from the ground state to the first excited state is:
A ( cdot 1.69 times 10^{-18} mathrm{J} )
В. ( 1.69 times 10^{-23} ) 」
c. ( 1.69 times 10^{23} ) 」
D. ( 1.69 times 10^{25} mathrm{J} )
11
304Assertion
Only one in 20000 of alpha particles deflected in Rutherford’s experiment.
Reason

Most of the space in the atom is empty.
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

11
305Cobalt-60 is used to irradiate tumors
with ( gamma ) -rays
( _{27}^{60} C o longrightarrow_{28}^{60} N i+_{-1}^{0} e+gamma )
Which is responsible for destroying cancer-cells?
A ( cdot gamma- ) rays
В. ( alpha- )rays
( mathbf{c} cdot beta-r a y s )
D. None of these
11
306Wave number of spectral line for a given
transition is ( x c m^{-1} ) for ( H e^{+}, ) then its
value for ( B e^{3+} ) (isoelectronic of ( boldsymbol{H} boldsymbol{e}^{+} ) )
for same transition is:
A ( cdot frac{x}{4} c m^{-1} )
B. ( x mathrm{cm}^{-1} )
( c cdot 4 x c m^{-1} )
D. ( 16 x mathrm{cm}^{-1} )
11
307Electronic configuration of ( G a ) is
A ( cdot[H e] 2 s^{2} 2 p^{1} )
В ( cdot[N e] 3 s^{2} 2 p^{1} )
( mathbf{c} cdot[K r] 4 d^{10} 5 s^{2} 5 p^{1} )
( mathbf{D} cdot[A r] 3 d^{10} 4 s^{2} 4 p^{1} )
11
308The atomic number of chromium is 24
Its electronic configuration in ground
state is ( 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{1} 3 d^{5} )
Chromium atom by losing 3 electrons
form ( mathrm{Cr}^{3+} ) ions. A chromium atom
contains ( 17 % ) more neutron than the
protons. Now answer the following questions
The number of unpaired electrons in ( mathrm{Cr} )
( 3+ ) ions is :
( A cdot 3 )
B. 6
( c cdot 5 )
D.
11
309Which of these are the characteristics
of wave function ( mathbf{Psi} ? )
This question has multiple correct options
A. ( Psi ) must be single valued
в. ( int_{-infty}^{+infty} Psi^{2} d x d y d z=1 )
c. ( Psi ) must be finite and continous
D. ( Psi ) can be discrete
11
310Nuclidic masses of ( _{7}^{14} mathrm{N} ) and ( _{7}^{15} mathrm{N} ) are mixed to give average atomic mass of
14.1. The ratio of ( 14 mathrm{N} ) and ( 15 mathrm{N} ) mixed is : 7 7
11
311The nucleodic masses of ( ^{14} mathrm{N} ) and ( ^{15} mathrm{N} )
are mixed to give atomic mass of 14.1 What is the ratio of the two isotopes as a whole number
11
312If ( boldsymbol{H}_{2}, boldsymbol{H} e, boldsymbol{O}_{2} ) and ( boldsymbol{N}_{2} ) tarvel with same
velocity then the longest de-Brogile wavelength should be associated with:
A ( . H_{2} )
в. ( H e )
( c cdot O_{2} )
D. ( N_{2} )
11
313Two carbon discs of ( 1.0 g ) each are
1.0 ( c m ) apart have equal and opposite charges. If forces of attraction between
them is ( 1.00 times 10^{-5} N ), calculate the
ratio of excess electrons to total atoms
on the negatively charged disc. (permitivity constant is ( 9.0 times 10^{9} N m^{2} )
( left.C^{-2}right) )
A ( cdot 6.68 times 10^{-33} )
В. ( 1.6 times 10^{-14} )
c. ( 4.17 times 10^{-12} )
D. ( 4.17 times 10^{-14} )
11
314Alpha particles are positively charged and contains the nucleus of
atom.
A. ( H e )
в. ( H )
c. ( L i )
D. ( H^{+} )
11
315Suppose the potential energy between electron and proton at a distance r is given by ( -frac{k e^{2}}{3 r^{3}} . ) Use Bohr’s theory to
obtain energy of such a hypothetical
atom
11
316A particle of mass ( M ) at rest decays
into two particles of masses ( m_{1} ) and ( m_{2} )
having non-zero velocities. The ratio of the de-Brogile wavelengths of the particles, ( frac{boldsymbol{I}_{1}}{boldsymbol{I}_{2}} ) is:
A. ( frac{m_{1}}{m_{2}} )
в. ( frac{m_{2}}{m_{1}} )
( c cdot 1: 1 )
D. ( sqrt{frac{m_{2}}{m_{1}}} )
11
317The energy needed to excite a hydrogen atom from its ground state to its third excited state is:
A . ( 12.1 e V )
B. ( 10.2 e V )
c. ( 0.85 e V )
D. ( 12.75 e V )
11
318Calculate the wavelength (in nanometer) associated with a proton moving at ( 1.0 times 10^{3} m s^{-1} )
(Mass of proton= ( 1.67 times 10^{-27} k g ) and
( boldsymbol{h}=mathbf{6 . 6 3} times mathbf{1 0}^{-mathbf{3 4}} boldsymbol{J} boldsymbol{s} )
A. ( 0.40 n m )
в. ( 2.5 n m )
( mathrm{c} .14 .0 mathrm{nm} )
D. ( 0.32 n m )
11
319Q1. (i) Calculate the number of electrons which will together weigh one gram.
(ii) Calculate the mass and charge of one mole of electrons.
11
320Which two orbitals are located along the
axis, not between the axis?
( mathbf{A} cdot d_{x^{2}-y^{2}}, d_{z^{2}} )
B . ( d_{x y}, p_{z} )
( mathbf{c} cdot d_{y z}, p_{x} )
D ( cdot p_{x}, d_{x^{2}-y^{2}} )
11
321What is the colour corresponding to the wavelength of light emitted when the electron in a hydrogen atom undergoes transition from ( n=4 ) to ( n=2 ? )
A. Blue
B. Red
c. Yellow
D. Green
11
322Calculate the wavelength, frequency and wavelength of a light wave whose time period is ( 2.0 times 10^{-10} )sec11
323When a certain metal was irradiated
with a light of ( 8.1 times 10^{16} ) Hz frequency,
the photoelectron emitted had 1.5 times the kinetic energy as did the photoelectrons emitted when the same metal was irradiated with light ( 5.8 times )
( 10^{16} mathrm{Hz} ) frequency. If the same metal is
irradiated with light of 3.846 nm
wavelength,what will be the energy of the photoelectron emitted?
A ( .1 .8 times 10^{2} e V )
В. ( 3.65 times 10^{-17} J )
c. ( 2.28 times 10^{2} e V )
D. ( 4.37 times 10^{-17} J )
11
324How many nucleons are present in phosphorous?
A . 15
B. 16
c. 30
D. 31
11
325Which of the following is not true for atomic number?
A. It indicates the number of protons in the nucleus
B. It is represented usually by z
c. It is identical with the mass number
D. It is constant for a given element
11
326Write the electronic configuration of the following elements
(a) Sulphur ( (mathrm{Z}=16) )
(b) Krypton ( (z=36) )
11
327For which of the following orbital wave function does not change from positive to negative at any distance from
nucleus?
A . ( 1 s )
в. ( 2 p )
c. ( 2 s )
D. ( 3 d )
11
328The total energy of an electron in the ground state of the hydrogen atom is
-13.6 eV. The kinetic energy of an
electron in the first excited state is:
( mathbf{A} cdot 1.7 mathrm{eV} )
B. 3.4 ev
c. 6.8 ev
D. 13.6 ev
11
3295. de Broglie equation is
hv
mo
(a) 2 =
(b) 2 =
(c) 2 =
(d) a = hmo
mn
mv
TL1
11
11
330In Rutherford’s ( alpha ) -particle scattering
experiment, a very small fraction of ( alpha )
particles were deflected by ( 180^{circ} . ) What did the conclude from this observation?
A. All the positive charge and mass of the atom occupy very little space.
B. Most of the space inside the atom is empty
c. All the positive charge and mass of the atom were concentrated in a very small volume.
D. Both A and B
11
331Q. 15 For the electrons of oxygen atom, which of the following statements is
correct?
(a) Zeff for an electron in a 2s orbital is the same as Zef for an electron in a 2p orbital
(b) An electron in the 2s orbital has the same energy as an electron in the 2p orbital
(c) Zeff for an electron in 1s orbital is the same as Zeff for an electron in a 2s orbital
(d) The two electrons present in the 2s orbital have spin quantum numbers m, but
of opposite sign
11
332By using the above informations define the electronic configuration of ( S ) atom.
A ( cdot 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{4} )
B . ( 1 s^{2} 1 p^{6} d^{6} 2 s^{2} )
c. ( 1 s^{2} 1 p^{6} 1 d^{10} )
D. ( 1 s^{2} 1 p^{6} 2 p^{6} 2 d^{2} )
11
333Nodal plane is found in which orbital?
A ( . n=2, l=0 )
B. ( n=3, l=0 )
c. ( n=2, l=1 )
D. ( n=1, l=0 )
11
334The emission spectra of atoms in the gaseous phase do not show a continuous spread of wavelength from red to violet, rather they emit light only at specific wavelengths with dark
spaces between them. Such spectra is/are called:
A. line spectra
B. atomic spectra
c. both ( (A) ) and ( (B) )
D. none of these
11
335The hydrogen-like species ( L i^{2+} ) is in a
spherically symmetric state ( S_{1} ) with one
radial node and its energy is equal to the ground state energy of the hydrogen atom.

The energy of the state ( S_{2}( ) next state ) in units of the hydrogen atom ground state energy is:
A . 7.5
в. 1.50
c. 2.25
D. 4.50

11
336A sample of water is vaporized and tested in a mass spectrometer. There are 3 isotopes of hydrogen, ( 1 H,^{2} H ) and
3. H. There are 2 isotopes of oxygen, ( ^{15} boldsymbol{O} ) and ( ^{16} ) O.

How many peaks would be expected to be found on the mass spectrum?
A . 3
B. 4
( c .5 )
D. 6

11
337Consider the outermost electronic
configuration of silicon as follow:
( [N e] 3 s^{2} 3 p^{2} )
The given electronic configuration follows:
A. Aufbau’s principle
B. Paul’s rule
c. Hund’s rule
D. All of the above
11
338The transition of electron in H-atom that
will emit maximum energy is :
A ( cdot n_{3} rightarrow n_{2} )
В . ( n_{4} rightarrow n_{3} )
( mathbf{c} cdot n_{5} rightarrow n_{4} )
D. all have same energy
11
339De-Broglie relation describes the relationship of wavelength of an electron with:
A . mass
B. energy
c. momentum
D. charge
11
340Calculate the number of neutrons in
( 18 m L ) of water. (Density of water ( =1 ) ).
11
341( L i^{2+} ) ion is in the excited state with
wave function of its electron being
denoted by the symbol ( Psi_{3,1,0} ). How many radiations of different wavelength will
this ( L i^{2+} ) ion will emit upon de-
excitation?
A. zer
B. 6
( c )
( D )
11
342During ( beta ) -decay, the mass of atomic
nucleus:
A. decreases by 1 unit
B. increases by 1 unitt
c. decreases by 2 units
D. remains unaffected
11
343If Hund’s rule is not followed, magnetic
moment if ( mathrm{Fe}^{2+} ) is:
( A cdot O )
в. ( frac{h}{2 pi} )
( c cdot frac{3 h}{2 pi} )
D. ( frac{sqrt{3} h}{4 pi} )
11
344State True or False.
Carbon-14 dating is used to determine the age of once living material
A. True
B. False
11
345Define atomic mass unit.11
346suppose that a hypothetical atom gives a red, green,blue and violet line spectrum. Which jump according to figure would give off the red spectral
ine
A ( .3 rightarrow 1 )
В . ( 2 rightarrow 1 )
( c cdot 4 rightarrow 1 )
D. ( 3 rightarrow 2 )
11
347Calculate the velocity of an electron placed in the third orbit of hydrogen atom. Also calculate the number of
revolutions per second that this electron mkaes around the nucleus.
11
348Which of the following is isoelectronic
pair?
A. ( C N^{-}, O_{3} )
в. ( C l O_{2}, B r F_{2} )
( mathrm{c} cdot mathrm{BrO}_{2}^{-}, mathrm{BrF}_{2}^{+} )
D. ( I C l_{2}, C l O_{3} )
11
349Q.44 Match the following rules with their statements.
Rules
Statements
A Hund’s Rule
1. No two electrons in an atom can have the same set
of four quantum numbers.
B. Aufbau Principle
2. Half-filled and completely filled orbitals have extra
stability
C Pauli Exclusion Principle 3. Pairing of electrons in the orbitals belonging to the
same subshell does not take place until each orbital
is singly occupied.
D. Heisenberg’s Uncertainty 4. It is impossible to determine the exact position and
Principle
exact momentum of a subatomic particle
simultaneously.
5. In the ground state of atoms, orbitals are filled in the
order of their increasing energies.
11
350Which of the following ions is NOT isoelectronic to a noble gas?
A ( . A l^{3} )
в. ( K^{+} )
( c cdot B r^{-} )
D. ( C o^{2} )
11
351When alpha particles are sent through a thin metal foil, most of them go straight through the foil because:
A. Alpha particles are much heavier than electrons
B. Alpha particles are positively charged.
c. Most part of the atom is empty
D. Alpha particles move with the high velocity
11
352Lightest isotope in the periodic table is:
A. tritium
B. deuterium
c. protium
D. none of these
11
353Q3. With what velocity must an electron travel so that its momentum is equal to that of a photon
of wavelength = 5200 A?
11
354What is the frequency of light emitted when an electron in a hydrogen atom jumps from 2nd orbit to 1st orbit?11
355Q. 29 An atom having atomic mass number 13 has 7 neutrons. What is the
atomic number of the atom?
11
356What do you call the compounds having the same molecular formula but
different structural arrangements of atoms?
11
357What is the frequency of photon whose
momentum is ( 1.1 times 10^{-23} k g m s^{-2} ? )
( mathbf{A} cdot 5 times 10^{13} H z )
В. ( 5 times 10^{17} mathrm{Hz} )
c. ( 0.5 times 10^{18} mathrm{Hz} )
D . ( 5 times 10^{18} mathrm{Hz} )
11
358Heisenberg’s uncertainty principle rules out the exact simultaneous
measurement of :
A. probability and intensity
B. energy and velocity
D. position and velocity
11
359Analyze the mass spectrum graph.
Calculate the average atomic mass of
the unknown element:
( A cdot 10.2 a m )
B. 10.5 amu
D. 11.0 amu
11
360Atomic number of element
is 19
( mathbf{A} cdot M g )
в. ( K )
( c . A r )
D. ( C a )
11
361The compound in which cation is
isoelectronic with anion is:
A . ( N a C l )
в. ( C s F )
c. ( N a I )
D. ( K_{2} )
11
362The energy of an electron in second Bohr
orbit of hydrogen atom is:
A. ( -5.44 times 10^{-19} ) ev
B . – 5.44 ( times 10^{-19} ) cal
c. ( -5.44 times 10^{-19} mathrm{kJ} )
D. – ( -5.44 times 10^{-19} ) 」
11
363Isotopes of an element have:
A. same physical properties
B. different chemical properties
C. different no. of neutrons
D. different atomic number
11
364If nucleons in an excited state fall to a
lower energy level, energy is emitted as
A. ( alpha- )rays
B. ( beta- )rays
c. ( gamma- ) rays
D. ( X- ) rays
11
365The minimum energy required for the photo-emission of from the surface of
metal is ( 4.95 times 10^{-19} ) J. Calculate the
critical frequency and the
corresponding wavelength of the photon required to eject the electron.
11
366The mass number is same as
A. atomic mass number
B. molecular mass number
( c . ) both a and ( b )
D. None of the above
11
367The valence configuration of a transition element is ( (n-1) d^{1 rightarrow 10} n s^{1 rightarrow 2} )
The impossible values of ( n ) are:
( A cdot 4,5 ) and 6
B. 1 and 2
c. 2,4 and 6
D. 1,2 and 3
11
368Which of the following parameters are the same for all
hydrogen-like atoms and ions in their ground states?
(b) Speed of the electron
(c) Energy of the atom
(d) Orbital angular momentum of the electron
11
369Which of the following statements is
not correct about the characteristics of
cathode rays?
A. They starts from the cathode and move towards the anode
B. They travel in straight line in the absence of an external electrical or magnetic field
C. Characteristics of cathode rays do not depend upon the material of electrodes in cathode ray tube
D. characteristics of cathode rays depend upon the nature of gas present in the cathode ray tube
11
370Which of the following statements is correct for an electron having azimuthal
quantum number ( l=2 ? )
A. The electron may be in the lowest energy shell
B. The electron is in a spherical orbital
C . The electron must have spin ( m_{s}=+frac{1}{2} )
D. None
11
37174. A hydrogen atom is in an excited state of principle
quantum number n. It emits a photon of wavelength
when it returns to the ground state. The value of n is
Ta(R-1)
(a) VaR(AR-1) (b) /
VaR
AR
(C)
(d)
(R-1)
VaR-1
11
372The value of Planck’s constant
is
( mathbf{A} cdot 6.627 times 10^{-34} )joulesec.
B. ( 6.083 times 10^{-34} ) joulesec.
c. ( 6.627 times 10^{-27} ) joulesec.
D. ( 6.627 times 10^{-30} ) joulesec.
11
373A single electron ion has nuclear charge
( +Z e ) where ( Z ) is atomic number and ( e )
is electronic charge. It requires ( 16.52 e V ) to excite the electron from the
second Bohr orbit. Find
(a) The atomic number of element?
(b) The energy required for transition of electron from first to third orbit??
(c) Wavelength of photon required to remove electron from first Bohr orbit to
infinity?
(d) The kinetic energy of electron in first
Bohr orbit?
11
374Outer electronic configurations of
( boldsymbol{K}, boldsymbol{C u}, ) and ( boldsymbol{C r} ) are respectively :
A ( cdot 4 s^{1}, 3 d^{10}, 3 d^{5} )
B . ( 4 s^{2}, 3 d^{10}, 3 d^{4} )
c. ( 4 s^{1}, 3 d^{9}, 3 d^{4} )
D・ ( 4 s^{2}, 3 d^{9}, 3 d^{4} )
11
375Element with electronic configuration ( 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} ) is a
A . metal
B. non-metal
c. metalloid
D. inert gas
11
376The ground state energy of hydrogen atom is ( -13.6 e V . ) What is the potential
energy of the electron in this state?
A ( .0 mathrm{eV} )
B . -27.2 eV
( mathrm{c} cdot 1 mathrm{eV} )
D. 2 eV
11
377Which of the following statements is
incorrect?
A. The frequency of radiation is inversely proportional to its wavelength
B. Energy of radiation increases with increase in frequency
C. Energy of radiation decreases with increase in wavelength
D. The frequency of radiation is directly proportional to its wavelength
11
378The constant of proportionality which relates energy to the frequency of electromagnetic radiation is Planck’s constant and its value is :
A ( cdot 06.62 times 10^{-34} J s )
B. ( 3.1 times 10^{-31} J s )
( mathbf{c} cdot 6.67 times 10^{23} J s )
D. none of these
11
379The wave number of first line of Balmer
series of hydrogen is ( 15200 mathrm{cm}^{-1} . ) The
wave number of the first Balmer line of
( L i^{2+} ) ion is:
A ( cdot 15,200 mathrm{cm}^{-1} )
В. ( 60,800 mathrm{cm}^{-1} )
c. ( 76,000 mathrm{cm}^{-1} )
D. ( 1,36,800 mathrm{cm}^{-1} )
11
380Which of the following gas when taken in the discharge tube produces maximum specific charge of positive
rays?
A. oxygen
B. Nitrogen
c. Helium
D. Hydrogen
11
381is a definite
path in which the electron revolves
round the nucleus
A. Orbit
B. Circular ring
c. orbital
D. both ( A ) and ( B )
11
382A binary compound between an
unknown element ( E ) and hydrogen contains ( 91.27 % E ) and ( 8.73 % H ) by mass. If the formula of the compound is
( boldsymbol{E}_{3} boldsymbol{H}_{8} . ) Calculate the atomic mass of ( boldsymbol{E} )
11
383The isotopes ( U^{238} ) and ( U^{235} ) occur in nature in the ratio ( 140: 1 . ) Assuming that at the time of earth formation, they were present in equal ratio, the estimated age of the age of earth will be :
(The half-life period of ( U^{238} ) and ( U^{235} ) are ( 4.5 times 10^{9} ) and ( 7.13 times 10^{8} ) years
respectively.)
A. ( 6.04 times 10^{9} ) years
B. ( 6.25 times 10^{9} ) years
c. ( 6.59 times 10^{9} ) years
D. non of these
11
384Calculate the atomic number of the
element that has 12 neutrons and a
mass number of 23
11
385Calculate the frequency of light emitted
for an electron transition from the sixth
to second orbit of the hydrogen atom. In
what region of the spectrum does this
light occur?
11
386The de-Broglie’s wavelength of electron present in first Bohr orbit of ‘H’ atom is :
A ( cdot 0.529 ) a
B ( cdot 4 times 0.529 )
c. ( 2 pi times 0.529 ) 能
D. ( frac{0.529}{2 pi} stackrel{circ}{A} )
11
387Which of the following is the nodal
plane of ( d_{x y} ) orbital? This question has multiple correct options
A. ( x y )
B. YZ
( c cdot z x )
D. All
11
388State whether True or False:
Bohr’s model failed to explain atomic spectra of multi-electron atoms.
A. True
B. False
11
389Uncertainty in position is twice the uncertainty in momentum, uncertainty in velocity is
A. ( sqrt{frac{h}{pi}} )
B. ( frac{1}{2 m} sqrt{frac{b}{pi}} )
( c cdot frac{1}{2 m} sqrt{h} )
D. ( frac{1}{2 sqrt{2 m}} sqrt{frac{h}{pi}} )
11
390Q.10 Which of the following is responsible to rule out the existence of
definite paths or trajectories of electrons?
(a) Pauli’s exclusion principle
(b) Heisenberg’s uncertainty principle
(c) Hund’s rule of maximum multiplicity
(d) Aufbau principle
11
391Chlorine exists in two isotopic forms, ( C l-37 ) and ( C l-35 ) but its atomic
mass is ( 35.5 . ) This indicates the ratio of
( C l-37 ) and ( C l-35 ) is approximately:
A .1: 2
B. 1: 1
c. 1: 3
D. 3: 1
11
392What transition in ( H e^{+} ) ion shall have
the same wave number as the first line
in Balmar series of H atom?
( mathbf{A} cdot 7 rightarrow 5 )
B . ( 5 rightarrow 3 )
( c cdot 6 rightarrow 4 )
( mathbf{D} cdot 4 rightarrow 2 )
11
393In the path of the cathode rays, a tungsten metal is placed in the way. Then the rays produced are:
A. cathode rays
B. anode rays
c. ( x ) -rays
D. UV rays
11
394An atom of radium combines with two
atoms of chlorine to form RaCl
molecule. The radioactivity of ( boldsymbol{R} boldsymbol{a} boldsymbol{C l}_{2} )
will be :
A. zero
B. one-half of the same quantity of Ra
C. one-third of the same quantity of Ra
D. as much as that of the same quantity of Ra
11
395The number of nodal planes ‘5d’ orbital
is:
A . zero
B. one
c. two
D. three
11
39613. The energy of an electron in an excited hydrogen atom is
-3.4 eV. Then, according to Bohr’s Theory, the angular
momentum of this electron, in J s, is
(a) 2.11 x 10-34
(b) 3 x 10-34
(c) 1.055 x 10-34
(d) 0.5 x 10-34
11
397The wave motion of electron in a Bohr’s
orbit of hydrogen is as shown in
diagram. The potential energy of
electron in the given orbit of hydrogen
atom is:
A ( .-3.4 mathrm{eV} )
B. +3.4 ev
( mathbf{c} .-3.02 mathrm{eV} )
D. -1.51 ev
11
398Both isotopes and isobars differ in their chemical properties. (True/False)11
399If ( E_{e}, E_{alpha} ) and ( E_{p} ) represents the kinetic energies of an electron, alpha particle and a proton respectively, each moving with same de Broglie wavelength, then:
A ( cdot E_{e}=E_{alpha}=E_{p} )
В . ( E_{e}>E_{p}>E_{alpha} )
c. ( E_{alpha}>E_{p}>E_{e} )
D. ( E_{e}=E_{p}=E_{alpha} )
11
400What are the draw backs of Bohrs
atomic model? Show that the
circumference of the Bohr orbit for the
hydrogen atom is an integral multiple of the de Broglie wavelength associated with the electron revolving around the
orbit.
11
401Which point does not pertain to Bohr’s model of atom?
A . Angular momentum is an integral multiple of ( h /(2 pi) )
B. The path of the electron is circular
C. Force of attraction towards nucleus = centrifugal force
D. The energy changes are taking place continuously
11
402What is the velocity of electron present in first Bohr orbit of hydrogen atom?
A ( cdot 2.18 times 10^{5} m / s )
B ( cdot 2.18 times 10^{6} m / s )
C ( .2 .18 times 10^{-18} mathrm{m} / mathrm{s} )
D. ( 2.18 times 10^{-9} mathrm{m} / mathrm{s} )
11
403An element has atomic number 17 and
mass number ( 37 . ) There are 17 electrons
outside the nucleus. Find the number of
neutrons in it.
A . 20
B . 21
c. 17
D. 37
11
404A ( 0.66 mathrm{kg} ) ball is moving with a speed of ( 100 mathrm{m} / mathrm{s} . ) The associated wavelength will
be:
( left[h=6.6 times 10^{-34} mathrm{J.s}right] )
A ( cdot 6.6 times 10^{-32} mathrm{m} )
B ( cdot 6.6 times 10^{-34} mathrm{m} )
c. ( 1.0 times 10^{-35} mathrm{m} )
D. ( 1.0 times 10^{-32} mathrm{m} )
11
405(2) Magneul werd UUS
(2) 100
2. In a sodium atom (atomic number = 11 and mass number = 23) and the number of
neutrons is
(a) equal to the number of protons
(b) less than the number of protons
(c) greater than the number of protons
(d) none of these
11
406Two particles ( A ) and ( B ) are in motion. If the wavelength associated with particle ( A ) is ( 5 times 10^{-8} ) m. Calculate the
wavelength associated with particle B if its momentum is half of ( A )
A. ( 5 times 10^{-8} mathrm{m} )
B. ( 10^{-5} mathrm{cm} )
( mathrm{c} cdot 10^{-6} mathrm{cm} )
D. ( 5 times 10^{-8} mathrm{cm} )
11
407( B e^{+3} ) and a proton are accelerated by the same potential,their de-Broglie wavelengths have the ratio:
(Assume mass of proton = mass of
neutron)
( ^{A} cdot frac{1}{2 sqrt{2}} )
B. 1: 4
c. 1: 1
D. ( 1: 3 sqrt{3} )
11
408Which of the following statements concerning Bohr’s model is/are true?
This question has multiple correct options
A. It predicts that probability of electron near nucleus is more
B. Angular momentum of electron in ( H ) atom ( =frac{n h}{2 pi} )
C. It introduces the idea of stationary states
D. It explains line spectrum of hydrogen
11
409Energy levels ( A, B ) and ( C ) of a certain
atoms correspond to increasing values
of every level i.e., ( boldsymbol{E}_{boldsymbol{A}}<boldsymbol{E}_{boldsymbol{B}}<boldsymbol{E}_{boldsymbol{C}} ). If
( lambda_{1}, lambda_{2} ) and ( lambda_{3} ) are the wavelengths of radiations corresponding to the transitions ( C ) to ( B, B ) to ( A ) and ( C ) to
A respectively, then which of the following statements is correct?
B. ( lambda_{3}=frac{lambda_{1} lambda_{2}}{lambda_{1}+lambda_{2}} )
c. ( lambda_{1}+lambda_{2}+lambda_{3}=0 )
D. ( lambda_{3}^{2}=lambda_{1}^{2}+lambda_{2}^{2} )
11
410A certain negative ion ( X^{-2} ) has in its
nucleus 18 neutrons and 18 electrons in
its extra nuclear structure. What is the
mass number of the most abundant
isotope of ‘X’?
A. 35.46
B. 32
( c cdot 36 )
D. 39
11
411Which of the following statement is not
correct regarding cathode rays?
A. Cathode rays originate from the cathoge
B. charge and mass of the particles constituting cathode rays depends upon the nature of the gas
C. Charge and mass of the particles present does not depend the material of the cathode
D. The ratio charge/mass of the particles is much greater than that of anode rays.
11
412The radial part of the Schrodinger wave equation for hydrogen atom is given below:
( gamma(r)=frac{1}{16 sqrt{4} a_{0}^{3 / 2}}(sigma-1)left(sigma^{2}-8 sigma+right. )
( mathbf{1 2}) boldsymbol{theta}^{-boldsymbol{sigma} / mathbf{2}} )
Here, ( a_{0}= ) constant, ( sigma=frac{2 r}{n a_{0}} ) and ( n= )
principal quantum number.
With respect to the above-given data,
select the correct statements.
This question has multiple correct options
A. Distance of the nearest radial node from the nucleus is
( 2 a_{0} )
B. Distance of the farthest radial node from the nucleus
is ( 12 a_{0} )
c. Number of maxima in the curve ( gamma(r) ) vs ( r ) is 4
D. The given equation of ( gamma(r) ) represents ( 4 p ) orbital.
11
413Find the velocity of photo electron
wavelength ( 18 n m ) from stationary ( H e^{+} ) ion in the ground state.
11
414An element X occurs in short period
having configuration ( n s^{2} n p^{1} ). the
formula and nature of its oxide is :
A. ( X O_{3, text { basic }} )
в. ( X O_{3} ),bcidic
c. ( X_{2} O_{3, text { amphoteric }} )
D. ( X_{2} O_{3, text { basic }} )
11
415An electron in ( 2^{n d} ) orbit gains energy
and goes to ( 4^{t h} ) orbit. What are the
differences in angular momentums experienced by the electron due to the transition?
A ( cdot frac{2 h}{pi} )
в. ( frac{h}{2 pi} )
( c cdot frac{h}{pi} )
D. ( frac{3 h}{4 pi} )
11
416Atomic number is denoted by
( A cdot A )
B.
( c cdot z )
D. M
11
417Identify the true statements(s).
This question has multiple correct options
A. The electron density in the xy plane in ( 3 d_{y z} ) orbital is
zero
B. The electron densities in the xy and xz planes in ( 3 d_{y z} )
orbital are zero
C. Paulis principle states that the total wave function of two identical fermions is anti-symmetric with respect to exchange of particles
D. Paulis principle is not obeyed by bosons
11
41818. As the quantum number increases, the difference of en
between conservative energy levels:
(a) decreases
(b) increases
(c) first decreases and then increases
(d) remains the same
11
419When an electron makes transition from
( (n+1) ) state, to ( n ) state the wavelength of
emitted radiations is related to ( n(n>> )
( >1), ) according to ( lambda propto n^{x} ). The value of ( x )
is:
11
420Atoms of two elements ( P ) and ( Q ) have 5
electrons in ( 2^{n d} ) shell and ( 3^{r d} ) shell
respectively. What will be the atomic
numbers of these elements?
A . 4: 15
B. 5: 15
( c cdot 7: 13 )
D. 7: 15
11
421Set of molecules which are
isoelectronic is :
a) ( N_{2} ) and ( C O )
b) ( C O_{2} ) and laughing gas ( left(N_{2} Oright) )
c) ( mathrm{CaO} ) and ( mathrm{MgS} )
d) Benzene and Borazole ( left(B_{3} N_{3} H_{6}right) )
( A cdot a, b, d )
B. b, c, d
c. ( c, d )
D. ( a, b, c, d )
11
422If the de Broglie wavelength of the
electron in ( n^{t h} ) Bohr orbit in a
hydrogenic atom is equal to ( 1.5 pi a_{0}left(a_{0}right. )
is Bohr radius), then the value of ( n / z ) is:
A . 1.0
в. 0.75
c. 0.40
D. 1.50
11
423Protons and neutrons are heavier than
electrons and reside in the center of the
atom, which is called
A. the nucleus
B. the Orbit
c. the orbitals
D. none of the above
11
424Ultraviolet light of ( 6.2 mathrm{eV} ) falls on aluminium surface (work function =
4.2eV). The kinetic energy in joules of the fastest electron emitted is
approximately:
A ( cdot 3 times 10^{-21} )
B . ( 3 times 10^{-19} )
c. ( 3 times 10^{-17} )
D. ( 3 times 10^{-15} )
11
425The radius of an orbit in hydrogen atom is 52.9 A. The angular momentum of the electron in the orbit could be:
A ( cdot frac{5 h}{pi} )
в. ( frac{5 h}{4 pi} )
( c cdot frac{4 h}{2 pi} )
D. ( frac{4 h}{pi} )
11
426A neutral atom has a total of
17 electrons. The electron configuration
in the outermost principle energy level will look closest to:
A ( cdot 1 s^{2}, 2 s^{2}, 2 p^{5} )
B . ( 3 s^{2}, 3 p^{5} )
( mathbf{c} cdot s^{2}, p^{5} )
D. ( s^{2}, p^{8}, d^{7} )
E ( . s, p^{7} )
11
Property of anode rays:
A. Travel in straight lines: They cast a shadow of the objects placed in their way.
B. Produce mechanical effect: A paddle wheel placed in their path starts rotating.
C. Rays are positively charged: Anode rays are deflected towards the negative plate of an electric field.
D. All of the above
11
428The speed of an electron having a
wavelength of ( 10^{-10} m ) is :
A ( cdot 4.24 times 10^{6} m / s )
B . ( 5.25 times 10^{6} mathrm{m} / mathrm{s} )
c. ( 6.25 times 10^{6} m / s )
D. ( 7.25 times 10^{6} mathrm{m} / mathrm{s} )
11
429Number of spectral lines that are emitted by atomic hydrogen excited to
the ( n t h ) energy level is:
A ( cdot frac{1}{2} n(n-1) )
B . ( frac{1}{4} n(n-1) )
c. ( frac{1}{2} n(n+1) )
D ( cdot frac{1}{2} n(n-2) )
11
430Isotopes are the atoms of the different element.
A . True
B. False
11
431Which of the following orbitals is not
cylindrically symmetrical about ( z ) -axis?
( mathbf{A} cdot 3 d_{22} )
в. ( 4 p_{z} )
( c cdot 6 s )
D. ( 3 d_{y_{z}} )
11
432Neutrons are present in all atoms except?
A . не
B.
( c cdot H )
D. Ne
11
433Q. 9 Number of angular nodes for 4d orbital is
(a) 4
(b) 3
(c) 2
(d) 1 an
11
434State True or False.
All living organisms contain carbon-14.
A. True
B. False
11
435Statement I: Ground state electronic
configuration of chromium atom is ( (A r) 4 s^{1} 3 d^{5} )
Statement II: Exchange energy is more wtih ( (boldsymbol{A} boldsymbol{r}) boldsymbol{4} boldsymbol{s}^{1} boldsymbol{3} boldsymbol{d}^{5} ) then ( (boldsymbol{A} boldsymbol{r}) boldsymbol{4} boldsymbol{s}^{2} boldsymbol{3} boldsymbol{d}^{4} )
A. Statement I is true, Statement II is also true Statement is the correct explanation of Statement
B. Statementl is true, statement II is also true:
Statement II is not the correct explanation of Statement
c. statement l is true, Statement II is false
D. Statement I is false, Statement II is true
11
436Spin multiplicity is zero for:
( A )
begin{tabular}{|l|l|l|}
hline ( mathbf{1} ) & ( mathbf{1} ) & ( mathbf{1} ) \
hline
end{tabular}
в. begin{tabular}{|l|l|l|}
hline ( mathbf{1} ) & ( mathbf{1} ) & ( mathbf{j} ) \
hline
end{tabular}
( c )
( left|begin{array}{ll}hline mid & downarrow & downarrowend{array}right| )
D. ( sqrt{ }|V| )
11
437The argument which favours the
particular nature of cathode rays is:
A. they produce fluorescence
B. they travel through vacuum
C. they get deflected by electric and magnetic fields
D. they cast shadows of objects present in their way
11
438If uncertainty in momentum of electron is three times the uncertainty in position, then uncertainty in velocity of electron would be:
A ( cdot frac{1}{4 m} sqrt{frac{h}{3 pi}} )
в. ( frac{1}{3 m} sqrt{frac{h}{pi}} )
c. ( frac{1}{3 m} sqrt{frac{4 pi}{h}} )
D. ( frac{1}{2 m} sqrt{frac{3 h}{pi}} )
11
439Which of the following is the isotone of
( 16^{3^{32}} ? )
( mathbf{A} cdot_{15} P^{31} )
В ( cdot_{7} N^{14} )
( mathbf{c} cdot_{18} A r^{40} )
D ( cdot_{17} C l^{34} )
11
440What is the maximum number of
emission lines when the excited
electron of a ( boldsymbol{H}-boldsymbol{a} boldsymbol{t o m} ) in ( boldsymbol{n}=boldsymbol{6} ) drops
to the ground state?
11
441Which of the properties of the elements is a whole number?
A. Atomic mass
B. Atomic number
D. Atomic volume
11
442Isotopes have same but
different
A. atomic number, mass number
B. atomic mass number, atomic number
C. number of neutrons, atomic number
D. None of these
11
443How many orbitals are present in a ( boldsymbol{p} ) subshell?
( mathbf{A} cdot mathbf{3} )
B.
( c cdot 7 )
D.
11
444An electron has a speed of ( 40 mathrm{m} / mathrm{s} ) accurate up to ( 99.99 % ). what is the uncertainty in locating its position(in
( mathrm{m}) ? )
A. ( 0.0144 mathrm{m} )
B. 0..0258m
c. ( 0.0568 mathrm{m} )
D. 0.0395m
11
445Rutherford’s experiment established
that:
This question has multiple correct options
A. inside the atom there is a heavy positive centre
B. nucleus contains protons and neutrons
C. most of the space in an atom is empty
D. size of nucleus is very small
11
446Identify the correct option amongst the following:
An ( alpha ) particle is :
A. a hydrogen molecule
B. a helium nucleus
c. an electron
D. a proton
11
44707. What is the wavelength for the electron accelerated by 1.0 x 104 volts?11
448The threshold frequency of a metal corresponds to the wavelength of ( x n m ) In two separate experiments ( A ) and ( B ), incident radiations of wavelengths ( 1 / 2 x ) nm and ( 1 / 4 times ) nm respectively are used. The ratio of kinetic energy of the released electrons in experiment B to that in experiment ( A ) is:
( A cdot 1 / 3 )
B. 2
( c cdot 4 )
( D .3 )
E. ( 1 / 2 )
11
449Suppose the potential energy between
electron and proton at a distance r is given by ( -frac{k e^{2}}{r} . ) The value of ( -left(V_{n} / K_{n}right) ) is (Use Bohr’s theory)
11
450In the third energy level, the number of orbtials are:
A. 7
B. 8
( c cdot 9 )
( D )
11
451A compound has the molecular formula
( X_{4} O_{6} . ) If 10 g of ( X_{4} O_{6} ) has 5.72 g ( X, ) then
the atomic mass of ( X ) is :
A . 32 amu
B. 64 amu
c. 67 amu
D. 98 amu
11
452The orbital angular momentum of an electron revolving in a p-orbital is :
A . zero
в. ( frac{h}{sqrt{2} pi} )
( c cdot frac{h}{2 pi} )
D. ( frac{1}{2} frac{h}{2 pi} )
11
453Which of the following is the parent element of the element ( frac{102}{20} Omega ) if it is
formed as a result of ( 3 alpha ) and ( 2 beta^{-} )
decays?
A ( cdot frac{90}{16} Gamma )
B . ( frac{114}{24} Phi )
( mathrm{c} cdot_{28}^{114} mathrm{Theta} )
D. ( _{8}^{12} Delta+_{12}^{90} Xi )
11
454The uncertainty in position and velocity of the particle are ( 0.1 n m ) and ( 5.27 times )
( 10^{-24} m s^{-1} ) respectively then find the
mass of the particle ( (boldsymbol{h}=mathbf{6 . 6 2 5} times ) ( 10^{-34} J s^{-1} )
11
455The wave length of an electron wave is inversely proportional to and
A. mass, density
B. mass, velocity
c. mass, frequency
D. none of these
11
456The wave number of the first line of
Balmer series of H atom is ( 15200 mathrm{Cm}^{-1} )
What is the wave number of the first
line of Balmer series of ( L i^{2+} ) ion?
A. ( 15200 mathrm{Cm}^{-1} )
B. ( 6080 mathrm{Cm}^{-1} )
c. ( 76000 C m^{-1} )
D. ( 136800 C m^{-1} )
11
457In a hydrogen atom, an electronjumps from the second orbit to the first orbit
Find out
The wavelength of the radiation is :
A ( cdot 1.325 times 10^{3} mathrm{A} )
в. ( 2.430 times 10^{3} ) А
c. ( 1.215 times 10^{3} ) A
D. ( 2.255 times 10^{3} ) A
11
458When an electron makes a transition
from ( (n+1) ) state to ( n ) state, the
frequency of emitted radiations is related to n according to ( (n>>1) )
( A cdot v alpha n^{-3} )
B. ( v alpha n^{2} )
c. ( v alpha n^{3} )
D. ( v alpha ) n ( ^{frac{2}{3}} )
11
459Which of the following statements
regarding orbitals is false?
A. ( 1 s ) orbital has one nodal region.
B. ( 2 s ) orbital is spherical with one nodal region.
C ( .2 p_{x} ) orbital is dumb bell with one nodal plane.
D. ( 3 d_{x y} ) orbital has two nodal planes.
11
4609. Which one of the following is isoelectronic with Ne?
(b) Mg2+
(c) A1+
(a) N3-
(d) all of the above
11
461These ions differ in their number of
electrons by eight :
A. ( M g^{+} ) and ( F^{+} )
B. ( L i^{+} ) and ( N e )
( c cdot O^{2-} ) and ( O^{-} )
D. ( N ) and ( P^{3-} )
E ( cdot C a^{2+} ) and ( C l )
11
462The kinetic energy of electrons ejected by using light having frequency equal to threshold frequency ( left(nu_{0}right) ) is:
A ( . h v_{0} )
B. almostzero
c. very large
D. ( h / v_{0} )
11
463One of the fundamental particles is missing in one of the isotopes. Then particle and isotope are respectively:
A. neutron, protium
B. neutron, tritium
c. proton, protium
D. electron, tritium
11
464If an electron jumps from orbit ( A ) to
orbit ( B ) it loses energy while when it jumps from ( C ) to ( B ) it gains energy.
Arrange the orbits in the increasing order of distance from the nucleus.
A. ( A<B<C )
B. ( C<A<B )
c. ( C<B<A )
D. ( A<C<B )
11
465What transition the hydrogen spectrum would have the same wavelength as the Balmer transition ( n=4 ) to ( n=2 ) of
( boldsymbol{H} boldsymbol{e}^{+} ) spectrum?
A ( cdot n_{1}=3, n_{2}=6 )
в. ( n_{1}=2, n_{2}=4 )
c. ( n_{1}=1, n_{2}=2 )
D ( cdot n_{1}=1, n_{2}=4 )
11
466ov. An electron in a Bohr orbit of hydrogen atom with
the quantum number ny has an angular momentum
4.2176 x 10-34 kg ms. If the electron drops from this
level to the next lower level, the wavelength of this line is
(a) 18 nm
(b) 187.6 pm
(c) 1876 Å
(d) 1.876 x 104 Å
11
467The energy of the electron in the first orbit of ( boldsymbol{H} boldsymbol{e}^{-} ) is ( -mathbf{8 7 1 . 6} times mathbf{1 0}^{-mathbf{2 0}} quad boldsymbol{J} . ) The
energy of the electron in the first orbit of hydrogen would be:
( begin{array}{ll}text { A } . & -871.6 times 10^{-20}end{array} )
B . ( -435 times 10^{-20} J )
c. ( -217.9 times 10^{-20} mathrm{J} )
D. – ( 108.9 times 10^{-20} mathrm{J} )
11
468The absolute charge of the electron
is
A ( cdot 1.1 times 10^{11} mathrm{C} )
B . ( 1.6 times 10^{14} mathrm{C} )
c. ( 1.6 times 10^{-19} mathrm{c} )
D. ( 6.0 times 10^{-21} mathrm{c} )
11
46919. The ratio of the speed of the electron in the first Bohr
of hydrogen and the speed of light is equal to (where
and c have their usual meanings in cgs system)
(a) 27thcle
(b) erh/21c
(c) e²cl2rth
(d) 2ne²lhc
Liinol auntum
11
4709. In Bohr’s model of hydrogen atom, let PE represent
potential energy and TE the total energy. In going to a
higher orbit,
(a) PE increases, TE decreases
(b) PE decreases, TE increases
(C) PE increases, TE increases
(d) PE decreases, TE decreases
11
471Which statement is inconsistent with
the concept of isotopes of the same element?
A. Isotopes have the same number of protons
B. Isotopes have the same atomic number
c. Isotopes differ in mass number
D. Isotopes differ in number of neutrons present
E. Isotopes differ in their nuclear charge
11
472Q1. The uncertainty in the position of a moving bullet of mass 10 g is 10% m. Calculate the
uncertainty in its velocity?
11
473Answer the following questions for Zn
atom:

How many electrons have ( n+m=3 ? )

11
This question has multiple correct options
A. mass number can increase only
B. atomic number can increase or decrease
C ( . p / n ) can increase or decrease
D. number of protons can increase or decrease
11
475Give reason for the following:
The physical properties of isotopes of the same element are not identical
11
476Rutherford in his atomic model could
not explain behaviour of :
A. electrons
B. protons
c. neutrons
D. neutrino
11
477Which of the following configurations represents the most electronegative
element?
A ( cdot 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{1} )
B ( cdot 1 s^{2} 2 s^{2} 2 p^{5} )
C ( cdot 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{5} )
D ( cdot 1 s^{2} 2 s^{2} 2 p^{4} )
11
478The probability of finding an electron in
( a d_{x y} ) orbital is maximum:
A. parallel to x-axis
B. parallel to y-axis
c. parallel to x and y-axis
D. at an angle of ( 45^{0} ) from ( x ) and ( y ) axis
11
479The relative atomic mass of an element ( A ) is ( 16.2 . ) There are two isotopes ( _{8}^{16} A ) and ( _{8}^{18} A ) of the element. Calculate the percentage of ( _{8}^{16} A ) present in the
element.
A. 90%
в. 60 %
c. ( 45 % )
D. 80%
11
480When the electronjumps from ( n=5 ) to ( n )
= 2 level, the spectral line observed in
the hydrogen spectrum belongs to:
A. Balmer series
B. Lyman series
c. Brackett series
D. Pfund series
11
481In astronomical observations signals observed from the distant stars are
generally weak. If the photon detector
receives a total of ( 3.15 times 10^{-18} ) J from
the radiations of 600 nm. Calculate the
number of photons received by the detector.
A . 20
B. 10
( c cdot 8 )
D.
11
482The probability of finding out an electron at a point within an atom is
proportional to the :
A. Square of the orbital wave function i, e ( psi^{2} )
B. Orbital wave function i.e.
c. Hamiltonian operator i.e.H
D. Principal quantum number i.e.
11
483Bohr’s model explains:
A. the spectrum of hydrogen atom only
B. the spectrum of any atom or ion having one electron only
C. the spectrum of hydrogen molecule
D. the solar spectrum
11
484Suppose that spin quantum number did not exist, such that only one electron could each orbital of a many-
electron atom will have. Now the atomic
number of the noble gas atoms in this
case is:
( A cdot 2 )
B. 10
( c cdot 9 )
D. none
11
485A dye absorbs a photon of wavelength lambda and re-emits the same energy
into two photons of wavelengths of ( lambda_{1} )
and ( lambda_{2} ) respectively. The wavelength
lambda is related with ( lambda_{1} ) and ( lambda_{2} ) as:
( A cdot lambda=frac{lambda_{1}+lambda_{2}}{lambda_{1} lambda_{2}} )
B. ( lambda=frac{lambda_{1} lambda_{2}}{lambda_{1}+lambda_{2}} )
( c cdot lambda=frac{lambda_{1}^{2} lambda_{2}^{2}}{lambda_{1}+lambda_{2}} )
D. ( lambda=frac{lambda_{1} lambda_{2}}{left(lambda_{1}+lambda_{2}right)^{2}} )
11
486Rutherford Model could not explain:
A. maxwell’s theory of elctrodynamics
B. line spectra of atom
C. both ( A ) and ( B )
D. None of these
11
487Matter consist of particles such as
A . ions
B. molecules
c. atoms
D. All of the above
11
488Match List-I with List-II.11
489Electronic configuration of ( M g^{+2} ) is
identical with?
A . Ne
B. Na a
c.
D.
11
490Assertion
Cathode rays get deflected towards the positive plate of electric field.
Reason
Cathode rays consist of negatively charged particles known as electrons.
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.
11
491Less amount of energy is required to
remove s’ electron than ‘p’ electron.
A. True
B. False
11
492The energy required to excite the electron in the atom from ( n=1 ) to ( n= )
2, when the ionization enthalpy of a
hydrogen atom is ( 1.312 times 10^{6} J / ) mol
will be:
(in the unit of ( 10^{5} ) ).
A . 8.53
B. 7.51
c. 8.92
D. 9.86
11
493A ( 2 p ) -orbital is -1 .
A. spherically
B. cylindrically
( c cdot ) not
D. none of these
11
494What atomic number of an element ( boldsymbol{X} )
would have to become so that the ( 4 t h )
orbit around ( X ) would fit inside the 1 st
Bohr orbit of ( boldsymbol{H}- ) atom?
( A cdot 3 )
B. 4
( c cdot 16 )
D. 25
11
495Bohr proposed his atomic model based
on:
A. oil drop experiment
B. planck’s quantum theory
c. ( alpha ) -ray scattering experiment
D. experiments on conduction of gases
11
496a) Explain Heisenberg’s uncertainly principle with mathematical derivation
b) Calculate the wavelength, frequency
and wave number of light wave whose period is ( 2.0 times 10^{-10} ) sec
11
497The frequency of radiation emitted when the electron falls from ( n=4 ) to
( boldsymbol{n}=mathbf{1} ) in a hydrogen atom will be :
( left(text { Given, } boldsymbol{h}=mathbf{6 . 6 2 5} times mathbf{1 0}^{-mathbf{3 4}} mathbf{J s}right): )
A ( cdot 3.08 times 10^{15} s^{-1} )
В. ( 2.00 times 10^{16} s^{-1} )
c. ( 1.54 times 10^{17} s^{-1} )
D. ( 1.03 times 10^{14} s^{-1} )
11
498Which of the following radiations have least effect on both the photographic plate and zinc sulphide screen?
A . ( alpha ) -rays
B. ( beta ) -rays
c. ( gamma ) -rays
D. All have equal effect
11
499All orbitals in d subshell are degenerate under all conditions.
A. True
B. False
11
500State True or False.
The s orbital is spherical in shape.
A. True
B. False
11
501In Millikan’s oil drop experiment, we make use of:
A. Ohm’s law
B. Ampere’s law
c. Stoke’s law
11
502The ratio of energy to frequency of electromagnetic radiation is called:
A. Bohr’s constant
B. Rydberg’s constant
c. Plancks constant
D. Ritz constant
11
503The number of water molecules
differing in molecular mass formed by hydrogen isotopes and ( ^{1} boldsymbol{H},^{2} boldsymbol{H},^{3} boldsymbol{H} ) and
oxygen isotopes ( ^{16} boldsymbol{O},^{17} boldsymbol{O},^{18} boldsymbol{O} ) is
( A cdot 6 )
B. 9
c. 12
D. 18
11
504When the electron of a hydrogen atom jumps from ( n=4 ) to ( n=1 ) state, the
number of spectral lines emitted will
be:
A . 15
B. 6
( c .3 )
( D )
11
505Which among the following is correct
about ( gamma- ) rays ?
A. High energy electrons
B. Low energy electrons
c. High energy electromagnetic waves
D. High energy positrons
11
506Assertion
If the potential difference applied to an electron is made 4 times, the de Broglie wavelength associate halved.
Reason
On making a potential difference 4 times, velocity is doubled and hence ( lambda ) is halved.

Read the above assertion and reason
and choose the correct option regarding
¡t.
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

11
507The probability of finding an electron in an orbital is approximately:
A . 95%
B. 50%
c. 60%
D. 25%
11
508Why the nucleus is positively charged?11
509An electron in ground state absorbs 1.5 times as much energy required to escape from H atom. The wavelength of
electron emitted in ( A^{circ} ) is :
A ( .4 .21 A^{circ} )
B . ( 4.71 A^{circ} )
c. ( 3.52 A^{circ} )
D. ( 3.711 A^{circ} )
11
510What is the maximum number of
emission lines when the excited electron
of an ( mathrm{H} ) atom in ( mathrm{n}=4 ) drops to the ground
state?
A ( cdot 14 )
B. 6
c. 15
D. 10
11
511019. Distinguish between a photon and quantum.11
512The ratio of energies of photons with
wavelengths ( 2000 A^{0} ) and ( 4000 A^{0} ) is:
A ( cdot 1 / 4 )
B. 4
( c cdot 1 / 2 )
D. 2
11
513Maximum number of electrons held in
the d orbitals is :
( A cdot 2 )
B. 6
c. 8
D. 10
E. 14
11
514225. An electron is in one of the 3d orbitals. Give the possible values of n, I and m, for this electron11
515What does ( psi^{2} ) represents in the quantum model of atom?
A. Density of electron
B. Probability of finding the electron
c. volume of electron
D. Distance of electron from Nucleus
11
516Structures of nuclei of three atoms ( A, B ) and ( C ) are given below :
A has 90 protons and 146 neutrons
B has 92 protons and 146 neutrons
C has 90 protons and 148 neutrons Based on the above data, which of these
atoms are isotopes and which are isobars?
A. A and C are isotopes; B and C are isobars
B. A and B are isotopes; A and C are isobars
c. B and C are isobars; A and B are isotopes
D. A and C are isotopes; A and B are isobars
11
517Number of revolution per second made by electron in Bohr orbit is called orbital
frequency. If ( boldsymbol{u}_{n}, boldsymbol{r}_{n}, boldsymbol{E}_{n} ) are velocity,
radius and energy level of ( n ) th orbit respectively?
A ( cdot frac{u_{n}}{2 pi r_{n}} )
B. ( -frac{2 E_{n}}{n h} )
c. ( -frac{2 E_{1}}{n^{3} h} )
D. either of these
11
518Wave no. of a spectral line for a given
transition is ( x mathrm{cm}^{-1} ) for ( H e^{+} ) then its
value for ( B e^{3+} ) for the same transition
is:
A. ( 4 x mathrm{cm}^{-1} )
B. ( x mathrm{cm}^{-1} )
c. ( frac{x}{4} c m^{-1} )
D. ( 2 x mathrm{cm}^{-1} )
11
519A light whose frequency is equal to ( 6 x ) ( 10^{14} H z ) is incident on a metal whose
work function is ( 2 e V )
( left(h=6.63 times 10^{-34} J s, 1 e V=1.6 times 10^{-}right. )
The maximum energy of electrons emitted will be:
A ( .2 .49 e V )
в. ( 4.49 e V )
c. ( 0.49 e V )
D. ( 5.49 e V )
11
520As the principal quantum number increases, the difference of distance of
separation between consecutive energy
levels:
A . Decreases
B. Remains the same
c. Increases
D. Sometimes increases and sometimes decreases
11
521The mass to charge ratio for ( mathbf{A}^{+} ) ions is ( 1.97 times 10^{-7} mathrm{kg} mathrm{C}^{-1} . ) calculate the mass
of A atom
11
522State True or False.
Solutions of Schrodinger equation for ( H ) -atom give the same set of values of
the energy levels as does the Bohr’s theory
A. True
B. False
11
523An atom contains eleven protons. State
its atomic number and the number of
electrons it contains.
( A cdot 12,12 )
B. 12,11
c. 11,11
D. 12, 13
11
524True or False
The radius of energy of Bohr’s orbit is
equal to integral multiples of 0.529
11
525Effective nuclear charge ( left(Z_{e f f}right) ) for ( a ) nucleus of an atom is defined as:
A. Shielding of the outermost shell electrons from the nucleus by the innermost shell electrons
B. The net positive charge experienced by electron from the nucleus
c. The attractive force experienced by the nucleus from electron
D. Screening of positive charge on nucleus by innermost shell electrons
11
526Ratio of time of electron in first and
second orbit of ( boldsymbol{H} ) – atom be:
( mathbf{A} cdot 1: 18 )
B. 1: 8
c. 1: 2
D. 2: 1
11
527Match the items in List 1 with those in
List 2
List 1:Electronic configuration List 2: Total spin
11
528Which letter orbital corresponds to ( l= )
2?
A.
B.
( c cdot d )
D.
E.
11
529Calculate the energy required to excite two litre of hydrogen gas at 1 atom and ( 298 mathrm{k} ) to the first excited state of atomic
hydrogen. The energy for the
disassociation of ( mathrm{H}_{2} ) bond is ( 436 mathrm{kJ} ) mol
( -1 . ) Also calculate the minimum
frequency of photon to break this bond.
A. ( 8.523 times 10^{15} mathrm{Hz} )
В . ( 1.096 times 10^{15} ) Н ( z )
c. ( 1.633 times 10^{15} mathrm{Hz} )
.
D. 2.806 ( times 10^{15} mathrm{Hz} )
11
530write the general electric configure in periodic table.with example11
531Which of the following statement is
incorrect according to Thomson’s model
of an atom?
A. The electrons, in a sphere of positive charge, were like currants (dry fruits) in a spherical Christmas pudding.
B. The positive charge in the atom is spread all over like the red edible part of the watermelon.
C. The electrons are studded in the positively charged sphere, like the seeds in the watermelon.
D. The protons are studded in the positively charged sphere, like the seeds in the watermelon.
11
532The electron configuration for ( C u ) is ( 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{1} 3 d^{10} )
How many inner core electrons does
copper contain?
( mathbf{A} cdot mathbf{1} )
B . 10
c. 18
D. 28
11
533Boron has two stable isotopes, ( 10_{B(19 %)} )
and ( ^{11} mathrm{B}(81 %) . ) The atomic mass that
should appear for boron in the periodic table is
11
534The quantum numbers of ( +1 / 2 ) and
( -1 / 2 ) for the electron spin
represents
A. rotation of electron in clockwise and anticlockwise direction respectively
B. rotation of electron in anticlockwise and clockwise
direction respectively
C. two quantum mechanical states having classical analogue
D. two quantum mechanical states having no classical analogue
11
535UTILL
Q4. On the basis of quantum numbers, justify that the sixth period of the periodic table should
have 32 elements.
in this choll are 6s Af
11
536If the distance between nuclei is ( 2 x )
( 10^{-13}, ) the density of nuclear material
is:
(mass of neuclei ( left.=10^{-27}right) )
( begin{array}{ll}text { A } cdot 3.21 times 10^{-12} & k g / m^{3}end{array} )
В . ( 1.6 times 10^{-3} mathrm{kg} / mathrm{m}^{3} )
D. ( 1 times 10^{17} mathrm{kg} / mathrm{m}^{3} )
11
537Q22. Which of the following are iso-electronic species?
Nat, K+, Mg2+, Ca2+, s?-, Ar.
+
2+
11
538Give any three postulates of Bohr’s theory of atomic model.11
539If the speed of light is ( 3.0 times 10^{8} mathrm{m} s^{-1} )
calculate the distance covered by light
in 2.00 ns.
( A cdot 0.6 m )
B. 0. 3 ( m )
c. ( 0.9 mathrm{m} )
D. 1.2 ( m )
11
540State True or False
Isotopes have a same number of electrons and protons in all atoms.
A. True
B. False
11
541The orientation of electron orbit is
determined by:
( A cdot n )
B. ( l )
( c cdot m )
D.
11
542A single electron system has ionization energy ( 11180 k J ) mol ( ^{-1} ). Find the
number of protons in the nucleus of the
system.
11
543A beam of specific kind of particles of
velocity, ( 2.1 times 10^{7} m / s ) is scattered by
a gold ( (Z=79) ) nuclei. Find out specific charge (charge/mass) of this particle if this distance of closest approach is ( 2.5 times 10^{-14} m ? )
( mathbf{A} cdot 4.84 times 10^{7} C / k g )
B . ( 4.84 times 10^{-7} mathrm{C} / mathrm{kg} )
c. ( 2.42 times 10^{7} mathrm{C} / mathrm{kg} )
( mathbf{D} cdot 3 times 10^{-12} C / k g )
11
544In which of the following is the radius of the first orbit minimum?
A. A Hydrogen atom
B. A tritium atom
C. Triply ionized beryllium
D. Double ionized helium
11
545Which of the following hydrogen like species will have same radius as that of
a Bohr orbit of hydrogen atom?
A ( cdot n=2, L i^{2+} )
B . ( n=2, B e^{3+} )
C ( cdot mathrm{n}=2, mathrm{He}^{+} )
D. ( n=3, L i^{2+} )
11
546The decreasing order of energy for the electrons represented by the following sets of quantum numbers is :
1. ( n=4, l=0, m=0, s=pm 1 / 2 )
( 2 . n=3,1=1, m=1, s=-1 / 2 )
3. ( n=3,1=2, m=0, s=+1 / 2 )
4. ( n=3, l=0, m=0, s=-1 / 2 )
( A cdot 1>2>3>4 )
B ( .2>1>3>4 )
( (-3>1>2>4 )
D. ( 4>3>2>1 )
11
547Anything that influences the valence electrons will affect the chemistry of the element. Which one of the following
factors does not affect the valence
shell?
A. Valence principal quantum number (n)
B. Nuclear charge
c. Nuclear mass
D. Number of core electrons
11
548The total spin resulting from a d ( ^{7} ) configuration is :
( mathbf{A} cdot mathbf{1} )
B. 2
( c cdot 5 / 2 )
D. 3/2
11
549Three different wavelengths of light (1,2 and 3 ) are shined onto the same
sodium metal surface. Light 1 and 2 produced photoelectrons while Light 3 did not produce any photoelectrons.
Light 2 was able to produce photoelectrons with higher velocities
than Light 1
Arrange the lights in order of decreasing wavelength.
( mathbf{A} cdot 3>1>2 )
В. ( 2>1>3 )
c. ( 1>2>3 )
D. ( 3>2>1 )
11
550Q5. Which one Fe3+, Fe2+ is more paramagnetic and why?
3+
11, 12+ aontains
11
551( |psi(x, y, z, t)|^{2} ) represents:
This question has multiple correct options
A. probability of finding the particle in the space
B. probability distribution function
C . stationary state
D. None of these
11
552Match the shell given in List-I with the value of ( l ) given in List-II.11
553Who was the discoverer of neutrons???
A. Ernest Rutherford
B. J. J. Thomson
D. None of the above
11
554The time taken for an electron to
complete one revolution in Bohr orbit of hydrogen atom is :
A ( cdot frac{4 m^{2} pi r^{2}}{n^{2} h^{2}} )
в. ( frac{n^{2} h^{2}}{4 m r^{2}} )
c. ( frac{4 pi^{2} m r^{2}}{n h} )
D. ( frac{n h}{4 pi^{2} m r^{2}} )
11
555The mathematical expression which is true for the uncertainty principle is:
A ( cdot(Delta x)(Delta v) geq frac{h}{4 pi} )
в. ( (Delta E)(Delta x) geq frac{h}{4 pi} )
c. ( (Delta theta)(Delta phi) geq frac{h}{4 pi} )
D. ( (Delta x)(Delta m) geq frac{h}{4 pi} )
11
556Assertion
The density of ( _{6}^{12} mathrm{C} ) nuclide is about
( 1.8 times 10^{17} k g m^{-3} ) to that of water.
Reason
The ratio of density of ( frac{12}{6} ) C nuclide and
water is about ( 1.8 times 10^{14} k g m^{-3} )
A. Assertionis correct but Reasson is wrong
B. Assertion is wrong but Reasson is correct
C. Both Assertion and Reason are correct and Reason is the correct explanation of Assertion
D. Both Assertion and Reason are correct but Reason is not the correct explanation of Assertion
11
557Find the value of wave number ( bar{v} ) in
terms of Rydberg’s constant, when transition of electron takes place between two levels of ( H e^{+} ) ion whose
sum is 4 and difference is 2
( ^{A} cdot frac{8 R}{9} )
в. ( frac{32 R}{9} )
c. ( frac{3 R}{4} )
D. None of these
11
558De-Broglie wavelength of electron in ( n ) th orbit of ( boldsymbol{H}- ) atom is ( (mathbf{3 . 1 8} boldsymbol{pi}) boldsymbol{A} . ) The value
of ( n ) is:
( A cdot 1 )
B . 2
( c cdot 3 )
D. 4
11
559How many electrons in an atom may
have the following quantum numbers:
( boldsymbol{n}=mathbf{4}, boldsymbol{m}_{s}=-frac{mathbf{1}}{mathbf{2}} )
A ( cdot 14 )
B. 16
c. 32
D. 20
11
560To what effect potential a proton beam be subjected to give its protons a wavelength of ( 1 times 10^{-10} mathrm{m} ? )
A. 0.0826 volts
B. 0.0346 volts
c. 0.0567 volts
D. 0.0234 volts
11
561The line spectrum of two elements is
not identical because:
A. they do not have same number of neutrons
B. they have dissimilar mass number
C. they have different energy level schemes
D. they have different number of valence electrons
11
562What would you predict for the atomic number of the noble gas beyond ( boldsymbol{R} boldsymbol{n} ), if
such an element has sufficient stability to be prepared or observed? Assume
that ( g- ) orbitals are still not occupied in the ground state of preceding elements.
11
563Electron has nearly the equal mass as
that of a/an:
A. proton
B. neutron
C. positron
D. ( alpha ) -particle
11
564Nuclei of isotopes differ in:
A. Number of protons
B. Number of neutrons
C. Number of neutrons and protons both
D. None of these
11
565An electron is not deflected on passing
through a certain region because:
This question has multiple correct options
A. there is no magnetic field in that region
B. there is a magnetic field but velocity of the electron is parallel to the direction of magnetic field
C. the electron is a charge less particle
D. none of the above
11
566The density of nucleus is about times the density of atom.
A ( cdot 10^{-14} )
B. ( 10^{12} )
( c cdot 10^{-8} )
D. ( 10^{10} )
11
567The correct set the quantum unpaired electron of chlorine atom is:
A ( cdot n=2,1=1, m_{1}=0 )
B . ( n=2,1=1, m_{1}=1 )
c. ( n=3,1=1, m_{1}=1 )
D. ( n=3,1=0, m_{1}=0 )
11
568Q. 43 Match the quantum numbers with the information provided by these.
Quantum number
Information provided
A. Principal quantum number 1. Orientation of the orbital
B. Azimuthal quantum number 2. Energy and size of orbital
C. Magnetic quantum number 3. Spin of electron
D. Spin quantum number 4. Shape of the orbital
11
569Energy of the electron in H-atom is 1.50
tionss as much as energy as the minimum required for its escape (13.6
ev) from the atom. The energy difference between two energy livels is?
A . 13.6 ev
B. 20.4 ev
c. 6.8 ev
D. 9.07 ev
11
570One reason the Bohr model of the atom
ultimately failed was because it did not explain why?
A. moving electrons have a greater mass.
B. accelerating electrons do not emit electromagnetic radiation.
c. electrons in greater orbits of an atom have greater velocities
D. electrons in the orbits of an atom have negative energies.
11
mechanics. However, it turns out that
the treatment of spin angular momentum is closely analogous to the treatment of orbital
angular momentum.
Spin angular momentum ( = ) ( sqrt{s(s+1)} h )
Orbital angular momentum ( = ) ( sqrt{l(l+1)} h )
Total spin of an atom or ion is a multiple of ( frac{1}{2} . ) Spin multiplicity isa factor to confirm the electronic configuration of
an atom or ion.Spin multiplicity ( = )
( left(2 sum s+1right) )
The orbital angular momentum for a ( 2 p )
electron is:
A ( cdot sqrt{3} h )
в. ( sqrt{6} h )
c. zero
D. ( sqrt{2} frac{h}{2 pi} )
11
572The energy of electron is maximum at:
A. nucleus
B. ground state
C. first excited state
D. infinite distance from the nucleus
11
573The de-Broglie wavelength of a tennis
ball of mass ( 60 g ) moving with a velocity of ( 10 mathrm{m} / mathrm{s} ) is approximately (planck’s
constant, ( boldsymbol{h}=mathbf{6 . 6 3} times mathbf{1 0}^{-mathbf{3 4}} boldsymbol{J}-boldsymbol{s} )
A ( cdot 10^{-33} m )
В. ( 10^{-31} ) m
c. ( 10^{-16} m )
D. ( 10^{-25} mathrm{m} )
11
574Which one of the following constitutes a group of the isoelectronic species?
A ( cdot C_{2}^{2-}, O_{2}^{-}, C O, N O )
B. ( N O^{-}, C_{2}^{2-}, C N^{-}, N_{2} )
c. ( C N^{-}, N_{2}, C O, C_{2}^{2} )
D. ( N_{2}, O_{2}^{-}, N O^{-}, C O )
11
575L shell has how many subshell?
( A cdot 1 )
B. 2
( c cdot 3 )
D. 4
11
576Mass spectrograph helps in the detection of isotopes because they:
A. have different atomic masses
B. have same number of electrons
c. have same atomic number
D. have same atomic masses
11
577( begin{array}{ll}text { List – I } & text { List – II } \ text { A) Velocity of light } & text { 1) Energy }end{array} ) A) Velocity of light
B) Plank’s constant Energy particle
2) Energy packet
c) Wavenumber
D)
The correct match is:
( A cdot A-2, B-3, C-4, D-5 )
B. A-1, B-2, C-3. D-4
C. ( A-2, B-4, C-5, D-1 )
D. A-3, B-4, C-5, D-1,2
11
578The number of spectral line obtained in
Bohr spectrum of hydrogen atom when an electron is excited from ground level to 5 th orbit is :
A . 10
B. 5
( c cdot 8 )
D. 15
11
579Can you locate the electron within
( mathbf{0 . 0 0 5 n m ?} )
11
580Obtain an expression for the frequency of radiation emitted when a hydrogen
atom de-excites from level n to level ( left(n_{1}right. )
For large ( n ), show that this frequency equals the classical frequency of revolution of the electron in the orbit.
11
581Assertion: K-shell electron capture is detected by analyzing the wavelength of X-ray emitted. Reason: The wavelength of the X-ray is characteristic of the daughter element and not the parent element.
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
11
582The energy of an electron in the first Bohr orbit is -13.6 ev then find the energy
of ( H e^{+} ) in the same Bohr orbit.
A. 27.2 ev
B. -27.2 ev
c. 54.4 ev
D. – 54.4 ev
11
583The mass number of nucleus is:
A. Sometimes equal to its atomic number
B. Sometimes less than and sometimes more than its
atomic number
C. Always less than its atomic number
D. Always more than its atomic number
11
584CONCOUVE
24. If the intensity of radiation incident on a photocell be
increased four times, then the number of photoelectrons
and the energy of photoelectrons emitted respectively
become
(a) four times, doubled
(b) doubled, remains unchanged
(c) remains unchanged, doubled
(d) four times, remains unchanged
11
585The central equation of the quantum theory is the Schrodinger equation. If true enter 1 , else enter 0 .11
586The configuration ( 1 s^{2} 2 s^{2} 2 p^{5} 3 s^{1} ) shows
the :
A. ground state of the fluorine atom
B. excited state of the fluorine atom
c. excited state of the neon atom
D. excited state of ( 0_{2}^{-} ) ion
11
587Suppose that a hypothetical atom gives
a red, green, blue and violet line
spectrum. Which jump according to the
figure would give off the red spectral
line?
( A cdot 3 rightarrow 1 )
B ( .2 rightarrow 1 )
( c cdot 4 rightarrow 1 )
( D cdot 3 rightarrow 2 )
11
588Everything in the universe is made up of material called as
A . life
B. water
c. matter
D. None of the above
11
589An electron is accelerated to one-tenth
the velocity of light. Suppose its velocity can be measured with a precision of ( 1 % ) what must be the uncertainty in position?
A. ( 2.13 times 10^{-10} )
B . ( 1.93 times 10^{-10} )
c. ( 3.85 times 10^{-10} )
D. ( 1.52 times 10^{-10} )
11
590Number of photons emitted in 10 hours
by ( 60 mathrm{W} ) sodium lamp is ( left(lambda=5983 A^{circ}right) )
A. ( 6.40 times 10^{22} )
B. ( 6.40 times 10^{24} )
c. ( 4.60 times 10^{22} )
D. ( 4.60 times 10^{42} )
11
591What is ratio of time periods ( left(T_{1} / T_{2}right) ) in
second orbit of hydrogen atom to third orbit of ( boldsymbol{H} boldsymbol{e}^{+} ) ion?
( A cdot frac{8}{27} )
в. ( frac{32}{27} )
c. ( frac{27}{32} )
D. ( frac{27}{8} )
11
59244. If 2, and I are the wavelengths of the first members of
the Lyman and Paschen series, respectively, then 2:2 is
(a) 1:3
(b) 1:30
(c) 7:50
(d) 7:108
11
593in the state whose multiplicity is three and the total angular
108. An atom is in the state whose multiplicity is
momentum is ħv 20. What can the corresponding quan
Vhat can the corresponding quantum number L
be equal to?
11
594The excitation energy of first excited
state of a hydrogen like atom is ( 40.8 e V )
Find the energy needed to remove the electron to form the ion.
11
595If ( 1.0 mathrm{g} ) body is traveling along the ( mathrm{x} ) -axis at ( 100 mathrm{cm} mathrm{s}^{-1} ) within error limits of ±1
( mathrm{cm} mathrm{s}^{-1}, ) what is the uncertainty in its
position?
( mathbf{A} cdot 5 times 10^{-30} mathrm{m} )
B. ( 5 times 10^{-31} mathrm{m} )
c. ( 5 times 10^{-20} mathrm{m} )
D. ( 5 times 10^{-10} mathrm{m} )
11
596Assertion
Bohr had to postulate that the electrons in stationary orbits around the nucleus
Reason
According to classical physics all moving electrons radiate.
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
11
597According to Rutherford’s atomic model entire mass of the atom is concentrated
at the
A . electron
B. nucleus
c. proton
D. none of these
11
598The position of ( ldots ldots . . . . ) could not be explained in the plum pudding model.
A. nucleus
B. electrons
c. protons
D. all of the above
11
599Electrons are particles of negligible mass carrying unit negative charge.
A. True
B. False
11
600The ( overrightarrow{boldsymbol{v}} ) for the first emission line of
hydrogen atomic spectrum in the Balmer series with respect to the
Rydberg constant ( boldsymbol{R} ) is:
11
601In the hydrogen atom spectrum
( lambda_{3-1} ) and ( lambda_{2-1} ) represent wavelengths emitted due to transition from second
and first excited states to the ground state respectively. The value of ( frac{lambda_{3-1}}{lambda_{2-1}} ) is :
( mathbf{A} cdot 27 / 32 )
в. ( 32 / 27 )
c. ( 4 / 9 )
D. ( 9 / 4 )
11
602Which of the following is a nuclear process that results in no change in the
mass number and atomic number of a
nuclide?
A. Gamma decay
B. Nuclear fusion
c. Alpha decay
D. Positron emission
E. Nuclear fission
11
603The state ( S_{1} ) is:
A . ( 1 s )
в. ( 2 s )
c. ( 2 p )
D. ( 3 s )
11
604Q. 48 Assertion (A) All isotopes of a given element show the same
chemical behaviour.
Reason (R) The chemical properties of an atom are controlled by the
number of electrons in the atom.
(a) Both A and Rare true and R is the correct explanation of A
(b) Both A and R are true but is not the correct explanation of A
(c) A is true but R is false
(d) Both A and Rare false
11
605The threshold energy of a metal is 10 sV Identify the incorrect option. (E = energy of one photon)
A. If ( E=12 e V ), photoelectric effect occurs
B. If ( E=15 e V ), kinetic energy of electron is more than option (A)
C. If intensity of photon increase but energy remain same, the kinetic energy of photoelectron remain same
D. If intensity of photon increase but energy remain same, the kinetic energy of photoelectron increase
11
606What is the electron configuration for
manganese?
A ( cdot 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{5} )
B . ( [A r] 4 s^{1} )
C ( cdot 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{2} 3 d^{5} )
D. ( 1 s^{2} 2 s^{2} 2 p^{1} )
11
607( C a^{2+} ) is isoelectronic with?
( mathbf{A} cdot M g^{2+} )
в. ( K r )
c. ( A r )
D. ( N a^{+} )
11
608An element has atomic number ( 30 . ) Its
cation has 2 units positive charge. How many protons and electrons are present in the cation?
11
609Complete the given balanced equation and find out the missing term.
( _{6}^{14} C rightarrow_{4}^{10} B e+? )
B . ( _{1}^{0} )
( mathrm{c} cdot_{2}^{4} mathrm{He} )
( D cdot_{0}^{0} )
E ( . quad begin{array}{l}n \ nend{array} )
11
610In a certain Bohr orbit, the total energy
is ( -4.9 e V . ) For this orbit, the kinetic
energy, and potential energy are
respectively:
A. ( 9.8 e V,-4.9 e V )
в. ( 4.9 e V,-9.8 e V )
c. ( 4.9 e V,-4.9 e V )
D. ( 9.8 e V,-9.8 e V )
11
611The wavelength associated with a golf
weighing ( 200 g ) and moving at a speed of
( 5 m / h ) is of the order:
B . ( 10^{-20} m )
( mathbf{c} cdot 10^{-30} m )
D. ( 10^{-40} m )
11
612In the pinwheel galaxy, atomic number of all elements are the same as that on
earth and paulis principle is obeyed
However the shell closest to the nucleus
is saturated with electrons before the
next shell starts to fill and the process
continues this way, also each orbital can accommodate only one electron having ( +frac{1}{2} ) spin. If noble gases are defined as the elements with
completely filled outermost shell, which elements would be the nobel gas in
their periodic table?
A ( . A r )
в. ( S i )
( c . F )
D. Ne
11
613Decrease in atomic number is observed
during:
This question has multiple correct options
A . ( alpha ) -emission
B. ( beta ) -emission
c. Positron emission
D. K-capture
11
614Which one of the following constitutes a group of the isoelectronic species?
A. ( mathrm{CN}^{-}, mathrm{N}_{2}, mathrm{O}_{2}^{2-}, mathrm{C}_{2}^{2-} )
в. ( mathrm{N}_{2}, mathrm{O}_{2}^{-}, mathrm{NO}^{+}, mathrm{CO} )
( mathrm{c} cdot mathrm{C}_{2}^{2-}, mathrm{O}_{2}^{-}, mathrm{CO}, mathrm{NO} )
D. ( mathrm{NO}^{+}, mathrm{C}_{2}^{2-}, mathrm{CN}^{-}, mathrm{N}_{2} )
11
615Rydberg constant is:
A. same for all elements
B. different for different elements
C . a universal constant
D. is different for lighter elements but same for heavier elements
11
616The alpha particles get deflected by :
A. very small amounts
B. very large amount
c. same amount
D. ( 90^{circ} )
11
617Bohr’s atomic model is based on the
following postulates that:
This question has multiple correct options
A. an atom consists of nucleus
B. an electron can rotate only in certain energy levels
C . an electron remains moving with continuous loss of energy
D. None of the above
11
618A ( 0.66 k g ) ball is moving with a speed of
( 100 m / s . ) The associated wavelength
will be:
( left(h=6.6 times 10^{-34} J sright) )
В. ( 6.6 times 10^{-34} m )
c. ( 1 times 10^{-35} m )
D. ( 1 times 10^{-32} )
11
619DI LILIT
2. Which of the following is true when Bohr gave his model
for hydrogen atom?
(a) It was not known that hydrogen lines could be
explained as differences of terms like Rin’ with R
being a constant and n an integer.
(b) It was not known that positive charge is concentrated
in a nucleus of small size.
(c) It was not known that radiant energy occurred in
energy bundles defined by hv with h being a constant
and va frequency.
(d) Bohr knew terms like R/nand in the process of
choosing allowed the orbits to fit them, he got
“angular momentum = n;/21 as a deduction.
11
620The correct set of quantum numbers for the unpaired electron of a chlorine atom is:
A ( cdot 2,0,0,+frac{1}{2} )
в. ( _{2,1,-1,+frac{1}{2}} )
c. ( _{3,1,1, pm} frac{1}{2} )
D. ( _{3,0,0, pm} underline{1} )
11
621Assertion
The ground state electron configuration
orbitals of elemental ( boldsymbol{C u} ) is ( [boldsymbol{A} boldsymbol{r}] boldsymbol{4} boldsymbol{s}^{1} boldsymbol{3} boldsymbol{d}^{1} )
Reason
Completely half-filled and filled dorbital best show special electronic
stabilization
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
11
622Which value of ( n ) and ( k ) suggests about the shape of 3s orbital?
( A cdot 3,2 )
в. 1,1
( c cdot 3,0 )
D. 3,3
11
623Which transition in ( L i^{2+} ) would have the
same wavelength as the ( 2 rightarrow 4 )
transition in ( boldsymbol{H} boldsymbol{e}^{+} ) ion?
( A cdot 4 ) to 6
B. 4 to 3
( c cdot 5 ) to 6
D. 5 to 4
11
624A radioactive nuclide emits ( gamma ) -rays due
to:
A ( . K ) -electron capture
B. nuclear transition from higher to lower energy state
C. presence of greater number of neutrons than protons
D. presence of greater number of protons than neutrons
11
625A hydrogen-like atom in ground state absorbs n photons having the same energy and its emits exactly n photons when electrons transition takes placed. Then, the energy of the absorbed photon
may be :
This question has multiple correct options
A. 91.8 eV
в. 40.8 eV
c. 48.4 eV
D. 54.4 eV
11
626Oil ( A ) is at ( 300^{circ} ) C whereas oil ( B ) is at
( 530^{circ} ) F. Which one is hotter?
A. ( A )
в. ( B )
c. Both are same
D. Can not be predicted
11
62768. The wavelength of radiation required to excite the electron
from the first orbit to the third orbit in a doubly ionized
lithium atom will be
(a) 134.25 Å
(c) 125.5 Å
(c) 113.7 Å
(d) 110 Å
11
628The mass of proton is ( _{—}– ) times the
mass of an electron.
A . 1822
в. 1857
( c cdot 1869 )
D. 1837
11
629Which of the following constitutes a group of isoelectronic species?
A ( cdot C O, N_{2}, O_{2}^{-} )
в. ( N_{2}, C N^{-}, N O^{+} )
( mathrm{c} cdot O_{2}^{-}, N O, C_{2}^{2} )
D. ( C l^{-}, A r, N A^{+} )
E ( cdot S^{2-}, C a^{2+}, C N^{-} )
11
630The velocity of all electromagnetic
radiation is ( x times 10^{8} mathrm{m} mathrm{s}^{-1} )
Value of ( x ) is :
11
631A beam of helium atoms moves with a
velocity of ( 2 times 10^{4} . ) Find the wavelength of particles constituting with the beam
11
632Assertion
In an atom, the velocity of electrons in
the higher orbits keeps on decreasing.
Reason
Velocity of electron in an orbit is inversely proportional to the radius of
the orbit.
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
11
633Assertion
The angular momentum of an electron in an atom is quantized.
Reason
In an atom only those orbits are permitted in which angular momentum of the electron is integral multiple of ( frac{h}{2 pi} ) where ( h ) is a plank’s constant.
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
11
634Match the items in List 1 with those in
List 2
11
635“Electrons can jump from one orbit to
other orbit. They cannot flow from one
orbit to another” Justify.
11
636The fundamental particles present in equal numbers in neutral atoms
(atomic number ( 71) )
are
A. protons and electrons
B. neutrons and electrons
c. protons and neutrons
D. protons and positrons
11
637There is a transition from ( n=1 ) to ( n=2 )
and then ( n=2 ) to ( n=3, ) then:
A. ( Delta E ) values as well as frequency are additive
B. wave length as well as frequency are additive
c. ( Delta E ) values as well as wavelength are additive
D. all of the parameters, ( (Delta E, ) frequency and wave length are additive
11
638An f-shell containing 6 unpaired electrons can exchange:
A. 6 electrons
B. 9 electrons
c. 12 electrons
D. 15 electrons
11
639The total energy of the electron of ( boldsymbol{H} ) atom in the second quantum state is
( -boldsymbol{E}_{2} . ) The total energy of the ( boldsymbol{H} boldsymbol{e}^{+} ) atom in the third quantum state is:
( ^{mathrm{A}} cdot-left(frac{3}{2}right) E_{2} )
в. ( -left(frac{2}{3}right) E_{2} )
c. ( -left(frac{4}{9}right) E_{2} )
D. ( -left(frac{16}{9}right) E_{2} )
11
640Atoms of different elements having the same mass number are known as:
A. isotopes
B. isobars
c. isotones
D. isomers
11
641The wavelength photon obtained by electron transition between two level in
H-atom and singly ionised ( boldsymbol{H} e ) are ( boldsymbol{lambda}_{mathbf{1}} )
and ( lambda_{2} ) respectively, then:
A ( cdot lambda_{2}=lambda_{1} )
B ( cdot lambda_{2}=2 lambda_{1} )
c. ( lambda_{2}=lambda_{1} / 2 )
D. ( lambda_{2}=lambda_{1} / 4 )
11
642If Atom 1 has 19 protons and 22 neutrons and Atom 2 has 20 protons
and 22 neutrons, are these isotopes of the same element?
A. There is not enough information to determine this.
B. No, because they have different numbers of protons.
c. No, because they have the same number of neutrons.
D. Yes, because they have different numbers of protons
E. Yes, because they have the same number of neutrons
11
643Which quantum number is not related with Schrodinger equation?
A. Principal
B. Azimuthal
c. Magnetic
D. spin
11
644Relative molecular mass is the ratio of
A. the average mass of one molecule of an element or compound to of the mass of an atom of carbon-12
B. the average mass of one molecule of an element or compound to one twelfth of the mass of an atom of carbon-12
C. the average mass of one molecule of an element or compound to one fifth of the mass of an atom of carbon-12
D. the average mass of one molecule of an element or compound to one twelfth of the mass of an atom of carbon-16
11
645PICUOU COU
L
OI

Q27. Give the number of electrons in the species : ,,H, and 0,*.
Ang L+
ana
+ – 15
11
646The energy of a hydrogen atom in the ground state is ( 13.6 mathrm{eV} ). The energy of a
( mathrm{He}^{+} ) ion in the first excited state will be:
A . -6.8 ev
B . -13.6 ev
c. – 27.2 ev
D. – 54.4 ev
11
647Which one contains up to ten electrons
from the following?
A . ( 1 s )
B . ( 2 s )
( c cdot 3 s )
D. ( 3 p )
E . ( 3 d )
11
648C-14 has a half life of
A. 11520 yrs
B. 2880 yrs
c. 5760 yrs
D. 17280 yrs
11
649Anode rays are also called as:
A. Cathode Rays
B. Canal Rays
c. ( x ) -rays
D. None of these
11
650From the electronic configuration of the given elements ( boldsymbol{K}, boldsymbol{L}, boldsymbol{M} ) and ( boldsymbol{N}, ) which
one has the highest ionization potential?
( mathbf{A} cdot M=[N e] 3 s^{2} 3 p^{2} )
B . ( L=[N e] 3 s^{2} 3 p^{3} )
C ( cdot K=[N e] 3 s^{2} 3 p^{1} )
D cdot ( N=[A r] 3 d^{10}, 4 s^{2} 4 p^{3} )
11
6516. The angular momentum of an electron in an orbit is
quantized because it is a necessary condition for the
compatibility with
(a) wave nature of electron
(b) particle nature of electron
(c) Pauli’s exclusion behavior
(d) none of these
11
652Which statements concerning Bohr’s
model are true?
This question has multiple correct options
A. Predicts that probability of electron near nucleus is
more
B. Angular momentum of electron in H-atom ( =frac{n h}{2 pi} )
C. Introduces the idea of stationary states
D. Explain line spectrum of hydrogen
11
653The frequency of resulting spectral line, in cycle per seconds is:
A. ( 1.93 times 10^{-11} )
В. ( 2.9 times 10^{16} )
c. ( 1.93 times 10^{11} )
D. ( 2.9 times 10^{-11} )
11
654d) = NUW
26. If a surface has work function of 3.00 eV, the longest
wavelength of light which will cause the emission of
electrons is
(a) 4.8 x 10-7 m (b) 5.99 x 10-7 m
(C) 4.13 x 10-7 m
(d) 6.84 x 10-7 m
11
655The wavelength of light emitted by
electron in ( C^{5+} ) ion during transition from ( n=3 ) to ( n=1 ) is approximately:
A. 2.85 nm
B. 3.6 пт
( c .8 .7 n m )
D. ( 9.8 n m )
11
656The number of electrons in ( 3 d ) orbitals
for element with Atomic number 26 is:
A . 4
B. 6
( c cdot 8 )
D. 10
11
657The Balmer series of hydrogen spectra
lies in:
A. visible region spectra
B. ultra violet spectra
c. infrared region spectra
D. ( gamma ) -rays spectra
11
658Which orbital is represented by wave
function ( Psi_{310} ? )
A ( cdot 3 d_{x y} )
B . ( 3 p_{z} )
( c cdot 4 s )
D. ( 4 d_{z} )
11
659cu CSULT
4. The idea of stationary orbits was first given by
(a) Rutherford (b) JJ. Thomson (C) Niels Bohr
(d) Max Planck
11
660The wavelength of ( beta ) -line of the Balmer
series is ( 4815 A ). What is the
wavelength of ( alpha ) -line of the Balmer
series of the same atom?
11
661The Schrodinger wave equation is based on which nature of electron?
A. wave
B. Particle
c. atomic
D. Both A and E
11
662The spectral lines corresponding to the
radiation emitted by an electron jumping from 6 th, 5 th and 4 th orbits to second orbit belong to:
A. Lyman series
B. Balmer series
c. Paschen series
D. Pfund series
11
663The principal quantum number and
azimuthal quantum number values for the differentiating electron of ‘d’ block
elements are and
11
664The isoelectronic pair is:
A. ( C l_{2} O, I C l_{2} )
в. ( C l_{2}, C l O_{3}^{-} )
( mathbf{c} cdot I F_{2}^{+}, I_{3}^{-} )
D. ( C l O_{2}^{-}, C l F_{2} )
11
665A metal was irradiated by light of frequency ( 3.2 times 10^{15} s^{-1} . ) The
photoelectron produced had its ( mathrm{KE}, 2 ) times the KE of the photoelectron which was produced when the same metal was irradiated with a light of frequency ( 2.0 times 10^{15} s^{-1} . ) What is the ionization
energy of metal?
11
666The atomic masses of ( H e ) and ( N e ) are 4
and 20 amu, respectively. The value of
the de Broglie wavelength of ( H e ) gas at
( -73^{0} C ) is ( ” M^{prime prime} ) times that of the de
Broglie wavelength of ( N e ) at ( 727^{0} C . M )
is:
( mathbf{A} cdot mathbf{5} )
B. 0.2
( c cdot 2 )
D. 0.5
11
667Calculate the wavelength of radiation emitted producing a line in Lyman series, when an electron falls from fourth stationary state in hydrogen ( operatorname{atom}left(boldsymbol{R}_{boldsymbol{H}}=mathbf{1 . 1} times mathbf{1 0}^{mathbf{7}} boldsymbol{m}^{-mathbf{1}}right) . ) If the
answer is ( x times 10^{-8} mathrm{m} ), then find the
value of ( x )
11
668Q. 21 Which of the following statements concerning the quantum numbers are
correct?
(a) Angular quantum number determines the three dimensional shape of the orbital
(b) The principal quantum number determines the orientation and energy of the
orbital
(c) Magnetic quantum number determines the size of the orbital
(d) Spin quantum number of an electron determines the orientation of the spin of
electron relative to the chosen axis
11
669State True or False.
( mathrm{Fe}^{3+} ) is paramagnetic.
A. True
B. False
11
670The electronic configuration of gadolinium (Atomic No.64) is:
( mathbf{A} cdot[X e] 4 f^{3} 5 d^{5} 6 s^{2} )
( mathbf{B} cdot[X e] 4 f^{6} 5 d^{2} 6 d^{2} )
( mathbf{c} cdot[X e] 4 f^{8} 5 d^{9} 6 s^{2} )
( mathbf{D} cdot[X e] 4 f^{7} 5 d^{1} 6 s^{2} )
11
671Q. 2 Which of the following options does not represent ground state electronic
configuration of an atom?
(a) 1s 2s 2p 3s 3p 3 do
4 00 (b) 1s 2s 2p 3s 3p3.dº45
(c) 1s²2s22p 3s 3p%3d045! (d) 1s 2s 2p 3s 3p 3d 4s!
11
672Mark the incorrect relation.
A ( cdot N_{0}=N E^{lambda t} )
B . ( tau=1.44 t_{0.5} )
( ^{mathrm{c}} N=N_{0}left(frac{1}{2}right)^{n} )
D. ( t_{1 / 2}=2.303 lambda log 2 )
11
673Assertion
The magnetic moment of ( M g ) -atom is
more than ( K ) -atom as the former has
two electrons in outermost shell.
Reason
The magnetic moment of ( N ) -atom is
more than magnetic moment of ( O ) -atom
and former has more number of
unpaired electrons.
A. Assertion is correct but Reason is wrong.
B. Assertion is wrong but Reason is correct.
c. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
D. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
11
674The Bohr radius for the hydrogen atom
( boldsymbol{n}=mathbf{1}) ) is approx ( mathbf{0 . 5 3} boldsymbol{A}^{o} . ) The radius for
the first excited state ( (n=2 ) orbit) is
( left(operatorname{in} A^{o}right) )
A . 0.13
B. 1.06
c. 4.77
D. 2.12
11
675PDT 5)
4. Using Aufbau principle, write the ground state electronic configuration of following atoms,
(i) Boron (Z = 5) (ii) Neon (Z = 10), (iii) Aluminium (Z = 13) (iv) Chlorine (Z = 17),
(v) Calcium (Z = 20) (vi) Rubidium (Z = 37)
12.2.1
11
676The atomic weight of an element is 23 and its atomic number is ( 11 . ) The
number of proton, electrons and neutrons respectively, present in the atom of the element are
A. 11,11,12
В. 12,12,11
c. 11,12,11
D. 12,11,12
11
677( boldsymbol{H} ) -atoms in ground state ( (mathbf{1 3 . 6 e V}) ) are excited by monochromatic radiations of
photon of energy ( 12.1 e V ). The number of spectral lines emitted in ( boldsymbol{H} ) -atom will
be:
A . 1
B. 2
( c .3 )
D. 6
11
678The radius of the shortest orbit in a one-
electron system is 18 pm. It may be
A. hydrogen
B. deuterium
( mathrm{c} cdot H^{+} )
D. ( L^{++} )
11
679Mass number is
A. the sum of the total number of protons and neutrons present in the nucleus of an atom.
B. the electrons present in the outermost shell of an
atom.
C. an atom of each element having a definite combining capacity.
D. the total number of protons present in the nucleus of an atom.
11
680We can say that the energy of frequency ( boldsymbol{v} ) is given by ( boldsymbol{E}=boldsymbol{h} boldsymbol{v}, ) where ( boldsymbol{h} ) is
Planck’s constant. The momentum of a photon is ( p=frac{h}{lambda} ) where ( lambda ) is the
wavelength of photon. Then we may conclude that velocity of light is
equal to:
A ( cdotleft(frac{E}{P}right)^{1 / 2} )
в.
c. Ep
D. ( left(frac{E}{P}right)^{2} )
11
681Assertion
( P ) orbital is dumb-bell shaped.
Reason
Electron present in p orbital can have any one of the three values of the magnetic quantum number, i.e 0,+1 or
-1
Read the above assertion and reason
and choose the correct option regarding
¡t.
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
11
682Rutherford’s atomic model could not
explain the stability of atom. How do you account for this?
11
683Formula of Heisenberg uncertainty
principle is:
11
684The uncertainty (in meters) in the position of an insect weighing ( 0.68 g ) and traveling at a velocity of ( 0.85 mathrm{m} / mathrm{s} ) (the uncertainty in the velocity is 0.1 ( m / s), ) is:
A. ( 8 times 10^{-21} mathrm{m} )
В. ( 4 times 10^{-25} mathrm{m} )
c. ( 8 times 10^{-31} m )
D. ( 8 times 10^{-34} m )
11
685According to Bohr theory, the electronic
energy of hydrogen atom in the ( n ) th Bohr orbit is given by,
[
boldsymbol{E}_{boldsymbol{n}}=-frac{boldsymbol{2} mathbf{1} . boldsymbol{7} boldsymbol{6} times mathbf{1 0}^{-19}}{boldsymbol{n}^{2}} boldsymbol{J}
]
Calculate the longest wavelength of light that will be needed to remove an electron from the 2 nd orbit of ( L i^{2+} ) ion.
11
686Q2. Define atomic number, mass number and neutron. How are the three related to each other?
Ana Alami Membaw (). The atomic numher of an element is equal to the number of
11
687What led to the failure of Dalton’s
atomic theory?
A. Discovery of fundamental particle electron inside the atom
B. Discovery of fundamental particle proton inside the atom
c. Discovery of canal rays
D. Both A and B
11
688The force which is responsible for circular motion of electrons around the
nucleus is
A. Van der Waals
B. Electrostatic forces
c. centrifugal and Centripetal
D. Intermolecular forces
11
689Which of the following was not proposed by Thomson?
A. The negative and positive charges are equal in magnitude
B. The electrons revolve around the nucleus in circular paths
C. The electrons are embedded in a positive sphere
D. Atoms are electrically neutral
11
690Atoms with same atomic number and
different mass numbers are called:
A. Isobars
B. Isomers
c. Isotones
D. Isotopes
11
691Total no of lines in Lyman series of ( mathrm{H} ) spectrum will be (where ( n= ) no.of orbits)
( A cdot n )
B. ( n(n-1) / 2 )
( c cdot n-2 )
( D cdot n(n+1) )
11
692Which of the following sets of quantum numbers is correct for an electron in ( 4 f )
orbital?
A ( . n=4, l=3, m=+4, s=+1 / 2 )
в. ( n=4, l=4, m=-4, s=-1 / 2 )
c. ( n=4, l=3, m=+1, s=+1 / 2 )
11
693A naturally occuring sample of copper consists of ( 69.2 % ) of ( ^{63} mathrm{Cu} ) and ( 30.8 % ) of
( ^{65} mathrm{Cu} . ) The relative mass of ( ^{63} mathrm{Cu} ) is 62.93
and that of ( ^{65} mathrm{Cu} ) is ( 64.93 . ) Find the
atomic mass of a naturally occuring sample of copper.
A. 64.348
B. 63.546
c. 64.12
D. none of these
11
694Which of the following is the correct
form of Schrodinger wave equation?
A ( cdot frac{partial^{2} Psi}{partial^{2} x}+frac{partial^{2} Psi}{partial^{2} y}+frac{partial^{2} Psi}{partial^{2} z}+frac{8 pi^{2} m}{h^{2}}(E-V) Psi=0 )
B ( cdot frac{partial^{2} Psi}{partial x^{2}}+frac{partial^{2} Psi}{partial y^{2}}+frac{partial^{2} Psi}{partial z^{2}}+frac{8 pi^{2} m}{h^{2}}(E-V) Psi=0 )
C ( cdot frac{partial Psi^{2}}{partial x^{2}}+frac{partial Psi^{2}}{partial y^{2}}+frac{partial Psi^{2}}{partial z^{2}}+frac{8 pi^{2} m}{h^{2}}(E-V) Psi=0 )
D ( cdot frac{partial^{2} Psi}{partial x^{2}}+frac{partial^{2} Psi}{partial y^{2}}+frac{partial^{2} Psi}{partial z^{2}}+frac{8 pi^{2} m^{2}}{h^{2}}(E-V) Psi=0 )
11
695Assuming ( z- ) axis inter nuclear axis. In
which of the following orbitals overlap to
form ( sigma ) bond
( boldsymbol{s}+boldsymbol{p}_{boldsymbol{x}} )
11
696The uncertainty in momentum of a
particle is ( 3.31 times 10^{-2} mathrm{Kg} ) msec ( ^{-1} )
Calculate uncertainty in its position.
A. ( 6.4 times 10^{-33} m )
m
В. ( 1.6 times 10^{-33} m )
c. ( 3.2 times 10^{-33} m )
D. ( 5 times 10^{-33} m )
E ( .2 .5 times 10^{-33} m )
11
697The value of ( e / m ) of an electron was
measured by :
A. Millikan
B. J.J. Thomson
c. Dalton
D. Rutherford
11
698Which of the following is responsible to
rule out the existance of defence of
definite paths or trajectories of
electrons?
A. Pauli’s exclusion principle
B. Heisenberg’s uncertainty principle
c. Hund’s rule of maximum multiplicity
D. Aufbau principle
11
6999. If the series limit of Lymen series for Hydrogen atom is
equal to the series limit of Balmer series for a hydrogen
like atom, then atomic number of this hydrogen-like atom
will be
(a) 1
(b) 2
(c) 3
(d) 4
11
700is the nuclear process
that transmutes uranium-238 into
thorium-234.
A. Gamma decay
B. Nuclear fusion
c. Alpha decay
D. Positron emission
E. Nuclear fission
11
701An atom has ( x ) energy level, then total
number lines in its spectrum are?
A ( .1+2+3 ldots .(x+1) )
B. ( 1+2+3 ldotsleft(x^{2}right) )
c. ( 1+2+3 ldots .(x-1) )
D. ( (x+1)(x+2)(x+4) )
11
702On the basis of quantum numbers, justify that the sixth period of the periodic table should have 32 elements.11
703It was found that electrons have
negligible mass but have one unit of negative charge. Which of the following
model satisfies this statement??
A. Thomson’s atomic model
B. Goldstein’s atomic model
D. None of the above
11
704Which of the following has negative charge and pairs with opposite spin?
A. Proton
B. Neutron
c. Electron
D. Isotope
E. lon
11
705An electron in an atom undergoes transition in such a way that its kinetic energy changes from ( x ) to ( frac{x}{4}, ) the change in potential energy will be:
A ( cdot+frac{3}{2} x )
B. ( -frac{3}{8} x )
( c cdot+frac{3}{4} x )
D. ( -frac{3}{4} x )
11
706Which is characteristic of unstable
nucleus?
This question has multiple correct options
( mathbf{A} cdot n / p ) ratio is high
B. Low binding energy
C. High packing fraction
D. None of these
11
707For the given orbital in Column I, the
only CORRECT combination for any
hydrogen-like species is
( A cdot(1 vee) )
(iv)
B. (III) (iii) (P)
( c .(11) ) (ii)
(P)
D. (I) (ii) (S)
11
708Assertion
Kinetic energy of photoelectrons increases with increase in the
Reason
The number of photoelectrons ejected increases with increase in intensity of incident radiation.
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
11
709A golf ball has a mass of 40 g, and a speed of ( 45 mathrm{m} / mathrm{s}, ) if speed can be measured within accuracy of ( 2 % ) calculate the uncertainty in the position.
A . ( 1.56 times 10^{-30} )
В. ( 1.46 times 10^{-33} mathrm{m} )
c. ( 1.47 times 10^{-23} mathrm{m} )
D. ( 1.47 times 10^{-30} mathrm{m} )
11
710The isotope of hydrogen which is/are radioactive in nature:
A. protium and deuterium
B. tritium and deuterium
c. only tritium
D. only deuterium
11
711If principal quantum number ( n=5, ) then the total number of orbitals present in a given stationary state is:
A .24
B. 25
( c cdot 26 )
D. 27
11
712A photon of wavelength ( 4400 dot{A} ) is passing through vacuum. The effective mass and momentum of the photon are
respectively?
A ( .5 times 10^{-36} k g, 1.5 times 10^{-27} k g-m / s )
B . ( 5 times 10^{-25} mathrm{kg}^{text {‘ }}, 1.5 times 10^{-26} mathrm{kg}-mathrm{m} / mathrm{s} )
C. Zero, ( 1.5 times 10^{-26} mathrm{kg}-mathrm{m} / mathrm{s} )
D. ( 5 times 10^{-36} ) в ( g ), ( 1.36 times 10^{-43} ) kg ( -m / s )
11
times less than the radius of the atom.
A ( cdot 10^{3} )
B. ( 10^{text {। }} )
( c cdot 10^{5} )
D. ( 10^{2} )
11
714In the degenerate orbitals, unpaired electrons have same spin.
A. True
B. False
11
7155. The diagram shows the
energy levels for an
electron in a certain atom.
Which transition shown
represents the emission
of a photon with the most
energy?
I
(a) II
(c) IV
(d) III
II
I
TYN=1
(b) I
(AIEEE 2005)
11
716The orbital angular momentum of an electron corresponding to ( n=4 ) and
( boldsymbol{m}=-mathbf{3} ) is:
A . 0
в. ( frac{h}{sqrt{2} pi} )
c. ( frac{sqrt{6} h}{2 pi} )
D. ( frac{sqrt{3} h}{pi} )
11
717Define Aufbau Principle11
718In an atom two electrons move around the nucleus in circular orbits of radii
and ( 4 mathrm{R} ). The ratio of the time taken by them to complete one revolution is:
A .1: 4
B . 4: 1
c. 1: 8
D. 8: 7
11
719The number of unpaired electrons in a
chromic ion ( left.C r^{3+} text { (atomic number } 24right) )
is:
( A cdot 6 )
B. 4
( c .3 )
D.
11
720ULIWA
Q1. (a) What is the limitations of Rutherford model of atoms?
(b) How has Bohr’s theory helped in calculating the energy of hydrogen electron in different
energy levels?
11
721Which one of the following sets of ions represents a collection of isoelectronics
species?
A. ( K^{+}, C l^{-}, C a^{2+} )
B. ( B a^{2+}, S r^{2+}, K^{+}, C a^{2+} )
c. ( N^{3}-, O^{2-}, C a^{2+}, S^{2} )
D. ( L i^{+}, N a^{+}, M g^{2+}, C a^{2+} )
11
722A formula analogous to the Rydberg formula applies to the series of spectral
lines which arise from transitions from
higher energy level to the lower energy
level of hydrogen atom.
A muonic hydrogen atom is like a hydrogen atom in which the electron is
replaced by a heavier particle, the muon’. The mass of the muon is about
207 times the mass of an electron,
while the charge remains same as that
of the electron. Rydberg formula for hydrogen atom is:
( frac{1}{lambda}= )
( boldsymbol{R}_{boldsymbol{H}}left[frac{mathbf{1}}{boldsymbol{n}_{mathbf{1}}^{2}}-frac{mathbf{1}}{boldsymbol{n}_{2}^{2}}right]left(boldsymbol{R}_{boldsymbol{H}}=mathbf{1 0 9 6 7 8 c m}^{-1}right) )
Radius of first Bohr orbit of muonic
hydrogen atom is
A ( cdot frac{0.259}{207} dot{A} )
B. ( frac{0.529}{207} ),
c. ( 0.529 times 207 hat{A} )
D. ( 0.259 times 207 dot{A} )
11
723Which of the following can occupy space and has mass?
A. Density
B. weight
c. Matter
D. A solid
E. volume
11
724Most of the alpha particles pass:
A. straight through the gold foil
B. unusual through the gold foil
C . rare through the gold foil
D. none of the above
11
725Isotopes have same
A. atomic mass number
B. atomic number
C. number of neutrons
D. moles
11
726Find the ratio of specific charges ( left(frac{boldsymbol{q}}{boldsymbol{m}}right) ) of an ( alpha- ) particle and a deuteron?11
727( N a^{+}, M g^{2+}, A l^{3+} ) and ( S i^{4+} ) are
isoelectronic ions. Their ionic size
follows the order:
A ( cdot N a^{+}<M g^{2+}<A l^{3+}M g^{2+}s i^{4+} )
C. ( N a^{+}A l^{3+}>S i^{4+} )
D. ( N a^{+}>M g^{2+}>A l^{3+}>S i^{4+} )
11
728Although ( C N^{-} ) ion and ( N_{2} ) molecule
are isoelectronic, yet ( N_{2} ) molecule is chemically inert because of:
A. presence of more number of electrons in bonding orbitals
B. a bond energy
c. absence of bond polarity
D. uneven electron distribution
11
729An ion ( M^{2+} ) contains 10 electrons and 12
neutrons. What is the atomic number
and mass number of element M?
A .10,24
B. 10,22
c. 12,24
D. 12, 22
11
730Which of the following element is represented by electronic configuration ( mathbf{1} boldsymbol{s}^{2} mathbf{2} boldsymbol{s}^{2} mathbf{2} boldsymbol{p}_{boldsymbol{x}}^{1} mathbf{2} boldsymbol{p}_{boldsymbol{y}}^{mathbf{1}} boldsymbol{2} boldsymbol{p}_{z}^{1} )
A. Nitrogen
B. Oxygen
c. Fluorine
D. sulphur
11
731Which of the following atoms and ions are iso electronic(i.e have the same
number of electrons) with a neon atom:
( mathbf{C}, mathbf{O}^{2-}, mathbf{N}^{-}, mathbf{F}^{+}, mathbf{N a}^{+}, mathbf{A} mathbf{l}^{mathbf{3}+} )
A ( cdot mathrm{N}^{-}, mathrm{Na}^{+}, mathrm{Al}^{3+} )
B. ( c, O^{2}-, N a^{+}, F^{+} )
( mathbf{c} cdot mathbf{0}^{2-}, mathbf{N a}^{+},left.mathbf{A}right|^{3} )
D. ( c, 0^{2}-, F^{+},left.Aright|^{3+} )
11
732Matter can be defined as something
that:
A. Occupies space
B. Has mass
c. Exists in three states
D. All of the above
11
733A quantity of aluminium has a mass of
54g. What is the mass of same number
of magnesium atoms?
A. ( 12.1 g )
в. ( 24.3 g )
c. ( 48.6 g )
D. ( 97.2 g )
11
734If two subshells have equal value of
( (n+1) ) and one of them has ( n=4, l=3, ) while
second subshell has dumbbellshape.
Then which of the bfollowing statement is/are correct?
This question has multiple correct options
A. Second subshell has value of ( n=6 )
B. One of the orbitals of second subshell has one nodal plane
c. second subshell is d-subshell.
D. First subshell is f-subshell
11
735What is the maximum number of
orbitals that can be identified with the
following quantum numbers?
( left[n=3 ; l=1 ; m_{l}=0right] )
( A )
B. 2
( c cdot 3 )
D.
11
736Which radioactive series do not show
the formation of radon atom as one of
the intermediate?
A. ( T h ) series
B. Np series
c. ( U ) series
D. ( A c ) series
11
737How many elements are possible for the
( 1^{s t} ) period of periodic table if azimuthal quantum number can have integral values from 0 to ( (n+1) .[n= ) shell number and other rules are remaining same to form period table?
A . 4
B. 6
( c cdot 2 )
( D cdot 8 )
11
738Uncertainty in the position of an electron ( left(text {mass}=mathbf{9 . 1} times mathbf{1 0}^{-mathbf{3 1}} mathbf{k g}right) )
moving with a velocity ( 300 m s^{-1} )
accurate upon ( 0.001 % ) will be:
( left[boldsymbol{h}=mathbf{6 . 6 3} times mathbf{1 0}^{-mathbf{3 4}} boldsymbol{J}-boldsymbol{s}right] )
A ( cdot 19.2 times 10^{-2} mathrm{m} )
в. ( 5.76 times 10^{-2} ) т
c. ( 1.92 times 10^{-2} mathrm{m} )
D. ( 3.84 times 10^{-2} mathrm{m} )
11
7395. Angular momentum (L) and radius (r) of a hydrogen atom
are related as
(a) Lr = constant (b) Lr2 = constant
(c) Lrt = constant (d) none of these
11
740A mixture is made from different
substances that are
A. not chemically joint
B. chemically joint
c. physically joint
D. not physically joint
11
741The velocity of the electron in 3rd orbit
of hydrogen atom in ( mathrm{cm} s^{-1} )
A ( cdot 4.88 times 10^{4} )
B . ( 2.44 times 10^{8} )
c. ( 7.29 times 10^{7} )
D. ( 2.44 times 10^{12} )
11
742According to postulated of Bohr’s atomic model, the electron has a
definite amount of energy and the electron does not lose or gain energy
while moving:
A. in the orbit
B. in the nucleus
c. in the atom
D. in the molecul
11
743Which one of the following represents the correct ratio of the energy, of electron in ground state of H atom to
that of the electron in the first excited
state of ( boldsymbol{L} boldsymbol{i}^{+} ? )
A .4: 9
B. 9: 4
( c cdot 1: 4 )
( D cdot 4: 1 )
11
744Ground state electronic configuration of nitrogen atom can be represented by :
This question has multiple correct options
( A )
( uparrow downarrow )
в. ( uparrow downarrow )
( c )
D. ( uparrow downarrow ) ( downarrow downarrow downarrow downarrow downarrow )
11
745Which of the following ion is not
isoelectronic with ( O^{-2} ) ?
A ( cdot N^{-3} )
В. ( N a^{+} )
( c cdot F^{-} )
D. ( T i^{+3} )
11
746(a) Calculate the radii of the first three
Bohr orbits for hydrogen. (Planck’s constant ( boldsymbol{h}=mathbf{6 . 6 2 6 2} times mathbf{1 0}^{-mathbf{3 4}} )
Js; mass of electron ( boldsymbol{m}=mathbf{9 . 1 0 9 1} times )
( 10^{-31} mathrm{kg} ; ) charge on electron ( e= )
( mathbf{1 . 6 0 2 1 0} times mathbf{1 0}^{-mathbf{1 9}} mathbf{C} ; ) permittivity of
vacuum ( epsilon_{0}=8.854185 times )
( left.10^{-12} C^{2} N^{-1} m^{-2} .right) )
(b) Use these radii to calculate the
velocity of an electron in each of these
three orbits.
11
747Which of the following is the standard for atomic mass?
A ( cdot frac{1}{1} H )
B . ( _{6}^{12} mathrm{C} )
( mathbf{c} cdot frac{i 4}{6} C )
D. ( _{8}^{6} C )
11
748Find Kinetic energy of an ( alpha ) -particle?
( left.boldsymbol{v}=mathbf{3} times mathbf{1 0}^{7}right) )
( mathbf{A} cdot 1.3 times 10^{-5} ) erg
В ( cdot 2.9 times 10^{-5} ) erg
c. ( 8.0 times 10^{18} ) erg
D. ( 8 times 10^{-18} ) erg
11
749On the basis of Rutherford’s model of an
atom, which subatomic particle is present it the nucleus of an atom?
11
750Carbon has six protons and six neutrons in its nucleus. What is the
atomic mass of carbon?
( A cdot 4 )
B. 12
( c cdot 8 )
D. 6
11
751Which of the following isoelectronic ions have lowest ionisation energy?
A . ( K^{+} )
в. ( C a^{2} )
c. ( C l^{-} )
( D cdot S^{2} )
11
752Select the incorrect option regarding following plot.
A. Minimum possible angular node will be zero
B. It is for ( n-1-1=0 )
c. wave function does not depend on angle ( theta ) and ( phi )
D. It gives probability of finding the electron at a point at distance r from the nucleus
11
753Which form of energy is a measure of
the electron stability when it is in bound state with nucleus?
A. Potential energy
B. Kinetic energy
c. vibrational energy
D. lonization energy
11
754What does the electronic configuration
( 1 s^{2}, 2 s^{2}, 2 p^{5}, 3 s^{1} ) indicate?
A. Ground state of fluorine
B. Excited state of fluorine
c. Excited state of neon
D. Excited state of the ( O_{2}^{-} ) ion
11
755The maximum number of electrons in a
shell with the principal quantum number ( =4 ) is :
A .2
B. 10
c. 16
D. 32
11
756A microscope using suitable photons is employed to locate an electron in an atom within a distance of 0.1 A. What is
the uncertainty involved in the measurement of its velocity? ( (h=6.626 )
( times 10^{-34} mathrm{Js}, ) mass of electron ( =9.1 )
( times 10^{-31} mathrm{kg} )
11
75778. An electron is in an excited state in a hydrogen like atom
It has a total energy of -3.4 eV. The kinetic enerov
electron is E and its de Broglie wavelength is 2
(a) E= 6.8 eV; 2 = 6.6 x 10-10 m
(b) E = 3.4 eV; 2 = 6.6 x 10-10 m
(C) E=3.4 eV; 2 = 6.6 x 10 m
(d) E = 6.8 eV; 2= 6.6 x 10 m
11
758have equal number of
neutrons.
A. Isobars
B. Isotones
c. Isotopes
D. Mass Number
11
759If 8.0 g of radioactive isotope has a half life of 10 hours, the half life of 2.0 g of the same substance is :
A. 2.5 hours
B. 5.0 hours
c. 10 hours
D. 40 hours
11
760Electromagnetic radiation having ( lambda= ) ( 310 dot{A} ) is subjected to a metal sheet having work function ( =12.8 mathrm{eV} . ) What will be the velocity of photo electrons having maximum kinetic energy?
A ( cdot 1.23 times 10^{6} m / s )
B . ( 2.28 times 10^{6} mathrm{m} / mathrm{s} )
c. ( 3.1 times 10^{6} m / s )
D. None of these
11
761Neutrons are discovered by:
A. J.J. Thomson
B. Goldstein
C. Crookes
11
762Assertion
Transition of electron between ( boldsymbol{p}_{boldsymbol{x}} ) and ( boldsymbol{p}_{boldsymbol{y}} )
would not lead to an spectral line.
Reason
( p ) -orbitals are degenerate orbitals.
Read the above assertion and reason
and choose the correct option regarding
¡t.
A. Both Assertion and Reason are correct and the Reason is the correct explanation of Assertion
B. Both Assertion and Reason are correct but the Reason is not the correct explanation of the Assertion
c. Assertion is correct but the Reason is incorrect
D. Assertion is incorrect and Reason is correrct
11
763What should be the kinetic energy of electron in the first orbit of hydrogen
atom?
11
764-bitat
7. The outermost electronic configuration of manganese (at. no. = 25) is
(a) 3 dº 4s² (6) 3 dº 45
(6) 3d 45°
(d) 3d 4s2
The energy needed to remova
1
11
765Which of the following is correct electronic configuration of argon?
A. 2,8
B. 2,8,8
c. 2,8,1
D. 8,2,8
11
766If ( r ) is radius of first orbit, the radius of
nth orbit of the ( mathrm{H} ) atom will be :
( A cdot m^{2} )
B. rn
( c cdot r / n )
( D cdot r^{2} n^{3} )
11
below:
( begin{array}{llllll}text { Elements } & boldsymbol{A} & boldsymbol{B} & boldsymbol{C} & boldsymbol{D} & boldsymbol{E} \ begin{array}{l}text { MASS } \ text { NO. }end{array} & 1 & 7 & 14 & 40 & 40 \ begin{array}{l}text { Atomic } \ text { No. }end{array} & 1 & 3 & 7 & 18 & 20end{array} )
11
768Which of the following quantum numbers are correct for the outermost
electron of sodium atom?
A. ( n=4, l=0, m=0, s=pm 1 / 2 )
В. ( n=3, l=0, m=0, s=-1 / 2 )
c. ( n=3, l=1, m=pm 1, s=+1 / 2 )
11
769The energy of a photon is given as
( 3.03 times 10^{-19} ) J/atom. The wavelength of
the photon is :
( A cdot 6.56 mathrm{nm} )
B. 65.6 nm
c. ( 0.656 mathrm{nm} )
D. 656 nm
11
770A free nucleus of mass 24 amu emits a
gamma photon (when initially at rest). The energy of the photon is 7 MeV. The recoil energy of the nucleus in KeV is:
(Assuming 1 amu ( =931 ) MeV )
A . 2.2
B. 1.
c. ( 3 . )
D. 22
11
771What do you mean by degenerate orbitals? Give examples.11
772The maximum probability of finding
electron in the ( d_{x y} ) orbital is:
A. along with ( x ) – axis
B. along the ( y ) -axis
c. at an angle of 45 from the ( x ) and ( y ) axis
D. at an angle of 90 from the ( x ) and ( y ) axis
11
7733. The wavelengths involved in the spectrum of deuterium
GD) are slightly different from that of hydrogen spectrum
because
(a) the attraction between the electron and the nucleus is
different in the two cases.
(b) the size of the two nuclei is different.
(c) the nuclear forces are different in the two cases.
(d) the masses of the two nuclei are different.
(AIEEE 2003)
11
774The wave function for an orbital is ( boldsymbol{H}- )
atom is given as:
( mathbf{Psi}= )
( left(frac{sqrt{2}}{81 sqrt{pi}}right)left(frac{1}{a_{0}}right)^{frac{2}{3}}left(6-frac{r}{a_{0}}right)left(frac{r}{a_{0}}right)^{-frac{r}{3 a}} )
The orbital is:
( A cdot 2 s )
в. ( 3 p )
( c cdot 2 p )
D. ( 3 d )
11
775Canal rays are:
A. alpha rays
B. light emitted when an electron falls into the nucleus
C. ionized gaseous atoms
D. light emitted when electron comes from a higher orbit to lower orbit
11
776State True or False.
( psi^{2} ) determines the probability of finding the electron in particular region of
space.
A. True
B. False
11
777What are the postulates of Bohr’s mode
of an atom?
11
778Einstein’s photo-electric equation
states that ( boldsymbol{E}_{boldsymbol{k}}=boldsymbol{h v}-boldsymbol{W} . ) In this
equation, ( boldsymbol{E}_{boldsymbol{k}} ) refers to:
A. kinetic energy of all ejected electrons
B. mean kinetic energy of emitted electrons
c. minimum kinetic energy of emitted electrons
D. maximum kinetic energy of emitted electrons
11
779Based on the equation, ( boldsymbol{E}=-mathbf{2 . 0} times )
( 10^{-18} frac{Z^{2}}{n^{2}} J, ) the wavelength of the light
that must be absorbed to excite
hydrogen electron from level ( n=1 ) to
level ( n=2 ) will be: ( (h=6.625 times ) ( left.mathbf{1 0}^{-mathbf{3 4}} boldsymbol{J} s, boldsymbol{C}=mathbf{3} times mathbf{1 0}^{mathbf{4}} boldsymbol{m} boldsymbol{s}^{-1}right) )
A . ( 1.2 times 10^{-7} mathrm{m} )
В . ( 1.325 times 10^{-7} mathrm{m} )
c. ( 5.300 times 10^{-10} mathrm{m} )
D. ( 1.325 times 10^{-10} m )
11
780Iron has ( _{-}-_{-}-_{-}- ) isotopes11
781Assertion
Orbit and orbital are synonymous.
Reason
A circular path around the nucleus in
which an electron moves is called orbit
or orbital.
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
11
782The wave function for ( 1 s ) orbital of the
hydrogen atom is given by
[
mathbf{Psi}_{1 s}=frac{boldsymbol{pi}}{sqrt{mathbf{2}}} boldsymbol{e}^{-boldsymbol{r} / boldsymbol{a}_{0}}
]
where ( a_{0}= ) Radius of first Bohr orbit ( r= ) Distance from the nucleus
(Probability of finding the electron varies with respect to it)
What will be the ratio of probabilities of finding the electrons at the nucleus to
first Bohr’s orbit ( a_{0} ? )
( A )
B ( cdot e^{2} )
( c cdot 1 / e^{2} )
D. zero
11
783( N_{2}, C O, C N^{-} ) and ( N O^{+} ) are
isoelectronic but the former is
chemically inert and later three are very reactive, why?
11
784Which is more hard, sponge or iron?11
785Which of the following quantities can only be a whole number?
B. Atomic number
c. Mass number
D. Equivalent weight
11
786What is the final velocity of an electron accelerating through a potential of 1600 ( V, ) if its initial velocity is zero?
A ( .2 .37 times 10^{9} mathrm{ms}^{-1} )
В. ( 4.74 times 10^{7} mathrm{ms}^{-1} )
c. ( 2.37 times 10^{7} m s^{-1} )
D. None of these
11
787Calculate the momentum of a particle which has a de Broglie wavelength of
( 2.5 times 10^{-10} m )
( left(h=6.6 times 10^{-34} k g m^{2} s^{-1}right) )
11
788Watch column A mame or the
Scientists) with column B (their
contributions towards the
understanding of the atomic structure).
Column A Column ( mathbf{B} )
A. Ernest Rutherford
1. Indivisibility of atoms
B. J.J Thompson
2. Stationary orbits
C. Dalton
3. Concept of nucleus
D. Neils Bohr
4. Discovery of electrons
5. Atomic number
F. E Goldstein
6. Neutron
G. Moseley ( quad ) 7. Canal rays
( mathbf{A} cdot A rightarrow 3, B rightarrow 4, C rightarrow 1, D rightarrow 2, E rightarrow 6, F rightarrow 7, G rightarrow 5 )
( mathbf{B} cdot A rightarrow 3, B rightarrow 4, C rightarrow 6, D rightarrow 2, E rightarrow 1, F rightarrow 5, G rightarrow 5 )
( mathbf{C} cdot A rightarrow 3, B rightarrow 4, C rightarrow 1, D rightarrow 2, E rightarrow 6, F rightarrow 5, G rightarrow 5 )
( mathbf{D} cdot A rightarrow 3, B rightarrow 4, C rightarrow 1, D rightarrow 2, E rightarrow 5, F rightarrow 7, G rightarrow 6 )
11
789Define isobars and isotopes.11
790What will be the ratio between the
radius of ( 3^{r} d ) shell of ( L i^{+2} & ) radius of
( 3^{r d} ) shell of the hydrogen atom?
11
791If the uncertainty in velocities of two
particles ( A ) and ( B ) with ( operatorname{mass} 1.0 x ) ( 10^{-27} k g ) and ( 1.0 times 10^{-31} k g )
respectively is same, the ratio of uncertainty in the positions of ( A ) and ( B ) is :
A . 1000:
B. 10,000:
c. 1: 1000
D. 1:10,000
11
792What are isotopes?
A. These are the forms of the same element having the same atomic number but different atomic masses due
to different nuclear structure.
B. These are the forms of the same element having the different atomic number but different atomic masses due to different nuclear structure.
C. These are the forms of the same element having the same atomic number but same atomic masses due to different nuclear structure.
D. none of these
11
793Which rule explains the electronic configuration of chromium is ( [mathrm{Ar}] ) ( 3 d^{5} 4 s^{1} ) instead of ( [A r] 3 d^{4} 4 s^{2} ? )
A. Pauli’s exclusion principle
B. Aufbau Principle
c. Hund’s rule
D. Heisenberg principle
11
794Goldstein’s work with anode rays of ( boldsymbol{H}^{+} ) was apparently the first observation of
the :
A. protons
B. electrons
c. neutrons
D. atoms
11
795An iron ball has a mass of 35 gms and a speed of ( 50 mathrm{m} / mathrm{s} ). If the speed can be measured with in accuracy of ( 2 % ) then the uncertainty in the position is :
A. ( 1.507 times 10^{-34} m )
В. ( 1.507 times 10^{-31} m )
c. ( 1.507 times 10^{-33} m )
D. ( 1.507 times 10^{-12} m )
11
796Which of the following orbitals has the lowest energy?
A . ( 4 d )
B. ( 4 f )
c. ( 5 s )
D. ( 5 p )
11
797What is the wavelength of light emitted when the electron in hydrogen atom undergoes transition from the energy
level with ( n=4 ) to energy level ( n=2 ? )
( left(operatorname{given} R_{n}=109678 c m^{-1}right) )
A. 786 nm
B. 486 nm
c. ( 586 mathrm{nm} )
D. 986 nm
11
798Which of the following spectra was not explained by Bohr’s Atomic model? This question has multiple correct options
A. Spectra of single electron system
B. Hydrogen spectra
c. spectra other than Hydrogen like atoms
D. spectra of helium atom
11
799If the position of the electron is measured within an accuracy of ( pm ) ( 0.002 mathrm{nm}, ) calculate the uncertainty in the momentum of the electron. Suppose the momentum of the electron is ( frac{h}{4 pi m} times 0.05 n m, ) is there any problem in defining this value?11
800If ( R_{H} ) is the Rydberg constant, then the energy of an electron in the ground
state of Hydrogen atom is:
A ( cdot frac{-R_{H}}{c h} )
в. ( frac{-1}{R_{H} c h} )
c. ( frac{-h c}{R_{H}} )
D. ( -R_{H} h c )
11
801The atomic number is identical to the
amount of ( _{—}-_{–} ) in the atom
nucleus.
A. Protons
B. Neutrons
c. Both a and
D. None of above
11
802Aufbau principle fails to explain the configuration of element with atomic
number:
( A cdot 18 )
B . 21
( c cdot 24 )
D. 27
11
803to determine the exact position and exact
Q.50 Assertion (A) It is impossible to determine the exact position
momentum of an electron simultaneously.
Reason (R) The path of an electron in an atom is clearly defined.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but is not the correct explanation of A
(c) A is true and R is false
(d) Both A and Rare false
11
804How many nodes are present in ( 3-mathrm{p} ) orbitals? Represent diagrammatically.11
805Calculate the wavelength and energy of radiation emitted for the electronic
transition from infinite to stationary
state of hydrogen atom. (Given, ( boldsymbol{R}= ) ( mathbf{1} . mathbf{0} mathbf{9 6 7} mathbf{8} times mathbf{1 0}^{mathbf{7}} mathbf{m}^{-mathbf{1}}, mathbf{h}=mathbf{6 . 6 2 5 6} times )
( 10^{-34} J-s ) and ( c=2.9979 times 10^{8} m s^{-1} )
)
11
806Which of the following is one of the postulates of Rutherford’s theory?
A. Electrons continuously lose energy
B. Electrons move in a spiral path around the nucleus
c. Electrons revolve in a specific path around the nucleus
D. Electrons revolve in a stationary orbit
11
807The approximate radius of polonium nucleus of mass number 210 is:
( mathbf{A} cdot 8 times 10^{-6} m )
B. ( 8 times 10^{-5} m )
( mathbf{c} cdot 4 times 10^{-6} m )
D. none of these
11
808Atoms of two elements ( P ) and ( Q ) have 5
electrons in ( 2^{n d} ) shell and ( 3^{r d} ) shell
respectively. What could be the geometric representations of ( boldsymbol{P} ) and ( boldsymbol{Q} ) ?
What will be the atomic numbers of
these elements?
11
80910. Hydrogen atom is excited from ground state to another
state with principal quantum number equal to 4. Then the
number of spectral lines in the emission spectra will be
(a) 2
(c) 5
(d) 6
(AIEEE 2012)
(b) 3
11.
com
11
810How many spherical nodes are present in ( 4 s ) orbital in a hydrogen atom?
A. 0
B. 2
( c cdot 3 )
( D )
11
8112p orbitals have:
A ( . n=1, l=2 )
B. ( n=1, l=0 )
c. ( n=2, l=1 )
D. ( n=2, l=0 )
11
812Consider a hypothetical atom where
( boldsymbol{p}_{boldsymbol{x}}, boldsymbol{p}_{boldsymbol{y}}, boldsymbol{p}_{boldsymbol{z}}, boldsymbol{d}_{boldsymbol{x} boldsymbol{y}}, boldsymbol{d}_{boldsymbol{x} z}, boldsymbol{d}_{boldsymbol{y} boldsymbol{z}} boldsymbol{a} boldsymbol{n} boldsymbol{d} boldsymbol{d} boldsymbol{x}^{2}-boldsymbol{y}^{2} )
orbital are present for principal quantum number ( n=3 ) Find the number of other orbitals whose
lobes are fully present in the nodal
plane of ( boldsymbol{p}_{boldsymbol{x}} ) orbital:
( A cdot 2 )
B. 3
( c cdot 4 )
D. 5
11
813State True or False.
Gamma rays are electromagnetic
radiations of wavelengths of ( 10^{-6} mathrm{cm} ) to
( 10^{-5} mathrm{cm} )
A. True
B. False
11
814The light velocity of revolving electrons is conquered by ……….. force of attraction of nucleus on an electron in
Rutherford’s model.
A. electrostatic
B. gravitational
c. magnetic
D. van der waals
11
815The manganese ( (Z=25) ) has the outer
configuration:
( A )
45
( uparrow downarrow )
B.
45
( uparrow downarrow ) begin{tabular}{|c|c|c|c|c|}
hline multicolumn{2}{|c|} {( 3 d )} & multicolumn{2}{|c|} {} \
hline( uparrow ) & ( uparrow ) & ( uparrow ) & ( uparrow ) & ( uparrow ) \
hline
end{tabular}
( c )
begin{tabular}{c}
( 4 s ) \
hline( uparrow downarrow )
end{tabular} begin{tabular}{|c|c|c|c|}
hline multicolumn{2}{|c|} {( uparrow d )} & multicolumn{2}{c|} {} \
hline( uparrow downarrow mid uparrow downarrow ) & ( uparrow ) & & \
hline
end{tabular}
( D )
45
11
816Which of the following has the maximum penetrating power?
( A cdot alpha- ) Jarticle
B. Proton
c. ( gamma ) – particle
D. Positron
11
817What are the main postulates of Bohr’s theory of an atom?11
818In which of the following energy of ( 2 s ) orbital is minimum.
A . ( L i )
в. ( N a )
( c . K )
D. ( H )
11
819The wavelength range of the visible spectrum extends from violet ( (400 n m) ) to red ( (750 n m) . ) Express these wavelengths in frequencies ( (boldsymbol{H} boldsymbol{z}) ) ( left(1 n m=10^{-9} mright) )11
820The atoms in a molecule do not remain
stationary. They vibrate around their mean position, by stretching or bending out of plane. We gain useful knowledge about these vibrations and the energy
they carry by studying:
A. ( X ) -ray spectra
B. ultraviolet spectra
c. infrared spectra
D. visible spectra
11
821How many elements will be present in
( 5^{t h} ) period of the periodic table? Justify
using quantum numbers.
11
822Calculate the mass number of atoms
( X, Y ) and ( Z ? )
A . 5,11,18
B. 10,18,31
c. 11,18,3
D. 11,19,30
11
823What transition in the hydrogen spectrum would have the same
wavelength as the Balmer transition, ( n= )
4 to ( n=2 ) of ( H e^{+} ) spectrum?
11
824Identify the correct ground state
electrons configuration for ( boldsymbol{C r} ) :
( mathbf{A} cdot[A r] 3 s^{2} 3 d^{4} )
B . ( [A r] 3 s^{2} 3 d^{5} )
c. ( [A r] 4 s^{2} 3 d^{5} )
D ( cdot[A r] 4 s^{2} 3 d^{4} )
E ( cdot[A r] 4 s^{1} 3 d^{5} )
11
825What does the negative electronic energy (negative sign for all values of energy) for hydrogen atom means?
A. The energy of an electron in the atom is lower than the energy of a free electron at rest which is taken as zero
B. When the electron is free from the influence of nucleus it has a negative value which becomes more negative
c. When the electron is attracted by the nucleus the energy is absorbed which means a negative value
D. Energy is released by hydrogen atom in ground state
11
826Write electronic configurations of the
( boldsymbol{H} e )
11
827The quantum numbers of most energetic electron in Ar atom when it is in first excited state is:
A ( cdot_{2,1,0, pm} frac{1}{2} )
в. ( _{4,1,1, pm} frac{1}{2} )
c. ( _{4,0,0, pm} frac{1}{2} )
D. ( _{4,1,0, pm} frac{1}{2} )
11
828If moving with equal speeds, the longest wavelength of the following matter waves is that for a (an):
A. electron
B. ( alpha ) -particle
c. proton
D. neutron
11
829The number of spherical nodes in ( 3 p ) orbital is/are:11
830The charge on ( alpha ) -particle is the charge on proton.
A . twice
B. thrice
c. half
D. same as
11
831An atom has electronic configuration of
2,8,18,7
What is the atomic number the of
atom?
A. 7
B. 35
c. 70
D. 17
11
832Give the main drawback of Rutherford’s
model.
11
833The number of orbitals in ( n=3 ) are:
( mathbf{A} cdot mathbf{1} )
B. 4
( c cdot 9 )
D. 16
11
834Which series have highest energy in hydrogen spectrum?
A. Balmer
c. Pfund
D. Lyman
11
835The speed of the electron in the 1 st orbit of the hydrogen atom in the ground state is: ( (c ) is the velocity of light)
A ( cdot frac{c}{1.37} )
в. ( frac{c}{1370} )
c. ( frac{c}{13.7} )
D. ( frac{c}{137} )
11
836( X ) -rays:
A. are deflected in a magnetic field.
B. are deflected in an electric field.
C. remain undeflected by both electric and magnetic fields.
D. are deflected in both electric and magnetic fields.
11
837Which of the following species has more number of protons than the number of electrons?
( A cdot F^{-} )
в. ( N a^{+} )
( c cdot O^{2} )
D. Ne
11
83836. A sample of hydrogen is bombarded by electrons.
Through what potential difference should the electrons be
accelerated so that third line of Lyman series be emitted?
(a) 2.55 V
(b) 10.2 V
(c) 12.09 V
(d) 12.75 V
11
839For emission line of atomic hydrogen
from ( n_{i}=8 ) to ( n_{f} ) – the plot of wave number ( (bar{v}) ) against ( left(frac{1}{n^{2}}right) ) will be: (The Rydberg constnt, ( R_{H} ) is in wave number
unit).
A . linear with slope ( -R_{H} )
B. linear with intercept – ( R_{H} )
c. non linear
D. linear with slope ( R_{H} )
11
840Define the atomic mass unit.
A. Mass unit equal to exactly one-twelfth the mass of a carbon-12 atom
B. Mass unit equal to exactly the mass of a carbon-12 atom
C. Mass unit equal to exactly one-twelfth the mass of a hydrogen atom
D. All of the above
11
841Complete the table given below
( begin{array}{ll}text { No. of } & text { No. of } \ text { Protons } & text { Electr }end{array} ) No. of Electrons Neutror
( _{13}^{35} C l )
[
_{17}^{37} C l
]
11
842Atomic radius is of the order of ( 10^{-8} mathrm{cm} )
and nuclear radius is of the order of
( 10^{-13} mathrm{cm} . ) The fraction of atom occupied
by nucleus is:
A ( cdot 10^{-5} )
B . ( 10^{5} )
( mathbf{c} cdot 10^{-15} )
D. none of these
11
843Which of the following metals require radiation of highest frequency to cause emmission of electrons?
A. ( N a )
в. ( M g )
( c . k )
D. ( C a )
11
844How many unpaired electrons are there
in ( mathrm{Ni}^{2+} ) ?
( A cdot O )
B. 2
( c cdot 4 )
D. 8
11
845An excited hydrogen atom emits a photon of wavelength ( lambda ) in returning to
the ground state. If ( R ) is the Rydberg
constant, then the quantum number ( n )
of the excited state will be:
( A cdot sqrt{lambda R} )
B. ( sqrt{lambda R-1} )
c. ( sqrt{frac{lambda R}{lambda R-1}} )
D. ( sqrt{lambda R(lambda R-1)} )
11
846Out of given atoms which atoms has highest energy of 2 s-subshell ?
A .
B. Li
c. Na
D. All have same
11
847Which of the following graphs represents the correct variations for De
Broglie wavelengths of electrons:
( A )
B.
( c )
D. none
11
848Adding an alpha particle to nucleus of sodium atom, product will be
A . ( N a^{text {t }} )
в. ( M g^{2+} )
c. ( A l^{2} )
D. ( A l )
11
849A golf ball has mass of ( 30 g ) and a speed of ( 50 mathrm{m} / mathrm{s} ). If the speed can be
measured within accuracy of ( 1 % ) then uncertainty in the position is:
A. ( 2.4 times 10^{-32} mathrm{m} )
В. ( 3.5 times 10^{-33} mathrm{m} )
c. ( 3.5 times 10^{-34} mathrm{m} )
D . 2.4 ( times 10^{-33} mathrm{m} )
11
85062. Transitions between three energy levels in a particular
atom give rise to three spectral lines of wavelengths, in
increasing magnitudes, 21, 22, and ls. Which one of the
following equations correctly relates 21, 22, and is?
(a) a = – dz (b) 2 = 2z –
1
(d)
1
1
(c) +-11
2 ata
21
22
23
21
22
22
11
851Q66. Indicate the number of unpaired electrons in :
(a) P (b) Si (c) Cr (d) Fe and (e) Kr.
11
852Emission of ( beta ) -particles by an atom of an element results in the formation of
A. isobar
B. isomer
( c . ) isotope
D. isotone
11
853Q3. What were the weaknesses or limitations of Bohr’s model of atoms? Briefly describe the quantum
mechanical model of atom.
11
854Assertion
To overcome electrostatic force of
attraction between electrons and
nucleus, they revolve around the
nucleus.
Reason
Mass of the atom is almost due to its
nucleus.
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.
11
855Q10. What is the difference between ground state and excited state?
L. TALL. the plante
11
85658. When the hydrogen atom emits a photon in going from
n = 5 to n = 1 state, its recoil speed is nearly
(a) 104 m s-1
(b) 2 x 10-2 ms
(c) 4 m s-1
(d) 8 x 102 ms-1
11
857Identify the correct statement(s) from
the following. This question has multiple correct options
A. The ion having a positive charge on it is known as electro – positive ion.
B. The ion having a negative charge on it is known as electro – negative ion.
C. Simple ion is an ion which contains one or more atoms of the same element.
D. Compound ion is an ion which contains two or more atoms of different elements forming a single unit.
11
858When electrons in sample of H-atom make transitions from 5th excited state
to ground state, then the maximum number of spectral lines which belong to visible region is:
A . 10
B. 4
c. 15
D. 5
11
85929. A hydrogen-like atom emits radiations of frequency
2.7 x 1015 Hz when it makes a transition from n = 2 to
n = 1. The frequency emitted in a transition from n = 3
to n= 1 will be
(a) 1.8 x 10 Hz (b) 3.2 x 10 Hz
(c) 4.7 x 10 Hz (d) 6.9 x 10 Hz
11
860The most probable radius (in pm) for
finding the electron in ( boldsymbol{H} boldsymbol{e}^{+} ) is:
A . ( 0 . )
в. 52.9
c. 26.45
D. 105.8
11
861Which is correct relationship?
( mathbf{A} cdot E_{1} ) of ( H=frac{1}{2} E_{2} ) of ( mathrm{H} e^{+}=frac{1}{3} E_{3} ) of ( L i^{+2}= )
( frac{1}{4} E_{4} ) of ( B e^{+3} )
B ( cdot E_{1}(H)=E_{2}left(H e^{+}right)=E_{3}left(L i^{+2}right)=E_{4}left(B e^{+3}right) )
C ( cdot E_{1}(H)=2 E_{2}left(H e^{+}right)=3 E_{3}left(L i^{+2}right)=4 E_{4}left(B e^{+3}right) )
D. No relation
11
8629. The maximum number of electrons in a sub-shell is given by the equation
(a) n²
(6) 2n?
(c) 21-1
(d) 21 +1
TE
11
863Which one of the following explains light both as a stream of particles and
as wave motion?
A . Diffraction
в. ( lambda=h / p )
c. Interference
D. Photoelectric effect
11
864State True or False.
The three quantum numbers were clearly explained in terms of Schrodinger wave equation.
A. True
B. False
11
865If the speed of electron in the Bohr’s first
orbit of hydrogen is ( x, ) the speed in the third orbit is:
A. ( x / 9 )
B. ( x / 3 )
( c .3 x )
D. ( 9 x )
11
866Which of the following does not contain material particles?
A. ( alpha ) -rays
B. ( beta ) -rays
c. ( gamma ) -rays
D. Anode rays
11
86754. A beam of electron accelerated by a large potential
difference V is made to strike a metal target to produce
X-rays. For which of the following values of V, will the
resulting X-rays have the lowest minimum wavelength?
(a) 10 kV
(b) 20 kV
(c) 30 kV
(d) 40 kV
11
868Which among the following statements is/are correct?
This question has multiple correct options
A. ( Psi^{2} ) represents the atomic orbitals
B. The number of peaks in radial distribution is ( (n-1) )
C . Radial probability density ( rho_{n l}(r)=4 pi r^{2} R_{n l}^{2}(r) )
D. A node is a point in space where the wave function has zero amplitude
11
869Which element has electrons in ( f )
orbitals?
( A cdot A r )
B.
( c cdot s )
D. Ti
E.
11
870Calculate the mass of a photon of
sodium light having wavelength ( 5894 A )
and velocity ( 3 times 10^{8} mathrm{m} / mathrm{s} )
( left(h=6.6 times 10^{-34} K g m^{2} s^{-1}right) )
11
871The wave length of second line in the Balmer series of hydrogen spectrum is equal to: (R=Rydberg constant)
( mathbf{A} cdot 36 / 5 R )
в. ( 5 R / 36 )
c. ( 3 R / 16 )
D. ( 16 / 3 R )
11
872The atomic number of an element ( X ) is
13.What will be the number of electrons
in its ion ( X^{34} )
11
873An ( alpha ) -particle is identical with:
A. proton
B. neutron
c. helium nucleus
D. electron
11
874( ^{210} 84^{circ} mathrm{o} longrightarrow_{82}^{206} mathrm{Pb}+_{2}^{4} mathrm{He} )
In this reaction, predict the position of group of ( P o ) in periodic table when lead
is in the ( I V A ) group:
A . IIA
в. ( I V B )
c. ( V I A )
D. ( V I B )
11
875Which of the following is the main cause of late discovery of neutron?
A. Neutron is highly unstable particle
B. Neutron in nucleus moves very fast
c. Neutron is charge-less particle
D. All of the above
11
876Assertion
The mass number of an atom is the
sum of number of protons and neutrons it contains.
Reason
The mass number of an atom can never
be smaller than the atomic number.
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
11
877Which of the following are isoelectronic species?
(i) ( boldsymbol{N} boldsymbol{H}_{mathbf{3}} )
(ii) ( boldsymbol{C} boldsymbol{H}_{3}^{+} )
(iii) ( boldsymbol{N} boldsymbol{H}_{mathbf{2}}^{-} )
(iv) ( boldsymbol{N} boldsymbol{H}_{mathbf{4}}^{+} )
Choose the correct answer from the
codes given below:
A ( cdot(i),(i i),(i i i) )
B. (i),(iii), (iv)
C . ( (i),(i i),(i v) )
D. ( (i i),(i i i) )
E. None of these
11
878X-rays emitted from a copper target and
a molybdenum target are found to
contain a line of wavelength ( 22.85 mathrm{nm} ) attribute to the ( K_{alpha} ) lines of an impure
element. The ( K_{alpha} ) lines of copper ( (mathrm{Z}=29 )
and molybdenum ( (mathrm{Z}=42) ) have a
wavelength 15.42 nm and 7.12 nm respectively. Using Moseley’s law, ( v^{1 / 2}=a(Z-b), ) calculate the atomic
number of the impure element:
A .24
B . 28
c. 30
D. 32
11
879State True or False.
The properties of elements are periodic function of their atomic number
A. True
B. False
11
880Protons and neutrons are also called
A . nucleons
B. isotope
c. isobars
D. elements
11
881Rutherford’s scattering formula fails for very small scattering angles because:
This question has multiple correct options
A. the gold foil is very thin
B. the kinetic energy of ( alpha ) -particles is very high
C. the full nuclear charge of the target atom is partially screened by its electron
D. there is strong repulsive force between the ( alpha ) -particles and nucleus of the target
11
88242. When a metal is heated in a
flame, the electrons absorb en-
state. On coming back to the low-
er energy siate, they emit light,
which we can observe in
(1) Raman spectra
(2) Absorption spectra
(3) Emission spectra
(4) Fluorescence
11
883The wavelength of light wave of wave
number ( 4000 mathrm{cm}^{-1} ) is:
11
88422. In a hydrogen atom, the transition takes place
place from
n=3 to n = 2. If Rydberg’s constant is 1.09 x 10
the wavelength of the line emitted is
(a) 6606 X
(b) 4861 A
(c) 4340 Å
(d) 4101 A
11
885Which of the following statements on the atomic wave function ( Psi ) is not
correct?
A. ( Psi ) may be a real valued wave function
B. ( Psi ) may be in some cases be a complex function
c. ( Psi ) has a mathematical significance only
D. ( Psi ) is proportional to the probability of finding an electron
11
886An orbital made of four lobes can have
the following quantum numbers:
A ( cdot n=2,1=2, m=0 )
B. ( n=3,1=1, m=-2 )
( c cdot n=3,1=2, m=0 )
D. ( n=3,1=3, m=-3 )
11
887Radioactive disintegration differs from a chemical change in being:
A. an exothermic change
B. a spontaneous process
c. a nuclear process
D. a unimolecular first-order reaction
11
888An isotope of helium is represented by the symbol ( _{2}^{3} H e . ) How many protons, neutrons and electrons are there in an
atom of the isotope?
A. 1 proton, 2 neutrons, 1 electron
B. 1 proton, 3 neutrons, 2 electrons
C. 2 protons, 1 neutron, 2 electrons
D. 2 protons, 3 neutrons, 2 electrons
11
889Which of the following orbitals is closer to nucleus?
( A cdot 5 f )
B. 6d
( c cdot 7 s )
D. ( 7 p )
11
890In hydrogen atom, energy of first excited state is ( -3.4 e V . ) Then find out the ( K E )
of the same orbit of hydrogen atom.
A. +3.4 eV
B. ( +6.8 e V )
c. ( -13.6 e V )
D. ( +13.6 e V )
11
891Q22. What is difference between the notations 1 and L?
Y
11
892An atom does not carry any electric charge because it
A. has an equal number of charged and non charged particles
B. has neutrons in their nuclei
C. has an equal number of electrons and protons, hence positive and negative charge gets neutralized.
D. has an equal number of neutrons and protons
11
893What was the requirement for introducing atomic orbital concept?11
894Which of the following statements is
not true?
A. The ratio of the mean speed of the RMS speed is independent of the temperature
B. The square of the mean speed of the molecules is equal to the mean square speed at a certain temperature
C. Mean kinetic energy of the gas-molecules at any given temperature is independent of the mean speed
D. The difference between RMS speed and mean speed at any temperature for different diminishes as larger and yet larger molar masses are considered
11
895Which one of the following sets of ions represent the collection of isoelectronic
species?
A ( cdot K^{+}, C a^{2+}, S c^{3+}, C l^{-} )
B. ( N a^{+}, M g^{2+}, A l^{3+}, C l^{-} )
C ( cdot K^{+}, C l^{-}, M g^{2+}, S c^{3+} )
D. ( N a^{+}, C a^{2+}, S c^{3+}, F^{-} )
11
896As per Bohr’s model, an electron in an uni-electronic species revolves around
the nucleus in circular orbits. What is
the radius of the 3 rd orbit of ( boldsymbol{H} boldsymbol{e}^{+} ) ion?
A ( .2 .38 AA )
В. ( 1.19 dot{A} )
c. ( 0.7 dot{h} )
D. ( 4.76 AA )
11
897We have four substances ( mathrm{P}, mathrm{Q}, mathrm{R}, mathrm{S} )
Substance ( P ) is dark coloured violet
solid having diatomic molecules.
Solution of ( P ) in alcohol is an Antiseptic ‘T’ Substance ‘Q’is a white solid usually
recovered from sea on a large scale.
Substance ‘R’ is also a white solid
insoluble in water and used in the form
of small balls for safe storage of woolen
clothes. Substance ‘S’ is a white solid
too used in dry cell. P,Q,R,S,T, may be (choose correct option)
A. P-lodine, Q-Napthalene,R- ( R-N H_{4} C I ) S-Nacl, T-lodin
tincture
B. P-NaCI,Q-Napthalene, ( R-N H_{4} C I )
S-lodine, T-lodine tincture
C. P-lodine tincture, Q- ( R-N H_{4} C I R ) – lodine, S-
Napthalene, T-NaCl
D. P-lodine, Q-Nacl, R- Napthalene
S- ( R-N H_{4} C I, ) T-lodine tincture
11
898The probability ( (P) ) of survival of ( a ) radioactive nucleus in its mean life is:
( A cdot frac{1}{e} )
B. ( frac{1}{lambda} )
c. ( frac{0.633}{lambda} )
D.
11
899The orbital with zero orbital angular
momentum is :
A . s
B.
( c cdot d )
( D )
11
900Q.5 Which of the following statements about the electron is incorrect?
(a) It is a negatively charged particle
(b) The mass of electron is equal to the mass of neutron
(c) It is a basic constituent of all atoms
(d) It is a constituent of cathode rays
11
901If Aufbau rule is not followed in filling of sub orbitals, then block of the element
will change in:
A. K(19) (i) (19) (19) 19
B. ( operatorname{Sc}(21) )
( c cdot v(23) )
( D cdot N i(28) )
11
902Principal quantum number defined
for
A. shell
B. subshell
c. orbital
D. spin
11
903The space between proton and electron in hydrogen atom is :
A. absolutely empty
C. full of air
D. full of ether
11
904Rutherford’s scattering experiment led
to the conclusion that:
A. nucleus is very small in size
B. nucleus is very heavy and carries positive charge
C. most of the space in the atom is empty
D. all of these
11
905The first emission line in the atomic
spectrum of hydrogen in the Balmer series appears at:
A ( cdot frac{9 R}{400} c m^{-1} )
B. ( frac{7 R}{144} mathrm{cm}^{-1} )
( ^{mathrm{C}} cdot frac{3 R}{4} c m^{-1} )
D. ( frac{5 R}{36} c m^{-1} )
11
906The angular momentum of an electron
in the ( 2^{n d} ) excited state ofa Helium ion
( left(boldsymbol{H} boldsymbol{e}^{+}right) ) is:
A ( cdot frac{h}{2 pi} )
в. ( frac{2 h}{2 pi} )
( c cdot frac{3 h}{2 pi} )
D. ( frac{4 h}{2 pi} )
11
907Wave functions of electrons in atom and
molecules are called:
A. orbitals
B. azimuthal quantum number
c. orbits
D. degenerate orbitals
11
908Cathode rays have:
A. mass only
B. charge only
C. both mass and charge
D. neither mass nor charge
11
90966. An electron revolving in an orbit of radius 0.5 A in a
hydrogen atom executes 10° revolutions per second. The
magnetic moment of electron due to its orbital motion will
be
(a) 1.256 x 10-23 A m² (b) 653 x 10-26 A m?
(c) 10-3 A m
(d) 256 x 10-26 A m
11
910The spaces between molecules is least
in :
A. Solid
B. Liquid
c. Gases
D. Vapour
11
911The atom ( A, B, C ) have the configuration ( A rightarrow[Z(90)+n(146)], B rightarrow[Z(92)+ )
( mathrm{n}(146)], mathrm{C} rightarrow[mathrm{Z}(90)+mathrm{n}(148)] ) So that
(a) ( A ) and ( C- ) Isotones
(b) A and C –
Isotopes
(c) ( A ) and ( B ) – Isobars
(d) ( B ) and ( c- )
Isobars
(e) ( mathrm{B} ) and ( mathrm{C} ) – Isotones
The wrong statements are:
A. a, bonly
B. c, d, e only
c. a ( , c, d ) only
D. a, d, e only
11
912-0-
1515 0
04. What is the most important application of de Broglie concept:
measurement of
11
913Write electronic configurations of the Sodium.11
914The orbital having minimum ( l ) value is:
A. spherical in shape
B. dumbell in shape
c. double dumbell in shape
D. tetrahedral in shape
11
915Bohr’s atomic model is based on the
following postulates:
This question has multiple correct options
A. an atom consists of nucleus.
B. an electron can rotate only in certain energy levels.
C . an electron remains moving with continuous loss of energy.
D. none of the above.
11
916Among the following which one contains valence electrons in the ground state of
the magnesium ( M g ) atom?
A . ( 1 s )
B . ( 2 s )
c. ( 3 s )
D. ( 3 p )
E . ( 3 d )
11
917State True or False.
The electron distribution is spherically symmetrical for ( l=2 )
A. True
B. False
11
918Responsible for most helium found on Earth:
A. Gamma decay
B. Nuclear fusion
c. Alpha decay
D. Positron emission
E. Nuclear fission
11
919The electron density in the xy-plane in
( 3 d_{x^{2}-y^{2}} ) orbital is zero. If true enter 1 else enter 0
11
920Define matter.11
921Assertion
The configuration of ( B ) -atom cannot be
( 1 s^{2} 2 s^{2} )
Reason
Hund’s rule demands that the
configuration should display maximum multiplicity.
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
11
922Which of the following spectrochemical series is true?
A ( cdot S C N^{-}<N H_{3}<F^{-}<e n<C O )
B . ( S C N^{-}<F^{-}<N H_{3}<e n<C O )
c. ( S C N^{-}<F^{-}<e n^{-}<N H_{3}<C O )
D. ( S C N^{-}<F^{-}<e n^{-}<C O^{-}<N H_{3} )
11
923The quantum number ‘m’ of a free
gaseous atom is associated with:
A. the effective volume of the orbital
B. the shape of the orbital
C. the spatial orientation of the orbital
D. the energy of the orbital in the absence of a magnetic field
11
924Assertion: Angular momentum of an
electron in any orbit is given by angular momentum ( =frac{n . h}{2 pi}, ) where ( n ) is the
principal quantum number. Reason: The principal quantum number, ( n, ) can have any integral value.
A. If both assertion and reason are true and the reason is
a correct explanation of the assertion.
B. If both assertion and reason are true but reason is not
a correct explanation of the assertion
C. If the assertion is true but reason is false
D. If both the assertion and reason are false
E. If the assertion is false but the reason is true
11
deflection in a magnetic field is:
A. ( alpha ) -particles
B. ( beta ) -particles
c. ( x ) -rays
11
926The maximum no. of electrons
having parallel spin in the configuration ( 4 s^{2} 4 p^{5} ) are:
( A cdot 7 )
B. 4
( c .3 )
D. 5
11
927According to Bohr’s model, the angular
momentum of an electron in 4th orbit
is:
( mathbf{A} cdot h / 3 )
B. ( h / 2 )
c. ( 2 h / pi )
D. none of these
11
928Energy of the electron in Bohr’s orbit is equal to?
A. potential energy only
B. Kinetic energy only
c. Sum of potential and kinetic energy
D. difference of kinetic and potential energy
11
929( 4 s^{2} ) is the configuration of the outermost orbit of an element. Its
atomic number would be:
A . 29
B. 24
( c . ) 30
D. 19
11
930Electron was discovery by J.J. Thomson
A. True
B. False
11
931The amount of energy required to remove an electron from ground sate of
( H e^{+} ) ion is:
A. -54.4 ev
B . -13.6 ev
c. -24.4 ev
D. -34 ev
11
932A transition metal ‘X’ has a
configuration ( [mathrm{Ar}] 3 d^{4} ) in its +3
oxidation state, its atomic number is:
A . 25
B . 26
( c cdot 22 )
D. 19
11
933Q. 4 Which of the following statement is not correct about the characteristic
of cathode rays?
(a) They start from the cathode and move towards the anode
(b) They travel in straight line in the absence of an external electrical or magnet
field
(c) Characteristics of cathode rays do not depend upon the material of electrodes is
cathode ray tube
(d) Characteristics of cathode rays depend upon the nature of gas present in the
cathode ray tube
11
934HMS. CUSH Tays a ys > Tauluk
Q9. Which series of lines of the hydrogen spectrum lie in the visible region?
11
935Rutherfords alpha particle scattering
experiment concluded that:
A. mass and energy are related
B. electrons occupy space around the nucleus
C. neutrons are buried deep in the nucleus
D. the point of impact with matter can be precisely determined
11
936c) T.
1
10111
(u) 0.04 10 11
27. The work function for sodium surface is 2.0 eV and
that for aluminium surface is 4.2 eV. The two metals are
illuminated with appropriate radiations so as to cause
photoemission. Then
(a) the threshold frequency for sodium will be less than
that for aluminium
(b) the threshold frequency of sodium will be more than
that of aluminium
(c) both sodium and aluminium will have the same
threshold frequency
(d) none of the above
0
c
.
11.
1
1
.
11
937According to Maxwell electromagnetic theory, through which path an electron should fall into the nucleus in
Rutherford’s atomic model:
A. Circular
B. Spiral
c. Zig-zag
D. Straight line
11
938Find the number of spectral line in
Paschen series emitted by atomic ( boldsymbol{H} )
when electron excited from ground
state to ( 70^{t h} ) energy level return back.
11
939U10
5. How many photons of a radiation of wavelength
1= 5 x 10 m must fall per second on a blackened plate
in order to produce a force of 6.62 x 10-‘N?
(a) 3 x 1019
(b) 5 x 1022
(c) 2 x 1022
(d) 1.67 x 1018
11
940Q. 24 Nickel atom can lose two electrons to form Ni2+ ion. The atomic number
of nickel is 28. From which orbital will nickel lose two electrons?
Toutermost
11
941What is common between given cations
and anions :
( boldsymbol{O}^{2-}, boldsymbol{F}^{-}, boldsymbol{N} boldsymbol{a}^{+}, boldsymbol{M} boldsymbol{g}^{2+}, boldsymbol{A} boldsymbol{l}^{3+} ? )
A. All have same ionic radii
B. All are isoelectronic species having 10 electrons
c. All of them belong to the third period
D. The nature of oxides of all the ions is basic
11
942Monazite sample contains ( 9 % T h O_{2} )
and ( 0.35 % U_{3} O_{8} . P b^{208} ) and ( P b^{208} ) are
the stable end products in the radioactive decay series of ( boldsymbol{T} boldsymbol{h}^{238} boldsymbol{q u a d a n d} quad mathbf{2 3 8} ) respectively. All

The isotopic ratio of ( P b^{208} T h^{232} ) was
found to be 0.104 . The half lives of Th
and ( U ) are ( 1.4 times 10^{10} ) years and ( 4.47 times )
( 10^{9} ) years, respectively. The time elapsed since the formation of monazite sample will be :
A. ( 1.34 times 10^{9} ) years
B . ( 2.01 times 10^{9} ) years
c. ( 1.41 times 10^{10} ) years
D. ( 4.47 times 10^{9} ) years

11
943In the equation ( boldsymbol{h} boldsymbol{v}=boldsymbol{h} boldsymbol{v}_{0}+frac{1}{2} boldsymbol{m}_{e} boldsymbol{v}^{2}, boldsymbol{v}_{0} )
is known as:
A. work function
B. velocity of ejected electron
c. threshold frequency
D. frequency of photon
11
944Write the symbols of the first ten elements in the periodic table with the atomic numbers.11
possess same:
A. wavelength
B. frequency
c. energy
D. velocity when passed through vacuum
11
946State whether the given reaction is true
or false:

Heavy water is used to control nuclear
reactions.
A. True
B. False

11
947Meitnerium is IUPAC official name of an
element with atomic number?
( A cdot 113 )
B. 118
( c cdot 104 )
D. 109
11
948What is the nucleos number of an
atom?
A. The number of electrons, neutrons and protons in the nucleus
B. The number of neutrons and protons in the nucleus
C. The number of neutrons in the nucleus
D. The number of protons in the nucleus
11
949Isobars have:
A. same mass number but different atomic number
B. same number of neutrons but different mass number
C. same difference between number of protons and neutrons
D. same mass number and atomic number
11
950Which of the following explains the
reason for nitrogen’s three unpaired
electrons?
A. Hund’s rule
B. Aufbau principle
c. Pauli’s principle
D. Heisenberg’s principle
11
951For which of the following particles will it be most difficult to experimentally verify the de-Broglie relationship?
A. an electron
B. a proton
c. an ( alpha ) particle
D. a dust particle
11
952Which of the following is true regarding
an ( N e ) atom with a mass number of 20
and an ( O^{2-} ) ion with a mass number of
( 16 ? )
A. They contain the same number of protons.
B. They contain the same number of neutrons.
C. They contain the same number of protons plus neutrons.
D. They are isoelectronic.
11
953What will be the ratio of ( C l^{35} ) and ( C l^{37} )
respectively in chlorine if the average atomic mass of chlorine is ( 35.5 ? )
A . 1:
B. 2:1
c. 3: 1
D. 3:2
11
954Write short note on solar spectrum or
continuous spectrum
11
955The electrons identified by quantum
numbers ( n ) and ( l, ) are as follows:
I. ( boldsymbol{n}=mathbf{4}, boldsymbol{l}=mathbf{1} )
Il. ( boldsymbol{n}=mathbf{4}, boldsymbol{l}=mathbf{0} )
III. ( boldsymbol{n}=mathbf{3}, boldsymbol{l}=mathbf{2} )
IV. ( n=3, l=1 )
If we arrange them in order of increasing energy, i.e. from lowest to highest, the correct order is:
A. ( I V<I I<I I I<I )
B. ( I I<I V<I<I I )
c. ( I<I I I<I I<I V )
D. III ( <I<I V<I I )
11
956Consider the isoelectronic species,
( N a^{+}, M g^{2+}, F^{-} ) and ( O^{2-} . ) The correct
order of increasing length of their radii is:
A ( cdot F^{-}<O^{2-}<M g^{2+}<N a^{+} )
B. ( M g^{2+}<N a^{+}<F^{-}<O^{2} )
C. ( O^{2-}<F^{-}<N a^{+}<M g^{2+} )
D. ( O^{2-}<F^{-}<M g^{2+}<N a^{+} )
11
957Which of the following nuclides belong
to actinium ( left(U^{235}right) ) series? This question has multiple correct options
( mathbf{A} cdot P b^{207} )
B . ( P o^{215} )
c. ( P_{o^{213}} )
D. ( _{1} H^{3} )
11
958Isoelectronic species have same number of electrons.
A. True
B. False
11
959Define an atomic orbital.11
960The number of neutrons present in the deuterium isotope of hydrogen is
A .2
B. 3
( c cdot 5 )
( D )
11
961The expression for de Broglie wavelength is :
A ( cdot p=frac{h}{lambda} )
в. ( p=frac{h}{2 lambda} )
c. ( _{p}=frac{2 pi}{h lambda} )
D. ( p=frac{2 pi}{lambda} )
11
962Chemical properties of of an
element are same, but their physical properties may be different
A. isotopes
B. isobars
c. neutron
D. proton
11
963The ( d ) -orbital having two lobes and one
doughnut is:
( mathbf{A} cdot d_{x^{2}-y^{2}} )
B. ( d_{z} )
c. ( d_{x y} )
D. ( d_{y z} )
11
964Which of the following is not a
drawback of Rutherford’s model?
A. Rutherford did not mention any direct link between the charge of the nucleus and the atomic mass
B. He did not mention the relation between the charge of the nucleus and atomic number
C. Both A and B
D. None of these
11
965Assertion
( mathbf{Psi} ) indicates the amplitude of electron –
wave
Reason
( mathbf{Psi}^{2} ) denotes the probability of finding an
electron in the space around the
nucleus.
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
11
966The p-orbitals are directed towards ( X, Y ) ( mathbf{Z} ) coordinates and are at right angles to
one another.
A. True
B. False
11
967( B e^{3+} ) and a proton are accelerated by same proton, their de-broglie wavelengths are in the ratio:
(Assume the mass of proton=mass of neutron)
A . 1:
B. 1:
( c cdot 1: 4 )
D. ( 1: 3 sqrt{3} )
11
968Calculate the minimum and maximum
number of electrons which may have
magnetic quantum number, ( boldsymbol{m}=+mathbf{1} ) and spin quantum number, ( s=-frac{1}{2} ) in Chromium ( (mathrm{Cr}) )
A . 0,1
в. 1,2
c. 4,6
D. 2,
11
969The frequency of the spectral line
obtained when the electron in ( n=3 ) of
Hydrogen atom drops to the fround
state is:
A ( cdot 2.925 times 10^{15} ) Hertz
B . ( 2.925 times 10^{13} ) Hertz
C . ( 2.925 times 10^{14} ) Hertz
D. ( 36559 times 10^{10} ) Hertz
11
970Which of the following observations
were obtained from ( alpha ) -particle
scattering experiment?
A. Most of the fast moving ( alpha ) -particles passed straight through the gold foil
B. Some of the ( alpha ) -particles were deflected by the foil by small angles
c. One out of every 12000 particles appeared to rebound
D. All of the above
11
971What is the shape of d-orbital?
A. spherical
B. dumb bell
c. double dumb bell
D. no definite shape
11
972Assertion
e/m ratio of anode rays is independent
of nature of gas.
Reason
All anode rays are protons
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
11
973Write all the four quantum no.for ( boldsymbol{p}- )
electrons of ( _{7} mathbf{N}^{14} )
A ( cdot n=3, l=2, m=-1,0,+1 ; s=+frac{1}{2} ) and ( -frac{1}{2} )
B. ( n=2, l=1, m=-1,0,+1 ; s=+frac{1}{2} ) or ( -frac{1}{2} )
c. ( _{n=2, l=1, m=-1,0,+1 ; s=+frac{1}{2}} )
D. ( n=2, l=0, m=0 ; s=+frac{1}{2} ) and ( -frac{1}{2} )
11
974( B e^{3+} ) and a proton are accelerated by
the same potential, their de-Broglie wavelenghts have the ratio (assume
mass of proton ( = ) mass of neutron):
A .1: 2
B. 1: 4
c. 1: 1
D. ( 1: 3 sqrt{3} )
11
975The ratio of the energy of a photon of ( 2000 A ) wavelength radiation to that of ( 4000 A ) radiation is:
A ( cdot frac{1}{4} )
B. 4
( c cdot frac{1}{2} )
D. 2
11
976Calculate maximum number of
electrons in ( _{25} M n ) which have ( n=3, m=0 )
and ( s==1 / 2 )
11
977An electron of a velocity ( x ) is found to have a certain wavelength. The velocity to be possessed by the neutron to have half the de Broglie wavelength possessed by electron is:
A ( cdot frac{x}{1840} )
в. ( frac{x}{920} )
c. ( 3680 x )
D. ( frac{x}{3680} )
11
978Which one of the following has a larger wave number?
A . Red
B. Blue
c. Green
D. Violet
11
979Which of the following statement about
quantum number is correct?
This question has multiple correct options
( A . ) If the value of ( l=0, ) the electron distribution is
spherical
B. The shape of orbital is given by subsidiary quantum number
C. The Zeeman’s effect is explained by magnetic quantum number
D. The spin quantum number gives the orientations of electron cloud
11
980Out of first 100 elements no.of elements
having electrons in ( 3 d ) orbital (in their complete electronic configuration) are:-
A . 80
в. 100
c. 40
D. 60
11
981Principal quantum number gives the
of an electron and its distance
from the nucleus.
A. angular momentum
B. energy
c. velocity
D. centrifugal force
11
982Elements after atomic number 103
have not been discovered till now. If an
element with atomic number 106 were
ever discovered which of the following electronic configuration will it possess.
( mathbf{A} cdot[R n] 5 f^{14} 6 d^{4} 7 s^{1} )
B ( cdot[R n] 5 f^{14} 6 d^{5} 7 s^{1} )
( mathbf{c} cdot[R n] 5 f^{14} 6 d^{6} 7 s^{0} )
D cdot ( [R n] 5 f^{14} 6 d^{1} 7 s^{2} 7 p^{3} )
11
983A ( d ) -subshell in an atom in the presence
and absence of magnetic field is:
A . five-fold degenerate, non-degenerate
B. feven-fold degenerate, non-degenerate
c. five-fold degenerate, five-fold degenerate
D. non-degenerate, five-fold degenerate
11
984Assertion
A spectral line will be observed for
( 2 P_{z}-2 P_{y} ) transition
Reason
The energy of ( 2 P_{x} ) and ( 2 P_{y} ) orbitals is
the same
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
11
985011
986Summarise the rules for writing of
distribution of electrons in various
shells for the first eighteen elements.
11
987Isotopes of iodine is used in
the treatment of goiter.
A. ( I-132 )
в. ( I-133 )
c. ( I-13 )
D. ( I-130 )
11
988I : Some alpha particles shot at a thin
metal foil are reflected back toward the
source.
II : Alpha particles shot at thin metal foil sometimes approach the nuclei of the metal atoms head-on and arc thus
repelled.
11
989The shape of the orbital with the value of ( l=2, m=0 ) is :
A. spherical
B. double dumb-bell
c. trigonal planar
D. square planar
11
990For which of the species, Bohrs theory is not applicable?
( mathbf{A} cdot B e^{+3} )
B. ( L i^{+2} )
( mathbf{c} cdot H e^{+2} )
D. ( H )
11
991The electronic configuration of
potassium is 2,8,8,1 and not 2,8,9
11
992An atom of an element has two
electrons in the M shell. Identify its atomic number.
A . 10
B. 12
( c cdot 14 )
D. 15
11
993What is the effect on specific charge if the speed of electron increases?
A. Decreases
B. Increases
c. Remains same
D. None
11
994The uncertainty in the position of an electron ( left(text { mass }=mathbf{9 . 1} times mathbf{1 0}^{-mathbf{2 8}} mathbf{g}right) )
moving with a velocity of ( 3.0 times ) ( 10^{4} c m^{-1} ) accurate up to ( 0.011 %, ) will
be:
A . ( 1.92 mathrm{cm} )
B. 7.68 ст
c. ( 0.175 mathrm{cm} )
D. ( 3.84 mathrm{cm} )
11
995The band spectrum is caused by:
A . molecules
B. atoms
c. any substance in solid state
D. any substance in liquid state
11
996The Schrodinger wave equation for hydrogen atom is:
( mathbf{Psi}_{2 s}=frac{1}{4 sqrt{2} pi}left(frac{1}{a_{0}}right)^{3 / 2}left[2-frac{r_{0}}{a_{0}}right] e^{-r / a_{0}} )
node in ( 2 s ) be at ( r_{0}, ) then find ( r ) in terms
of ( a_{0} )
A ( cdot frac{a_{0}}{2} )
В. ( 2 a_{0} )
c. ( sqrt{2} a_{0} )
D. ( frac{a_{0}}{sqrt{2}} )
11
997Which is the correct relationship between wavelength and momentum of particles?
A ( cdot lambda=frac{h}{p} )
B. ( pi=frac{h}{p} )
c. ( p=frac{lambda}{h} )
D. ( h=frac{P}{lambda} )
11
998In which of the following pairs do the two species resemble each other closely in chemical properties?
A ( cdot frac{1}{1} H ) and ( _{1}^{2} H )
B. ( _{8}^{16} O ) and ( _{8}^{16} O^{2-} )
C ( cdot frac{24}{12} M g ) and ( _{12}^{24} M g^{2+} )
D. ( frac{14}{7} N ) and ( frac{14}{7} N^{3}- )
11
999Which of the following quantities will be zero for alpha particles at the point of closest approach to the gold atom in Rutherford’s scattering of alpha particles?
A. Acceleration
B. Kinetic energy
c. Potential energy
D. Electrical energy
11
1000Q8. In a hydrogen atom, the energy of an electron in first Bohr’s orbit is 13.12 10°
mol-. What is the energy required for its excitation to Bohr’s second orbit?
.
11
1001Q14. An electron beam after hitting a neutral crystal produces a diffraction pattern? What do you
conclude?
11
1002Penetration power of proton is
A. more than electron
B. less than electron
C. equal to electron
D. none of these
11
1003An atom has mass number 23 and
atomic number 11. How many protons, electrons and neutrons are present in
the atom?
A. 11,12,13
B. 11,11,12
c. 11,11,13
D. 11,14,15
11
1004The orbital angular momentum and
angular momentum (classical
analogue) for the electron of ( 4 s ) -orbita
are respectively, equal to:
A ( cdot sqrt{12} frac{h}{2 pi} ) and ( frac{h}{2 pi} )
B. zero and ( frac{2 h}{pi} )
c. ( sqrt{6} h ) and ( frac{2 h}{pi} )
D. ( sqrt{2} frac{h}{2 pi} ) and ( frac{3 h}{2 pi} )
11
1005The maximum kinetic energy of electron emitted in the photoelectric effect linearly depends on the of
A. temperature
B. amplitude
c. number
D. frequency
11
1006Atomic number of strontium ( (S r) ) is
equal to:
A . 28
B. 38
( c cdot 42 )
D. 34
11
1007The average binding energy per nucleon is maximum for the nucleus:
( mathbf{A} cdot_{2} H e^{4} )
B ( cdot_{8} O^{16} )
( mathbf{c} cdot_{26} F e^{56} )
D・ ( _{92} U^{238} )
11
1008A bulb of ( 40 mathrm{W} ) is producing a light of wavelength ( 620 mathrm{nm} ) with ( 80 % ) of efficiency, then the number of photons emitted by the bulb in 20 seconds are ( left.mathbf{1} e boldsymbol{V}=mathbf{1 . 6} times mathbf{1 0}^{-mathbf{1 9}} mathbf{J}, boldsymbol{h} boldsymbol{c}=mathbf{1 2 4 0 0} e boldsymbol{V}right) )
( mathbf{A} cdot 2 times 10^{18} )
B . ( 10^{18} )
c. ( 10^{21} )
D. ( 2 times 10^{11} )
11
1009Maximum number of electrons in a sub
shell is given by:
A ( cdot(2 l+1) )
B. ( 2(2 l+1) )
( mathbf{c} cdot(2 l+1)^{2} )
D. ( 2(2 l+1)^{2} )
11
101053. If the K, radiation of Mo (Z = 42) has a wavelength of
0.71 Å find the wavelength of the corresponding radiation
of Cu (Z = 29)
(a) 1
(b) 2 Å
(c) 1.52 Å
(d) 1.25 Å
11
1011Which of the following pairs represents isobars?
A ( cdot 2^{3} mathrm{He} ) and ( _{2}^{4} mathrm{He} )
B ( cdot frac{24}{12} mathrm{Mg} ) and ( _{12}^{25} mathrm{Mg} )
( mathbf{c} cdot_{19}^{40} K operatorname{and}_{20}^{40} C a )
11
1012Which of the following configurations corresponds to element of highest ionisation energy?
A ( cdot 1 s^{2}, 2 s^{1} )
B . ( 1 s^{2}, 2 s^{2}, 2 p^{3} )
C. ( 1 s^{2}, 2 s^{2}, 2 p^{2} )
D. ( 1 s^{2}, 2 s^{2}, 2 p^{6}, 3 s^{1} )
11
10134. Magnetic moment due to the motion of the electron in nth
energy of hydrogen atom is proportional to
(a) n
(b) nº
(c) n
(d) n?
11
1014Cathode rays have:
A. mass only
B. charge only
c. no mass and no charge
D. mass and charge both
11
1015What is the distance of closest
approach to the nucleus of an ( alpha ) particle which undergoes scattering by
( 180^{circ} ) in Geiger-Marsden experiment?
11
1016Match List 1 with List 2:11
1017Filling the blanks. Both elements and compounds are substances.11
1018A negatively charged particle called Negatron was discovered. In the Millikan’s oil-drop experiment, the charges of the oil-drops in five experiments are reported as ( 3.2 times )
( 10^{-19} ) coulomb; ( 4.8 times 10^{-19} ) coulomb
( 6.4 times 10^{-19} ) coulomb
11
1019The cathode rays tube experiments
carried out by J.J. Thomson
demonstrated that:
A. ratio of charge to-mass for the particles of the cathode rays varies as different gases are placed in the tube
B. the mass of an atom is essentially all contained in its very small nucleus.
C. cathode rays are streams of negatively charged ions.
D. the charge-to-mass ratio for an electron is same for all gases.
11
1020What is the total value of ( m ) for all
electrons in ( mathrm{N} ) atom?
11
1021( M^{-2} ) configure is ( 1 s^{2} 2 s^{2} 2 p^{6}, ) then
( M^{+2} ) configuration will be :
A ( cdot 1 s^{2} )
B. ( 1 s^{2} 2 s^{2} )
C ( cdot 1 s^{2} 2 s^{2} 2 p^{2} )
D. ( 1 s^{2} 2 s^{2} 2 p^{4} )
11
1022How long would it take a radio-wave of frequency, ( 6 times 10^{3} ) sec ( ^{-1} ) to travel from
Mars to the Earth, a distance of ( 8 times ) ( 10^{7} k m )
11
1023( 18 A r^{40} ) and ( _{19} K^{40} ) are a pair of
A. isomers
B. isobars
c. isotopes
D. isotones
11
1024An element has 8 electrons in ( 4 d- )
subshell. Show the distribution of 8
electrons in the ( d ) -orbitals of the
element within small rectangles.
11
1025J.J. Thomson found that:
A. Electron have negligible mass
B. It have one unit of negative charge
c. Option A and B both
D. None of the above
11
1026If an electron is travelling at ( 200 m / s ) within 1 m/ ( s ) uncertainty, what is the theoretical uncertainty in its position in ( mu m(text { micrometer }) ? )
A . 14.5
B . 29
c. 58
D. 114
11
1027The number of photons emitted in 10 hours by a ( 60 mathrm{W} ) sodium lamp are:
(take ( lambda ) of photon ( =6000 mathrm{A}, h c=12400 )
eVA, ( h= ) Planck’s constant, ( c= ) speed of
light)
A ( cdot 6.50 times 10^{24} )
B. ( 6.40 times 10^{23} )
c. ( 8.40 times 10^{23} )
3
D. 3.40 ( times 10^{23} )
11
1028Which of the following species are expected to have spectrum similar to hydrogen? This question has multiple correct options
A ( . H e^{+} )
B. ( H e^{2+} )
( c cdot L i^{2} )
( mathbf{D} cdot L i^{+} )
11
1029If an electron is moving with a velocity of ( 1.1 times 10^{6} mathrm{ms}^{-1} ) de broglie wave
length approximately is:
A ( cdot 4.1 times 10^{-11} mathrm{m} )
В . ( 4.9 times 10^{-9} mathrm{m} )
c. ( 7 times 10^{-10} m )
D. ( 3.306 times 10^{-8} mathrm{m} )
11
1030Assertion
The mass number of hydrogen is equal
to its atomic number
Reason
H-atom has no neutrons
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
11
1031Number of angular nodes for ( 4 d ) orbital
is
A . 4
B. 3
( c cdot 2 )
( D )
11
1032An electron, practically at rest, is initially accelerated through a potential difference of 100 volts. It then has a de
Broglie wavelength ( =lambda_{1} A . ) It then get
retarded through 19 volts and then has
a wavelength ( lambda_{2} ). A further retardation
through 32 volts changes the wavelength to ( lambda_{3} A, ) what is ( frac{lambda_{3}-lambda_{1}}{lambda_{1}} ? )
11
1033Select the correct option.
(a) Energy of ground state of ( boldsymbol{H} e^{+} )
[
(i)+6.04 e v
]
(b) Potential energy of I orbit of ( boldsymbol{H}- )
atom
(ii) -27.2 eV
(c) Kinetic energy of II excited state of
( boldsymbol{H} e^{+} )
(iii) +54.4 ev
(d) Ionisation potential of ( boldsymbol{H} boldsymbol{e}^{+} )
(iv) ( -54.4 mathrm{eV} )
( A cdot a(i), b ) (ii) ( , c ) (iii), d (iv)
B. a (iv), b (iii), c (ii), d(i)
( c cdot a(i v), b(i i), c(i), d ) (iii)
D. a (ii), b (iii), c (i), d (iv)
11
1034For ( n=3 ) energy level, number of orbitals of all kind that are possible is:
A . 9
B. 7
( c cdot 8 )
D. 10
11
1035Who said that cathode rays consist of negatively charged particles?
A. Dalton
B. Rutherford
D. J.J. Thomson
11
1036How will you find out the maximum number of electrons in the main energy level?
A . ( n )
B. ( n^{2} )
( c cdot 2 n^{4} )
D. ( 2 n^{2} )
11
1037Calculate the wavelength for the emission transition if it starts from the
orbit having radius ( 1.3225 mathrm{nm} ) and ends at ( 211.6 mathrm{pm} . ) Name the series to which this transition belongs and the region of
the spectrum.
11
1038Calculate the wavelength of an electron moving with a kinetic energy of
( 18.62 times 10^{-25} J )
11
1039Match the items in List 1 with those in
List 2
11
1040Who was the first scientist to propose a
model for the structure of an atom?
A. J.J. Thomson
B. Dalton
c. Ernest Rutherford
D. E. Goldstein
11
1041If uncertainties in the measurement of
position and momentum of an electron are equal, calculate uncertainty in the measurement of velocity.
11
1042When an electron in hydrogen spectrum jumps from ( n=7 ) to ( n=2 ), the total
number of spectral lines possible are:
A . 21
B . 15
( c .5 )
D.
11
1043Light travels with a speed of ( 3 times 10^{8} ) ( {m s} wedge{-1} . ) The distance travelled by light in 1 femto second is:
A. ( 0.03 mathrm{mm} )
B. ( 0.003 m m )
( mathbf{c} .3 m m )
D. ( 0.0003 mathrm{mm} )
11
1044Which is correct with respect to ‘p’ orbitals?
A. They are spherical
B. They have a strong directional character
c. They are five fold degenerate
D. They have no directional character
11
1045The aufbau principle is violated in
( 2 s )
[
]
This question has multiple correct options
( mathbf{A} )
( uparrow downarrow quad uparrow downarrow )
B.
( uparrow )
( uparrow downarrow )
[
uparrow
]
c.
( uparrow downarrow )
( uparrow )
( uparrow )
D.
( uparrow downarrow quad uparrow downarrow )
11
1046Atomic number of nitrogen is ( 7 . ) The number of protons in Nitrogen atom is equal to
( A cdot 14 )
B. 7
( c cdot 2 )
D. 15
11
1047The carbonate of a metal is
isomorphous (similar formula) with magnesium carbonate and contains 6.091 percent of carbon. The atomic weight of metal is:
A . 24
B. 56
( c cdot 137 )
D. 260
11
1048When a hydrogen sample in the ground state is bombarded then what potential is required to accelerate electron so
that first Paschen line is emitted, then
calculate the energy difference?
A . 2.55
B. 0.65
c. 12.09
D. 12.75
11
1049According to JJ Thomson’s atomic model, negative charges are embedded
in:
A. A lump of positive charge
B. A lump of neutral particles
c. A lump of small atoms
D. The nucleus
11
1050A neutron breaks into a proton and an electron. This decay of neutron is
accompanied by the release of energy. Assuming that ( 50 % ) of the energy is produced in the form of electromagnetic radiation, what will be the frequency of radiation produced. Will this photon be sufficient to cause ionization of aluminum? In case it is
able to do so what will be the energy of the electron ejected from the aluminum
atom
( boldsymbol{I} boldsymbol{E}_{1} ) of ( boldsymbol{A l}=mathbf{5 7 7} mathrm{KJ} / mathrm{mol} )
11
1051Members of which of the following have similar chemical properties?
A. Isotope
B. Isobars
c. Allotropes
D. Both isotopes and allotropes
11
1052According to Bohr’s theory of hydrogen atom, which of the following is quantized for an electron?
A. Acceleration
B. Velocity
c. Angular momentum
D. Angular acceleration
11
1053An atom with the same number of
protons but a different number of
neutrons is :
A . a molecule
B. a mixture of compound
c. an isotope
D. an isomer
E. an acid salt
11
1054a) Assign the position of the element having outer electronic configuration in the periodic table
(i) ( n s^{2} n p^{4} ) for ( n=3 )
( (n-1) d^{2} n s^{2} ) for ( n=4 )
b) The size of ( N a^{+} ) cation is smaller
than ( N a . ) Explain
11
1055Dalton’s atomic theory was not
accepted fully:
A. when atoms combine It must be presumed to be a binary one, unless some cause appear to the contrary.
B. when elements react, their atoms sometimes combine in more than one simple, whole-number ratio.
C. elements are characterized by the mass of their atoms.
D. None of the above
11
1056electron of hydrogen atom in a spherical shell of infinitesimal thickness ( d r, ) at a
distance r from the nucleus. The volume
of this shell is ( 4 pi r^{2} d r . ) The qualitative
sketch of the dependence of P on r is:
( mathbf{A} )
B.
( c )
D.
11
1057Show that the circumference of the Bohr
orbit for the hydrogen atom is an integral multiple the de-Broglie wavelength associated with the
electron revolving around orbit.
11
1058Neutron was discovered by:
A. J.J. Thomson
c. Rutherford
D. Priestley
11
105948. Let o ng and ac denote the wavelengths of the X-rays
of the Ką Kg and La lines in the characteristic X-rays for
a metal
(a) nada >d; (b) da >d;> da
1 1 1
1 1 1
(d) = += ==
а в Ло
(c)
AB
na
na
2 TO
V
1….
.
11
1060An electron in a hydrogen atom in its ground state absorbs energy equal to the ionization energy of ( L i^{+2} . ) The wavelength of the emitted electron is:
A. ( 3.32 times 10^{-10} mathrm{m} )
в. 1.17 А
c. ( 2.32 times 10^{-9} mathrm{nm} )
D. 3.33 pm
11
1061What is the energy associated with ( 3^{r d} )
energy shell of hydrogen atom?
В. ( -0.342 times 10^{-19} mathrm{J} )
c. ( -0.126 times 10^{-19} mathrm{J} )
D. ( -2.41 times 10^{-19} mathrm{J} )
11
106223. Let the potential energy of a hydrogen atom in the
state be zero. Then, its energy in the first excited State
be
(a) 10.2 eV
(b) 13.6 eV
(c) 23.8 eV
(d) 27.2 eV
11
1063Give reason for the following:
The mass number of an atom is slightly less than the actual atomic mass.
11
1064The values of Planck’s constant is
( 6.63 times 10^{-34} J s . ) The velocity of light is
( 3.0 times 10^{8} m s^{-1} . ) Which value is closest
to the wavelength in nanometres of a quantum of light which frequency of
( 8 times 10^{15} s^{-1} ? )
( mathbf{A} cdot 5 times 10^{-18} )
B. ( 4 times 10^{1} )
( c cdot 3 times 10^{7} )
D. ( 2 times 10^{-25} )
11
1065Assume that the potential energy of a hydrogen atom in its ground state is
zero. Then its total energy in the first
excited state will be:
A . ( 13.6 e V )
в. 27.2eV
c. ( 23.8 e V )
D. ( 10.2 e V )
11
1066If an electron is moving with velocity
( 500 m s^{-1}, ) which is accurate up to
( 0.005 % ) then calculate uncertainty in its
position. ( left[boldsymbol{h}=mathbf{6 . 6 3} times mathbf{1 0}^{-mathbf{3 4}} boldsymbol{J}-right. )
( s, ) mass of electron ( =9.1 times )
( left.mathbf{1 0}^{-mathbf{3 1}} quad boldsymbol{K} boldsymbol{g}right] )
11
1067( 1^{s t} ) excitation potential for the ( mathrm{H}- ) like(hypothetical)sample is 24V. Choose the correct statement.
This question has multiple correct options
A ( cdot 1^{s t} ) excitation potential for the ( mathrm{H} ) like(hypothetical)sample is 24v
B. Ionisation energy of the sample is 32 ev
C. Binding energy of ( 3^{r d} ) excited state is 2 ev
D. ( 2^{text {nd }} ) excitation potential of the sample is ( frac{32 times 8}{9} V )
11
10682
1 2
21. Electrons are accelerated in television tubes through
potential differences of about 10 kV. The highest
frequency of the electromagnetic waves emitted when
these electrons strike the screen of the tube is
(a) 2.4 x 1018 Hz
(b) 3.6 x 1018 Hz
(c) 2.2 x 1017 Hz (d) 3.2 x 1016 Hz
11
1069Energy of H- atom in the ground state is ( -13.6, ) Hence energy in the second excited state is:
A . -6.8ev
B. – 3.4ev
c. -1.51ev
D. -4.3ev
11
1070Q3. What are degenerate orbitals?11
1071The mass number of an atom is the
sum of the number of protons and number of neutrons in an atom.
If it is true enter 1 else 0
11
1072Energy of electron in first excited state
of ( H ) -atom is:
A. ( -13.12 times 10^{5} mathrm{J} / mathrm{mol} )
B. ( -3.28 times 10^{5} mathrm{J} / mathrm{mol} )
c. ( 13.12 times 10^{3} J / ) mol
D. ( 3.28 times 10^{2} J / ) mol
11
1073In Thomson’s plum-pudding model,
electrons are not:
A. negatively charged
B. present in every type of atom
C . collected together in the center of the atom
D. scattered throughout a blob of positively charged material
11
1074An atom of an element has 3 electrons
in ( 4 p ) subshell. The atomic number of
the element is :
A . 31
B. 33
c. 35
D. 34
11
1075Which of the following is not the basic postulate(s) of Dalton’s atomic theory?
A. Atoms are neither created nor destroyed in a chemical reaction
B. In a compound, the relative number and kinds of atom are constant
c. Atoms of all elements are alike, including their masses
D. Each element is composed of extremely small particles called atoms
11
1076Which of the properties of isotopes of an element is different?
A. First ionisation enthalpy
B. Effective nuclear charge
c. Electron affinity
D. Melting point and boiling point
11
1077The element having electronic configuration.
( [boldsymbol{K} boldsymbol{r}] boldsymbol{4} boldsymbol{d}^{10} boldsymbol{4} boldsymbol{f}^{14} boldsymbol{5} boldsymbol{s}^{2} boldsymbol{5} boldsymbol{p}^{6} boldsymbol{5} boldsymbol{f}^{2} boldsymbol{6} boldsymbol{s}^{2} ) belongs
to
A. s-block
B. p-block
c. d-block
D. f-block
11
1078The binding energy of electrons in a metal is ( 193 mathrm{kJ} mathrm{mol}^{-1} ). The threshold
frequency of the metal is:
A. ( 8.83 times 10^{14} mathrm{s}^{-1} )
B. 4.83 ( times 10^{14} mathrm{s}^{-1} )
c. ( 5.83 times 10^{14} mathrm{s}^{-1} )
D. 6.83 ( times 10^{14} mathrm{s}^{-1} )
11
1079The probability of finding the electron in
( boldsymbol{p}_{boldsymbol{x}} ) -orbital is:
This question has multiple correct options
A. maximum on two opposite sides of the nucleus along ( x ) -axis
B. zero at the nucleus
c. same on all the sides around the nucleus
D. zero on the ( z ) -axis
11
1080( mathbf{2} boldsymbol{s} stackrel{I}{rightarrow} mathbf{2} boldsymbol{p} stackrel{I I}{rightarrow} mathbf{3} boldsymbol{d} stackrel{I I}{rightarrow} mathbf{3} boldsymbol{p} stackrel{I V}{rightarrow} mathbf{4} boldsymbol{s} stackrel{boldsymbol{V}}{rightarrow} mathbf{2} boldsymbol{p} )
The electronic transitions show above
are observed when lithium atoms are
sprayed into a hot flame. The various
transitions are numbered for
identification. Which of these
transitions would result in emission of
A. I and II only
B. I and III only
c. I and v only
D. III and IV only
E. III and v only
11
1081The mass of an electron is ( 9.1 times 10^{-31} mathrm{kg} )
If its kinetic energy is ( 3.0 times 10^{-25} mathrm{J} )
calculate its wave length.
11
1082Calculate the number of
revolutions/sec around the nucleus of
an electron placed in III orbit of ( boldsymbol{H} ) -atom
A ( cdot 1.44 times 10^{12} )
B . ( 7.29 times 10^{7} )
c. ( 15.33 times 10^{14} )
D. ( 2.44 times 10^{14} )
11
1083Assertion
Atom is electrically neutral
Reason
A neutral particle, neutron is present in
the nucleus of the atom
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
11
1084Electromagnetic radiation of wavelength ( 242 mathrm{nm} ) is just sufficient to ionise the sodium atom. What should
be ionization energy of sodium atom in
order of ( 10^{-19} ?left(c=3 times 10^{8} mathrm{ms}^{-1}, h=right. )
( 6.626 times 10^{-34} mathrm{Js} )
A . 8.2
B. 8
c. 9
D. 9.2
11
1085The value of Bohr radius for hydrogen
atom is:
A ( .0 .529 times 10^{-8} mathrm{cm} )
B . ( 0.529 times 10^{-10} mathrm{cm} )
c. ( 0.529 times 10^{-6} mathrm{cm} )
D. ( 0.529 times 10^{-12} mathrm{cm} )
11
1086An electron in a Bohr orbit of a hydrogen
atom with the quantum number ( n_{2} ) has
an angular momentum ( 4.2176 times ) ( 10^{-34} k g m^{2} s^{-1} . ) If electron drops from
this level to the next lower level, then the
wavelength of this line is:
A ( cdot 18.75 times 10^{-7} m )
B. ( 1.87 times 10^{-7} mathrm{m} )
c. ( 187.5 times 10^{-7} mathrm{m} )
D. ( 0.187 times 10^{-7} m )
11
108732. The ratio between total acceleration of the electron in
singly ionized helium atom and hydrogen atom (both in
ground state) is
(a) 1
. (b) 8
(c) 4
(d) 16
11
1088Q. 39 Table-tennis ball has mass 10 g and speed of 90 m/s. It spee
measured within an accuracy of 4%, what will be the uncertainty in
speed and position?
11
1089State True or False.
Gamma rays produce maximum ionization in gases.
A. True
B. False
11
1090Which of the following species has less number of protons than the number of
neutrons?
This question has multiple correct options
A ( cdot frac{12}{6} C )
В . ( _{9}^{9} F )
( mathbf{c} cdot_{11}^{23} N a )
D ( cdot frac{24}{12} M g )
11
1091Calculate the wave number of the
highest energy transition in the Balmer series of the hydrogen atom:
( left[boldsymbol{R}_{boldsymbol{H}}=mathbf{1 0 9 6 7 8 c m}^{-1}right] )
A ( .27419 .5 mathrm{cm}^{-1} )
В. 2741.95 ( c m^{-1} )
c. ( 274.195 mathrm{cm}^{-1} )
D. 274195.1 ( c m^{-} )
11
1092Consider the following statements and
predict the wrong statement(s)
a. Half filled and fully filled orbitals have greater stability due to greater exchange energy and symmetrical
distribution
b. The energy of ( 3 s ) orbital is less than
( 3 p ) orbital for hydrogen atom.
c. The uncertainty principle is ( Delta boldsymbol{E} times ) ( Delta t leq frac{h}{4 pi} )
( boldsymbol{d} boldsymbol{E}=-boldsymbol{2} . boldsymbol{1} boldsymbol{7} boldsymbol{8} times boldsymbol{1} boldsymbol{0}^{-18}left(frac{boldsymbol{Z}^{2}}{boldsymbol{n}^{2}}right) boldsymbol{J} boldsymbol{a t o m}^{-1} )
can be used to calculate the change in
energy when the electron changes orbit in H-atom
A. b and conly
B. b, c and donly
c. a and b only
D. a and donly
11
1093A proton is accelerated to one-tenth of the velocity of light. If its velocity can be measured with a precision ( pm 1 % ), then its uncertainty in position is:
A ( cdot 1.05 times 10^{-13} m )
В. ( 1.13 times 10^{-13} mathrm{m} )
c. ( 1.15 times 10^{-13} mathrm{m} )
D. ( 1.25 times 10^{-13} mathrm{m} )
11
1094Which of the following statements are
correct for an electron that has ( n=4 )
and ( m=-2 ? )
This question has multiple correct options
A. The electron may be in a ( d ) -orbital
B. The electron is in the ( 3^{r d} ) -orbital
C . The electron may be in a ( p ) -orbital
D. The electron must have the spin quantum number ( = ) ( 1 / 2 )
11
1095Carbon-dating uses carbon isotope with
number of neutrons eight
if true enter 1 , else enter 0
11
1096The net charge inside an atom is zero
because:
A. the magnitude of positive charge is more than negative charge inside atom
B. the magnitude of positive and negative charge is same inside atom
C. the magnitude of positive and negative charge is same outside atom
D. the magnitude of positive charge is less than negative charge inside atom
11
109728. The ratio of maximum to minimum possible radiation
energy in Bohr’s hypothetical hydrogen atom is equal to
(a) 2
(b) 4
(c) 4/3
(d) 3/2
11
1098The ( t_{1 / 2} ) for ( ^{14} mathbf{C} ) in (i) ( ^{14} mathrm{CO}_{2} ) (ii) ( ^{14} C_{6} mathbf{H}_{12} mathrm{O}_{6}(text { iii }) ) coal containing ( ^{14} mathbf{C}(i boldsymbol{v}) )
cellulose containing ( ^{14} mathbf{C} ) is :
( mathbf{A} cdot operatorname{more} operatorname{in}^{14} mathrm{CO}_{2} )
B. more in coal containing ( ^{14} mathrm{C} )
c. more in ( ^{14} C_{6} mathrm{H}_{12} mathrm{O}_{6} )
D. same in all species
11
1099Which of the following is true regarding
an ( N e ) atoms with a mass number of 20
and ( O^{2-} ) ion with a mass number of ( 16 ? )
A. They contain the same number of protons
B. They contain the same number of neutrons
C. They contain the same number of protons plus netrons
D. The are isoelectronic
E. They are isomers
11
1100A sample of ( H e^{+} ) ions in a gaseous
state had all ions in ( n^{t h} ) excited state.
This sample on returning to ground state emits a total of 28 spectral lines.
Value of ( n ) is:
( A cdot 8 )
B. 7
( c cdot 6 )
D. 5
11
1101In which region of electromagnetic spectrum does the Balmer series lie?
A. UV
B. Visible
c. Infrared
D. Far infrared
11
1102Elements are characterized by the
of their atoms.
A. electrons
B. mass
c. protons
D. shape
11
1103The de-Broglie wavelength associated
with a material particle is :
A. directly proportional to its energy
B. directly proportional to momentum
C. inversely proportional to its energy
D. inversely proportional to momentum
11
1104Bohr’s theory is not applicable to:
This question has multiple correct options
A. He
B . ( L i^{2} )
( mathrm{c} cdot mathrm{He}^{2} )
D. the H-atom
11
1105Which of the following set of quantum number represents highest energy of an atom?
( A cdot_{n=3, mid=2, m=1, s=+frac{1}{2}} )
B. ( n=3,1=2, m=1, s=-frac{1}{2} )
( c cdot_{n=4,1=0, m=0, s=+frac{1}{2}} )
D. ( n=3, s=+frac{1}{2} )
11
1106What is shortest wavelength line in the
Paschen series of ( L i^{2+} ) ion?
11
1107The total number of orbitals in the fifth
energy level is:
A . 5
B. 10
c. 18
D. 25
11
1108If radius of ( 3^{r d} ) orbit of ( L i^{2+} ) ion is ‘x’ ( mathrm{cm} )
then de-broglie wavelength of electrons
in the ( 1^{s t} ) orbit is :
( A cdot frac{2 pi x}{3} mathrm{cm} )
в. ( 6 pi x ) ст
c. ( 3 pi x ) ст
D. ( frac{2 pi x}{6} mathrm{cm} )
11
1109Calculate the radius of first orbit in
( H e^{+} ) ion.
A ( cdot 0.2645 A^{circ} )
B . 26.45 A ( ^{text {о }} )
c. ( 0.2465 times 10^{-12} )
D. none of these
11
1110A ( 3 p ) -orbital has:
A. two non-spherical nodes.
B. two spherical nodes.
C . one spherical and one non-spherical node.
D. one spherical and two non-spherical nodes.
11
1111Determine the ratio of charge to mass (specific charge) for electron and alpha particle.
A .2:
B. 1: 1
c. 1: 2
D. None of these
11
1112The number of occupied sub-shell in ( mathrm{Cr} )
( + ) is :
A . 3
B. 4
( c cdot 7 )
D. 6
11
1113The effective atomic number of Mn,in
( M n_{2}(C O)_{10} ) is
A . 36
B. 38
( c cdot 32 )
D. 34
11
1114Heisenberg uncertainty principle is not valid for :
This question has multiple correct options
A. moving electrons
B. motor car
c. stationary particles
D. all of the above
11
1115In an atom, the differentiating electron
enters into 7 s sub shell. The number of
incomplete shells in the atom could be:
A . 1
B . 2
( c .3 )
D.
11
1116Write electronic configurations of the elements (number in the brackets
indicate atomic numbers) potassium ( (mathbf{1 9}) )
11
1117What are the characteristics of isobars?
A. They have different atomic numbers.
B. They have same electronic configuration.
C. They have same number of neutrons.
D. All of the above
11
1118In a hydrogen atom, the energy of an electron in an orbit is -3.4 eV. When it is
excited to the next higher energy level and comes back to ground state, calculate the wave length of emitted
( mathbf{A} cdot 9 times 10^{-7} m )
В. ( 9 times 10^{-9} m )
( mathbf{c} cdot 9 A^{circ} )
D. none of these
11
1119No. of wave in third Bohr’s orbit of
hydrogen is
11
1120In which energy level is the outer electron in rubidium located?
A . 85
B. 2
c. 37
( D )
( E .5 )
11
1121Analyze the Photoelectron Spectra.
What is the identity of the element?
( A cdot H )
в. ( H e )
( c cdot L i )
D. ( B e )
11
1122A dust particle has mass equal to ( 10^{-11} g, ) diameter ( 10^{-4} c m ) and velocity ( 10^{-4} mathrm{cm} / mathrm{s} . ) The error in measurement of
velocity is ( 0.1 % . ) What will be the uncertainty in its position?
A ( cdot 0.527 times 10^{10} mathrm{cm} )
B. ( 5.27 times 10^{9} mathrm{cm} )
c. ( 0.527 times 10^{-15} mathrm{cm} )
D. ( 0.527 times 10^{-9} mathrm{cm} )
11
1123said that cathode
rays consist of negatively charged particles and these were named as
electrons.
A . Goldstein
B. Thomson
D. Rutherford
11
1124From Bohr’s model radius of the orbit
and energy of the hydrogen atom are
calculated as:
This question has multiple correct options
A. radius of the 1st orbit is ( 0.529 A^{circ} )
B. energy of the 1st orbit is ( -13.6 e V )
C. energy of the 1st orbit is ( -21.72 times 10^{-19} mathrm{J} )
D. radius of the 1st orbit is ( 1.06 A^{circ} )
11
1125In which of the following process highest energy is absorbed?
( mathbf{A} cdot C u rightarrow C u^{+} )
в. ( B r rightarrow B r^{-} )
c. ( I rightarrow I^{-} )
D. ( L i rightarrow L i^{+} )
11
1126The threshold wavelength for ejection of an electron from metal is 310 nm. The
kinetic energy of emitted photoelectron is ( 36 times 10^{-20} J . ) Then the frequency of
incident light is:
A ( cdot 1.5 times 10^{15} mathrm{Hz} )
B . ( 2.5 times 10^{18} mathrm{Hz} )
c. ( 1 times 10^{22} H z )
D. 2.5 ( times 10^{12} mathrm{Hz} )
11
1127The number of neutrons in the parent
nucleus which gives ( ^{14} mathrm{N} ) on beta emission is
11
112833. Hydrogen atoms are excited from ground state to the
state of principal quantum number 4. Then, the number
of spectral lines observed will be
(a) 3
(b) 6
(C) 5
(d) 2
11
1129The photoelectric effect of Ba consists of emission of electrons from its
ionisation energy on irradiation with light from the ionization energy of ( boldsymbol{H} e- ) atom is irradiation with light. A photon
with a minimum energy of ( 3.97 times )
( 10^{-19} J ) is necessary to eject electron
from Ba.
(a)What is the frequency of radiation corresponding to this value?
(b) Will a blue light of wavelength
( 450 n m ) be able to eject at electron from
Ba? (Given ( h=6.626 times 10^{-27} ) erg ( – )
( boldsymbol{s} boldsymbol{e} boldsymbol{c} )
( mathbf{A} cdot 6 times 10^{13} H z, ) yes
B. ( 6 times 10^{13} H z ), no
C ( .5 .99 times 10^{14} mathrm{Hz} ), yes
D. ( 3.6 times 10^{13} mathrm{Hz} ), no
11
1130When ( alpha ) -particles are sent through a
thin metal foil, most of them go straight through the foil because:
This question has multiple correct options
A. ( alpha ) – particles are much heavier than electrons
B. ( alpha ) -particles are positively charged
c. most part of the atom is empty space
D. ( alpha ) -particles move with high speed
11
1131Suppose the elements ( X ) and ( Y )
combine to form two compounds ( boldsymbol{X} boldsymbol{Y}_{2} )
and ( X_{3} Y_{2} . ) When 0.1 mole of ( X Y_{2} )
weighs ( 10 g ) and 0.05 mole of ( X_{3} Y_{2} )
weighs ( 9 g ), the atomic weights of ( X ) and
( boldsymbol{Y} ) are:
11
113226. The radius of the Bohr orbit in the ground state of hydrogen
atom is 0.5 Å. The radius of the orbit of the electron in
the third excited state of He will be
(a) 8 Å
(b) 4 Å
(c) 0.5 Å
(d) 0.25 Å
11
1133What is the name and symbol of the element with atomic number ( 112 ? )
A. Ununbium, Uub
B. Unnilbium, Unb
c. Ununnillum, uun
D. Ununtrium, Uut
11
1134Q. 23 Show the distribution of electrons in oxygen atom (atomic number 8)
using orbital diagram.
Ans.
O = 15² 282 204
11
113519. The emission spectra is observed by the consequence of
transition of electron from higher energy state to ground
state of Het ion. Six different photons are observed
during the emission spectra, then what will be minimum
wavelength during transition?
(a)
27 RH
(b) 15 RH
15
16
(c) 16RA
15R,
11
1136An electron is moving in 4 th orbit and its de-Broglie wavelength is ( lambda ). What is the circumference of the fourth orbit?
( A cdot 2 / lambda )
B. ( 2 lambda )
c. ( 4 lambda )
D. ( 4 / lambda )
11
1137From equaliomu
n atom corresponding to
ie. E< E p < Ec. If a
liations corresponding to the
11. Energy levels A, B, C of a certain atom corres
increasing values of energy i.e. EA <ER <E
are the wavelengths of radiations correspondin
transitions C to B, B to A and C to A, respective
of the following statements is correct
atom is
drogen
e atom
(2) Az = 2 + 2
(6) dez-
hth
(d) z = x + 22
(c) , + 2y + 2z = 0
a
11
.
1
m
11
1138ULI 2
U
10 ULULLLEE 39
Q43. An ion with mass number 37 possesses one unit of negative charge. If
imber 37 possesses one unit of negative charge. If the ion contains 11.1%
more neutrons than the electrons, find the symbol of the ion.
2
11
1139Total no. of electron in ( N a ) having ( n times )
( ell=0 ) is :
( mathbf{A} cdot mathbf{5} )
B. 2
( c cdot 6 )
D. 8
11
1140What is the name for the number of
protons in an atom?
A. Atomic identity
B. Atomic mass
c. Atomic weight
D. Atomic number
11
1141The discovery of proved that
atom is divisible.
11
114241. A stationary hydrogen atom of mass M emits a photon
corresponding to the first line of Lyman series. If R is the
Rydberg’s constant, the velocity that the atom acquires is
3 Rh
Rh
4 M
4M
(c) Rh
an
(d) Rh
11
1143What would be the minimum
uncertainty in de-Broglie wavelength of a moving electron accelerated by potential difference of 6 volt and whose uncertainty in position is ( frac{7}{22} n m ? )
A ( .6 .25 AA )
в. 6 А
c. 0.625 ,
D. ( 0.3125 dot{A} )
11
114469. If potential energy between a proton and an electron is
given by TU1 = ke’/2R”, where e is the charge of electron
and R is the radius of atom, then radius of Bohr’s orbit is
given by (h = Planck’s constant, k = constant)
ke²m
60² ke²m
4x² ke²m
2n ke²m
n n
11
1145What is the ratio between the energies
of two radiations one with a wavelength of ( 6000 A ) and other with 2000 A?
11
1146Q.46 Match the following.
Column 1
A. Photon
B. Electron
N-
Column II
1. Value is 4 for N-shell
2. Probability density
3. Always positive value
4. Exhibits both momentum
and wavelength
w
D. Principal quantum
number n
11
1147The predominant yellow line in the spectrum of a sodium vapour lamp has a wavelength of 590nm. What minimum accelerated potential is needed to excite this line in an electron
tube having sodium vapours?
A. 8.44 volt.
B . 2.11 volt.
c. 6.11 volt.
D. 4.22 volt.
11
1148The outermost electronic configuration of the most electronegative element is:
( mathbf{A} cdot n s^{2} n p^{3} )
В ( cdot n s^{2} n p^{4} )
c. ( n s^{2} n p^{5} )
D. ( n s^{2} n p^{6} )
11
1149An atom of an element has one electron
in the valence shell and the two inner
shells have 8 electrons each. Find the
atomic number of that element.
11
1150The ratio of the radii of the atom to
the nucleus is :
A ( cdot 10^{4}: 1 )
B . ( 10^{-4}: 1 )
( mathrm{c} cdot 10^{2}: 1 )
D. ( 10^{3}: 1 )
11
1151Energy of the state ( S_{1} ) in units of the hydrogen atom ground state energy is:
A. 0.75
B. 1.50
c. 2.25
D. 4.50
11
1152How many maximum electrons ( f )
subshell can accommodate?
A . 12
B. 14
( c cdot 8 )
D. 10
11
1153The maximum tendency to form unipositive ion is for the element which has the following electronic configuration:
A ( cdot 1 s^{2}, 2 s^{2}, 2 p^{6}, 3 s^{2} )
B . ( 1 s^{2}, 2 s^{2}, 2 p^{6}, 3 s^{2}, 3 p^{1} )
c. ( 1 s^{2}, 2 s^{2}, 2 p^{6} )
D. ( 1 s^{2}, 2 s^{2}, 2 p^{6}, 3 s^{2}, 3 p^{3} )
11
115413. The electron in a hydrogen atom makes a transition from
an excited state to the ground state. Which of the following
statements is true
(a) Its kinetic energy increases and its potential and total
energies decrease
(b) Its kinetic energy decreases, potential energy increases
and its total energy remains the same
(c) Its kinetic and total energies decrease and its potential
energy increases
(d) Its kinetic, potential and total energies decreases
11
1155The experiment which led to the discovery of nucleus was performed by :
A. Goldstein
B. J.J. Thomson
c. Dalton
D. Rutherford
11
1156A proton and an ( alpha ) -particle are accelerated through the same potential difference. The ratio of their De Broglie
wavelength is:
A. ( sqrt{2} )
B. ( frac{1}{sqrt{2}} )
( c cdot 2 sqrt{2} )
D. 2
11
1157In a certain electronic transition in the
hydrogen atom from an initial state (1) to a final state (2), the difference in the
orbital radius ( left(r_{1}-r_{2}right) ) is 24 times the
first Bohr radius. Identify the transition:
( mathbf{A} cdot 5 rightarrow 1 )
B . ( 25 rightarrow 1 )
c. ( 8 rightarrow 3 )
D. ( 1 rightarrow 5 )
11
1158Which of the following is(are) matter?
Chair, air, love, smell, hate, almonds, thought, cold, cold-drink, smell of
perfume.
11
1159What is the hybridization state of
carbon number 2 and 3 in the following
compound ( boldsymbol{C H}_{2}=boldsymbol{C H}-boldsymbol{C} equiv boldsymbol{C H} )
A. sp and ( s p^{2} )
B. ( s p^{2} ) and ( s p )
( mathbf{c} cdot s p^{3} ) and ( s p )
D. ( s p ) and ( s p )
11
1160К) Тоос сороо
28. A metal surface is illuminated by a light of given intensity
and frequency to cause photoemission. If the intensity of
illumination is reduced to one-fourth of its original value,
then the maximum KE of emitted photoelectrons will become
(a) (1/16)th of original value
(b) unchanged
(c) twice the original value
(d) four times the original value
11
1161Which of the following arrangements of electrons is mostly likely to be stable?
( A )
begin{tabular}{|c|c|c|c|c|c|}
hline( uparrow ) & ( uparrow ) & ( uparrow d ) & ( uparrow ) & ( uparrow ) & ( ^{4 s} ) \
hline
end{tabular}
в. begin{tabular}{|c|c|c|c|c|c|}
hline( uparrow downarrow ) & ( uparrow ) & ( uparrow ) & ( uparrow ) & ( uparrow ) & ( uparrow ) \
hline
end{tabular}
( c )
begin{tabular}{|c|c|c|c|c|}
hline( uparrow ) & ( uparrow ) & ( uparrow ) & ( uparrow ) & ( uparrow ) \
hline
end{tabular} ( frac{4}{downarrow} )
D. begin{tabular}{r}
( 4 s ) \
hline( uparrow uparrow )
end{tabular} begin{tabular}{|c|c|c|c|c|c|}
hline( uparrow ) & ( uparrow ) & ( uparrow ) & ( uparrow ) & ( uparrow ) \
hline
end{tabular}
11
1162The electrons are filled in various sub
levels according to the order of their energies, is known as:
A. Aufbau principle
B. Pauli’s principle
c. Hund’s rule
D. ( n l^{x} ) principle
11
1163What is the degeneracy of the level of ( boldsymbol{H} )
-atom that has energy ( left(-frac{R_{H}}{9}right) ? )
A . 16
B. 9
( c cdot 4 )
( D )
11
1164Assertion
Isotopes of a particular element have nearly identical chemical behaviour.
Reason
They have identical electron
configuration.
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
11
1165In nodal plane probability of finding an electron is:
A . zero
B. one
c. maximum
D. none of the these
11
1166Assertion
The nucleus of gold is stable even though there is a very strong coulombic
repulsion among the protons.
Reason
The inverse square coulomb force is exactly balanced by another inverse square force which is very powerful than nuclear force.
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
11
1167Assertion
Threshold frequency is a characteristic
for a metal.
Reason
Threshold frequency is a maximum frequency required for the ejection of electron from the metal 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. Assertion is incorrect but Reason is correct
11
1168Q. 8 The period number in the long form of the periodic table is equal to
(a) magnetic quantum number of any element of the period
(b) atomic number of any element of the period
o s (c) maximum principal quantum number of any element of the period
1993 (d) maximum azimuthal quantum number of any element of the period
11
1169The number of sub-energy levels in any energy level is given by:
( A cdot n )
B. ( l )
( c cdot m )
D.
11
1170Assertion
( beta ) -particles are deflected less than ( alpha ) particles in electrical field.
Reason
( beta ) -particles have very low mass.
A. ( A ) is correct but ( R ) is wrong
B. ( A ) is wrong but ( R ) is correct
c. Both ( A ) and ( R ) are correct and ( R ) is correct explanation of ( A )
D. Both ( A ) and ( R ) are correct but ( R ) is not correct explanation of ( A )
11
1171Rutherford’s atomic model does not
obey:
B. maxwell theory of electrodynamics
c. newton’s law
D. none of these
11
1172Among the following groups which represents the collection of isoelectronic species?
A ( cdot N O^{+}, C_{2}^{2-}, O_{2}^{-}, C O )
в. ( N_{2}, C_{2}^{2-}, C O_{2}^{-}, N O )
c. ( C O, N O^{+}, C N^{-}, C_{2}^{2} )
D. ( N O, C N^{-}, N_{2}, O_{2}^{-} )
11
1173The number of protons in an ion from which ( (Z-1) ) electrons are removed
having its ionization energy ( 11800 k J )
( m o l^{-1} ) is :
A. three
B. five
c. four
D. insufficient information
11
1174Assertion
( 35 C l ) and ( _{17}^{37} C l ) have the same chemical
( 17^{7} )
properties.
Reason
Isotopes have the same number of
protons and electrons and the same
chemical reactions.
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
11
1175Thomson’s model could not explain the :
A. stability of an atom
B. position of nucleus in an atom
c. scattering of alpha particles
D. all of above
11
1176What will the ratio of the wavelength of
the first line to that of the second line of
Paschen series of H atom?
A .256: 175
B. 175: 256
c. 15: 16
D. 24: 27
11
1177For Balmer series in the spectrum of
hydrogen, the wave number of each line is given by ( overline{boldsymbol{v}}=boldsymbol{R}_{boldsymbol{H}}left[frac{mathbf{1}}{boldsymbol{n}_{mathbf{1}}^{2}}-frac{mathbf{1}}{boldsymbol{n}_{2}^{2}}right] ) where ( boldsymbol{R}_{boldsymbol{H}} ) is
constant and ( n_{1}, n_{2} ) are integers, which of the following statements is (are)
correct?
1. As wavelength decreases, the lines in the series converge.
2. The integer ( n_{1} ) is equal to 2
3. The ionization energy of hydrogen can be calculated from the wave number of
these lines.
4. The lines of longest wavelength
corresponds to ( n_{2}=3 )
( A cdot 1,2 ) and 3
B. 2, 3 and 4
( mathbf{c} cdot 1,2 ) and 4
D. 2 and 4
E. 2 only
11
1178The maximum number of dectrons in
( Z n ) is :
A . 10
B. 0
( c cdot 2 )
D. 6
11
1179(A) Energy emitted in the transition
( (5 rightarrow 2) ) is less than that of ( . ) the
transition ( (2 rightarrow 1) ) in all hydrogen like
atoms.
(R) The energy difference between 1st
and 2 nd shell is greater than that of any two energy levels provided level (1) is not part of those two energy levels.
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
11
1180Argon has three isotopes with relative atomic masses of 36,38 and ( 40 . ) Given that the average relative atomic mass of naturally occurring argon is 39.95 Which of the following statements must
be correct?
A. 40 Ar is less abundant than ( ^{38} ) Ar
B. ( 40 mathrm{Ar} ) is more abundant than either ( ^{36} mathrm{Ar} ) or ( ^{38} mathrm{Ar} )
C. ( 40 mathrm{Ar},^{38} mathrm{Ar} ) and ( ^{36} mathrm{Ar} ) are equally abundant
D. ( 36 A r ) is more abundant than ( ^{40} A r )
11
1181The total energy of the electron in any orbit of one electron containing species is given by the expression:
A ( cdot-e^{2} / r^{2} )
B . ( -n^{2} h^{2} / 2 pi^{2} Z^{2} e^{4} m )
c. ( -2 pi^{2} m Z^{2} e^{4} / n^{2} h^{2} )
D. ( n h / 2 pi )
11
1182Describe Bohrs model of the atom11
1183On the basis of composition, which of the following is a type of matter?
A. Compound
B. Solid
c. Liquid
D. Both b and c
11
1184In which of the following autfnau principle is violated?
( A )
( frac{uparrow}{2 s} ) begin{tabular}{c|c|c}
hline( uparrow downarrow ) & ( uparrow ) & ( uparrow ) \
hline ( mathbf{2 p} ) & & \
hline
end{tabular}
B. ( frac{sqrt{1} downarrow}{2 s} )
( c )
( uparrow downarrow ) begin{tabular}{c|c|c|}
hline( uparrow ) & ( uparrow ) & ( uparrow ) \
hline ( 2 p ) & & \
hline
end{tabular} ( 2 mathrm{s} )
( D )
( frac{sqrt{1} mid}{2 s} ) begin{tabular}{c|c|c|c|c|}
hline( uparrow downarrow ) & ( uparrow ) & ( uparrow ) \
hline ( 2 p ) & & & \
hline
end{tabular}
11
118573. The minimum kinetic energy required for ionization of
a hydrogen atom is E, in case electron is collided with
hydrogen atom. It is E, if the hydrogen ion is collided and
E, when helium ion is collided. Then,
(a) E, = E2 = E (b) E, > E> E
(c) E; E, > E2
11
118619.7 kg of gold was recovered from a smuggler. The atoms of gold recovered
are:
A. 100
B. ( 6.02 times 10^{23} )
c. ( 6.02 times 10^{24} )
D. ( 6.02 times 10^{25} )
11
1187Q. 16 If travelling at same speeds, which of the following matter waves have
the shortest wavelength?
(a) Electron
(b) Alpha particle (He2+)
(c) Neutron
(d) Proton
11
1188Which of the following sets of quantum numbers is correct for an electron in ( 4 f )
orbital?
( A cdot n=4,1=3, m=+4, s=+frac{1}{2} )
B. ( n=4,1=4, m=-4, s=+frac{1}{2} )
( c cdot n=4,1=3, m=+1, s=+frac{1}{2} )
D. ( n=4,1=2, m=2, s=+frac{1}{2} )
11
1189The mass number of ( X ) is 23 which
contains 15 electrons. What is the
atomic mass of ( boldsymbol{X} ) ?
A . 38 amu
B. 23 amu
c. 18 amu
D. None of above
11
1190Assertion
The mass number of hydrogen is equal
to its atomic number.
Reason
H-atom has no neutrons.
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.
11
1191A radioactive element decays by ( beta )
emission. If the mass of parent and
daughter nuclide are ( m_{1} ) and ( m_{2} )
respectively, the energy liberated during the emission is :
A. ( left[m_{1}-m_{2}-2 m_{e}right] c^{2} )
в. ( left[m_{1}-m_{4}-2 m_{e}right] c^{1} )
c. ( left[m_{1}-m_{1}-3 m_{e}right] c^{3} )
D. None of these
11
1192According to the Bohr Theory, which of the following transitions in the hydrogen atom will give rise to the least energetic photon?
A ( n=5 ) to ( n=3 )
3
в. ( n=6 ) to ( n=1 )
c. ( n=5 ) to ( n=4 )
D. ( n=6 ) to ( n=5 )
11
1193From the following find out groups of isotopes, isobars and isotones:
( _{8}^{16} boldsymbol{O}_{, 19}^{39} boldsymbol{K}_{, 6}^{14} boldsymbol{C}_{, 92}^{239} boldsymbol{U}_{, 7}^{14} boldsymbol{N}_{, 20}^{40} boldsymbol{C} boldsymbol{a}_{, 92}^{238} boldsymbol{U}_{, 32}^{77} boldsymbol{G} )
11
1194Which of the following statement is
false regarding isotopes?
A. They are atoms of same element having same number of protons and electrons but different number of neutrons.
B. Isotopes of an element have similar chemical perperties but different physical properties.
C. All the isotopes of an element have same number of valence electrons
D. The three isotopes of hydrogen (Protium, Deuterium and Tritium) contains one, two and three neutrons respectively.
11
1195Consider Bohr theory for hydrogen atom. The magnitude of angular momentum, orbit radius and velocity of the electron
in ( n^{t h} ) energy state in a hydrogen atom are ( l, r ) and ( v ) respectively. Find out the
value of ( x ) if product of ( v, r ) and ( l ) is
directly proportional to ( n^{x} )
11
119612. In a hydrogen-like atom an electron makes transition
from an energy level with quantum number n to another
with quantum number (n-1). If n >> 1. the frequency of
(a)
(b)-
(JEE Main 2015)
11
1197In order for an electron to move from the
second energy level (n=2) to the fourth energy level ( (n=4) ) the atom needs to:
A. release heat
B. release a photon
C. maintain a constant energy
D. release energy.
E. absorb energy.
11
1198What determines the size of
isoelectronic species?
A. Valence
B. Nuclear charge
c. lonization potential
D. None of these
11
1199Isotopes are those atoms which have
same :
A. atomic number
B. atomic mass
C. atomic charge
D. all
11
1200If the speed of electrons in Bohr’s first
obtain of hydrogen is ( ^{prime} X^{prime} ) the speed of
electrons in third orbit is:
( A cdot frac{X}{9} )
в. ( frac{x}{3} )
( c .3 x )
D. 9.8
11
1201Assertion
Nuclide ( _{13}^{30} A l ) is less stable than ( _{20}^{40} C a )
Reason

Nuclide having odd number of protons and neutrons are generally unstable.
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

11
1202Olle, 11,
TWO,
U
TU.
Q28.
2
(i) An atomic orbital has n = 3. What are the possible values of I and m,?
(ii) List the quantum numbers (m, and I) of electron for 3d orbital.
(iii) Which of the following orbitals are possible?
1p, 2s, 2p and 3f.
11
12034. The de Broglie wavelength associated with a ball of
mass 1 kg having kinetic energy 0.5 J is:
(a) 6.626 x 10-34 m (b) 13.20 x 10-34 m
(c) 10.38 x 10-21 m (d) 6.626 10-34 Å
11
1204( begin{array}{ll}text { List – I } & text { List – II } \ text { I) } Psi^{2} text { depends only upon distance } & begin{array}{l}text { a) } p- \ text { orbitals }end{array} \ begin{array}{l}text { 11) } Psi^{2} text { depends upon distance and on } \ text { one direction }end{array} & begin{array}{l}text { b) } mathrm{d}- \ text { orbital }end{array} \ begin{array}{l}text { III) } Psi^{2} text { depends upon distance and on } \ text { two directions }end{array} & begin{array}{l}text { c) } mathrm{f} text { – } \ text { orbital }end{array} \ begin{array}{l}text { IV) } Psi^{2} text { depends upon distance and on } \ text { three directions }end{array} & begin{array}{l}text { d) } mathrm{s} text { – } \ text { orbitals }end{array}end{array} )
( A cdot|-d,| I-c,|I|-b, mid V-a )
B. ( |-c,||-b,|||-a, mid V-d )
C. ( |-d,| I-a,|I|-b, mid V-c )
D. I-d, II-a, III-c, IV-b
11
1205Write the general outer electronic
configuration of ( s-, p-, d- ) and ( f- ) block elements.
11
120655. In X-ray tube, when the accelerating voltage Vis halved,
the difference between the wavelength of K, line and
minimum wavelength of continuous X-ray spectrum
(a) remains constant
(b) becomes more than two times
(c) becomes half
(d) becomes less than two times
11
120756. X-rays emitted from a copper target and a molybdenum
target are found to contain a line of wavelength 22.85 nm
attributed to the K, line of an impurity element. The K.
lines of copper (Z = 29) and molybdenum (Z = 42) have
wavelengths 15.42 nm and 7.12 nm, respectively. The
atomic number of the impurity element is
(a) 22
(b) 23
(c) 24
(d) 25
11
1208(i) Calculate the number of electrons
which will together weighs one gram.
(ii) Calculate the mass and charge of
one mole of electrons.
11
1209A baseball of mass ( 200 mathrm{g} ) is moving with velocity ( 30 times 10^{2} mathrm{cm} / mathrm{s} ). If we can locate
the baseball with an error equal in
magnitude to the ( lambda ) of the light used ( mathbf{5 0 0 0} boldsymbol{A} ), then the uncertainty in
momentum compared with the total momentum of base ball is:
A ( .1 .75 times 10^{-29} )
В. ( 1.34 times 10^{-29} )
c. ( 1.89 times 10^{-29} )
D. ( 2.03 times 10^{-29} )
11
121003. Which orbital is non-directional ?
Ans Sorbital
11
1211Multiple Answer Question Bohr’s model could not explain the
spectra:
This question has multiple correct options
A. of electron species having more than one electron
B. in the presence of magnetic field
c. of metal atoms
D. in the presence of electric field
11
1212Similar to electron diffraction, neutron
diffraction microscope is also used for the determination of the structure of
molecules. If the wavelength used here
is ( 800 mathrm{pm} ), calculate the characteristic velocity associated with the neutron.
11
1213Some hydrogen-like atom in ground state absorb ( n ) photons having the same energy and on de-excitation, it
emits exactly ( n ) photons. Then the energy of absorbed photon may be:
This question has multiple correct options
A. ( 91.8 e V )
B. ( 40.8 e V )
c. ( 48.4 e V )
D. ( 54.4 e V )
11
1214For which of the following species sum
spin quantum number of all electrons
comes out to be zero?
A ( cdot C r^{+}(Z=24) )
в. ( operatorname{Sc}(Z=21) )
c. ( C r^{+}(Z=29) )
D. ( N a(Z=11) )
11
1215Which among the following is incorrect
of ( _{5} B ) in normal state?
A. begin{tabular}{|c|c|c|c|c|}
hline ( 2 s ) & ( 2 p ) & & \
hline( uparrow uparrow ) & & ( uparrow ) & \
hline
end{tabular}
B. begin{tabular}{|c|c|c|c|c|}
hline ( 2 s ) & multicolumn{3}{|c|} {( 2 p )} \
hline( uparrow ) & ( uparrow ) & ( uparrow ) & multicolumn{2}{|c|} { Against aufbau principle as well as Hund’s rule } \
hline
end{tabular}
( c )
begin{tabular}{c|c|c|c|}
( 2 s ) & multicolumn{2}{c} {( 2 p )} \
hline( uparrow uparrow ) & ( uparrow ) & & \
hline
end{tabular} Violation of Pauli’s exclusion
principle and not Hund’s rule
D. ( 2 p ) ( 2 s ) ( uparrow downarrow ) ( : quad ) Against aufbau principle
11
1216When an ( alpha ) -particle is
emitted
A. element moves 2 places to the right in the periodic table
B. element moves one place to the left
C. element moves 2 places to the left in the periodic table
D. elements maintains its position
11
1217Which transition corresponds to series
limits for paschen series?
11
1218One proton weighs more than:
A . 1,800 electrons
B. 1,800 neutrons
c. Above both options are correct
D. None of the above
11
1219Q21. When is the energy of electron regarded as zero?11
1220The frequency of light emitted for the
transition ( n=4 ) to ( n=2 ) of ( H e^{+} ) is
equal to the transition in ( mathrm{H} ) atom
corresponding to which of the following?
A ( . n=3 ) to ( n=1 )
в. ( n=2 ) to ( n=1 )
c. ( n=3 ) to ( n=2 )
D. ( n=4 ) to ( n=3 )
11
1221An element with atomic number 117 is
known as:
A. nihonium
B. flerovium
c. tennessine
D. roentgenium
11
1222Rutherford’s alpha Scattering
experiment showed that:
A. the atoms were smashed up by alpha particles
B. the atoms consisted or protons in a matrix of electrons
C. the nucleus was quite large and was positively charged
D. the nucleus was very small and positively charged
11
1223Determine the number of electron in the isotope of ‘H’ (mass no. 2).
( mathbf{A} cdot mathbf{1} )
B. 2
( c cdot 0 )
D.
11
1224An ( alpha ) – particle of ( mathrm{KE} mathbf{5 . 4} M e V ) is projected towards ( C r ) – nucleus ( (Z= )
24). What is its distance of closest
approach? ( left(e=1.6 times 10^{-19} Cright) )
11
1225The potential energies of first, second
and third Bohr’s orbits of ( H e^{+} ) cation
are ( E_{1}, E_{2} ) and ( E_{3} . ) The correct sequence
of these energies is:
A ( . E_{1}>E_{2}>E_{3} )
B . ( E_{1}=E_{2}>E_{3} )
c. ( E_{1}=E_{2}=E_{3} )
D. ( E_{3}>E_{2}>E_{1} )
11
1226Value of all quantum number for 4 th
electron of ( left(_{16} Sright) )
11
1227The number of times by which an electron is lighter than a hydrogen
atom:
A . 1840
в. 1837
( c .1836 )
D. none of the above
11
1228Name the compounds used in preparation of nylon-66.
A. E-caprolactum
C. Dimethyl tetraphthalate
D. Hexamethylene diamine
11
1229In a sample, electronjumps from ( 5^{t h} ) excited state to ground state then number of spectral lines in visible
range will be:
A . 4
B. 3
c. 2
( D )
11
1230Among the following, the isoelectronic species is/ are:
(i) ( boldsymbol{O}^{2-}, boldsymbol{F}^{-}, boldsymbol{N} boldsymbol{a}^{+}, boldsymbol{M} boldsymbol{g}^{2+} )
( (text { ii }) N a^{+}, M g^{+}, A l^{3+}, F^{-} )
(iii) ( N^{3-}, O^{2-}, F^{-}, N e )
( A cdot ) (i) and (ii)
B. (i), (ii) and (iii)
c. (ii) and (iii)
D. (i) and (iii)
11
1231Isotope per Natural abundance
[
begin{array}{ll}
^{1} boldsymbol{H} & mathbf{9 9 . 9 8 5} \
^{2} boldsymbol{H} & mathbf{0 . 0 1 5}
end{array}
]
The average atomic mass of hydrogen using the following data is
11
1232Quantum theory was postulated by:
A. Rutherford
B. Maxwell
c. Max Planck
D. Becquerel
11
1233What are isoelectronic spices? give example?11
1234A small particle of mass ( m ) moves in such a way that ( P . E=-frac{1}{2} m k r^{2}, ) where
( k ) is a constant and ( r ) is the distance of
the particle from origin. Assuming Bohr’s model of quantization of angular momentum and circular orbit, ( r ) is
directly proportional to:
( mathbf{A} cdot n^{2} )
в.
c. ( sqrt{n} )
D. none of these
11
1235Based on equation ( boldsymbol{E}=mathbf{2 . 1 7 8} times mathbf{1 0}^{mathbf{1 8}} mathbf{J} )
( left(frac{Z^{2}}{n^{2}}right), ) certain conclusions are written Which of them is not correct?
A. The negative sign in equation simply means that the energy of electron bound to the nucleus is lower than i would be if the electrons were at the infinite distance from the nucleus
B. Larger the value of n, the larger is the orbit radius
c. Equation can be used to calculate the change in energy when the electron changes orbit
D. For ( n=1 ), the electron has a more negative energy that it does for ( n=6 ) which means that the electron is more loosely bound in the smallest allowed orbit
11
1236The minimum possible angular momenturn of an election present in an orbital is ( ldots ldots . . . . . . ) if the magnetic quanthem number associated with this
orbinal are -1,0,+1
A ( cdot frac{5 h}{2 pi} )
в. ( frac{3 h}{2 pi} )
( c cdot frac{h}{2 pi} )
D. ( frac{h}{pi} )
11
1237( ^{87} ) Rb undergoes ( beta ) -decay ( left(t_{1 / 2}=4.7 timesright. ) ( left.10^{10} text { year }right) ) to form ( ^{87} ) Sr. An analysis of
the rock sample shows relative number of ( ^{87} mathrm{Sr} ) and ( ^{87} ) Rb atoms ( 0.052: 1 . ) If all
the ( ^{87} mathrm{Sr} ) is formed from ( beta ) -decay of ( ^{87} mathrm{Rb} )
The age of the rock is :
A . ( left[2.21 times 10^{9} text { year }right] )
B . ( left[3.43 times 10^{9} text { year }right] )
C . ( left[4.13 times 10^{9} text { year }right] )
D. none of these
11
1238Velocity of de Broglie wave is given by:
( ^{A} cdot frac{c^{2}}{v} )
в. ( frac{h v}{m c} )
( c cdot frac{m c^{2}}{h} )
D. ( v lambda )
11
1239An absorption of ( 12.088 e V ) energy by an
electron in ground state of ( boldsymbol{H} ) -atom brings in the excitation of electron to which orbit?
A. Two
B. Three
c. Four
D. Not possible. Minimum ene ( 6 e^{v} )
11
1240State True or False.
High pressure and low voltage should be maintained in the discharge tube for the production of cathode rays.
A . True
B. False
11
1241Presence of electrons is shown by three
dimensional shape of orbit with:
A. high probability
B. low probability
c. no probability
D. slow ratio
11
1242Arrangement of the following group of orbitals in which they fill with electrons
( (5 f, 6 p, 4 p, 6 s, 4 d, 4 f) )
( mathbf{A} cdot 4 p, 4 d, 6 s, 4 f, 6 p, 5 f )
B. ( 6 s, 4 d, 4 f, 5 f, 4 p, 6 p )
( mathbf{c} .6 s, 4 p, 4 d, 4 f, 5 f, 6 p )
D. ( 4 d, 4 p, 4 f, 5 f, 6 s, 6 p )
11
1243Give the electronic configurations of the following:
a. ( H^{-} ) b. ( mathrm{He}^{+} ) c.F ( ^{-} ) d. ( mathrm{N}^{2+} )
t
11
1244Splitting of spectral lines in the presence of electric field is known as:
A. Stark effect
B. Zeeman’s effect
c. compton effect
D. Moseley’s effect
11
1245Proton was discovered by:
A. Thomson
B. Rutherford
D. Goldstein
11
1246Most of the alpha particles go straight through the foil if it is passed through a thin metal foil. This is due to the reason
that:
A. alpha particles are much heavier than electrons
B. alpha particles are positively charged
c. most part of the atom is empty
D. alpha particles move with the high velocity
11
1247What are the limitations of Rutherford’s
model of the atom?
11
1248The velocity of an ( e^{-} ) in excited state of
H-atom is ( 1.093 times 10^{6} ) m/s. What is the
circumference of this orbit?
A ( cdot 3.32 times 10^{-10} mathrm{m} )
В. ( 6.64 times 10^{-10} mathrm{m} )
c. ( 13.30 times 10^{-10} mathrm{m} )
D. ( 13.28 times 10^{-8} mathrm{m} )
11
1249The number of electrons, protons and
neutrons in an atom whose atomic
number is 11 and mass number 23 will
be:
A. 11,11,12
B. 11,12,11
c. 12,11,11
D. 23,11,23
11
1250Explain the reason for exceptional electroic congiguration of copper and chromium.11
1251( 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{6} 4 s^{2} )
The given electronic configuration is
for:
A . Na
B. Fe
c. ( C l^{-} )
D. Rb
E ( . C a^{+} )
11
1252The maximum of electrons in ( mathrm{H} ) atom
that will emit maximum energy is :
( A cdot n_{3} rightarrow n_{1} )
в. ( n_{4} rightarrow n_{3} )
( mathrm{c} cdot mathrm{n}_{5} rightarrow mathrm{n}_{4} )
( mathrm{D} cdot mathrm{n}_{6} rightarrow mathrm{n}_{5} )
11
1253Calculate the wavelength and energy of radiation emitted for the electronic
transition from infinity to stationary state of the hydrogen.
B. 3.142 ( times 10^{18} ) 」
C . ( 1.021 times 10^{18} mathrm{J} )
D . 0.536 ( times 10^{18} ) 」
11
1254Statement 1: Two isotopes of the same
element have the same mass number
Statement 2: Isotopes have the same number of protons.
A. Both Statement 1 and Statement 2 are correct and
Statement 2 is the correct explanation of Statement 1
B. Both Statement 1 and Statement 2 are correct and
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.
E. Both Statement 1 and Statement 2 are not correct.
11
1255The e/m ratio for cathode rays:
A. is constant
B. varies as the atomic number of the element forming the cathode in the discharge tube changes
C. varies as the atomic number of the gas in the discharge tube varies
D. has the smallest value when the discharge tube is filled with hydrogen
11
1256The wavelength of first line of Balmer
spectrum of hydrogen will be:
в. ( 4101 hat{A} )
( c .6569 hat{A} )
D. ( 4861 A )
11
1257The energy of the first orbit of ( boldsymbol{H} boldsymbol{e}^{+} ) is ( -871.6 times 10^{-20} J . ) The energy of the
electron in the first orbit of hydrogen would be:
( begin{array}{lll}text { A. }-871.6 times & 10^{-20} Jend{array} )
B . ( -435.8 times quad 10^{-20} J )
( begin{array}{lll}text { C. }-217.9 times & 10^{-20} Jend{array} )
begin{tabular}{ll}
D. ( -108.9 times ) & ( 10^{-20} mathrm{J} ) \
hline
end{tabular}
11
1258The subatomic particle which remains unchanged during the chemical reaction is/are

This question has multiple correct options
A. proton
B. electron
c. neutron
D. All of the above

11
1259When a certain metal is irradiated with
a radiation of frequency ( 3.2 times 10^{16} S^{-1} ) the photo electrons emitted had twice the kinetic energy as did the phototelectrons emitted when the same
frequency ( 2 times 10^{16} S^{-1} . ) Calculate
threshold frequency of metal.
11
1260A neutral atom of an element has ( 2 mathrm{K}, 8 mathrm{L} )
( 9 mathrm{M} ) and ( 2 mathrm{N} ) electrons. The total number
of ( s ) electrons are:
( A cdot 8 )
B. 6
( c cdot 4 )
D. 10
11
1261Could aluminium foil serve the purpose
in ( alpha ) – ray scattering experiment. Explain the reason behind it.
11
1262Calculate the de Broglie wavelength for a beam of electron whose energy is ( mathbf{1 0 0} e V: )
( mathbf{A} cdot 1 A^{0} )
B . ( 1.23 A^{circ} )
c. ( 2.46 A^{circ} )
D. None of these
11
1263No.of nodal planes in ( 3 d ) -orbitals are :
( A cdot 2 )
B. 4
( c cdot 5 )
D. 10
11
1264The atomic number of an element is
determined by:
A. the number of electrons in one atom
B. the number of neutrons in one atom
c. the valency of the element
D. the number of protons in one atom
11
1265Which of the following was not explained by Bohr’s atomic model
A. Splitting of spectral lines in Magnetic field
B. Splitting of spectral lines in electric field
C. Bohr model could not explain the uncertainty principle of Heisenberg.
D. All of the above
11
1266According to J.J. Thomson’s atomic model, negative charges are embedded
in :
A. a lump of positive charge
B. lump of neutral charge
c. a lump of small atoms
D. nucleus
11
1267Isotopes are:
A. atoms of same element, having the different atomic number but same mass numbers
B. atoms of same element, having the same atomic number but different mass numbers
C. atoms of different elements with different atomic
numbers, which have the same mass number
D. atoms of different elements with same atomic numbers, which have different mass numbers
11
1268An electron in ( H ) -atom in ground state
absorbs 1.5 times as much energy as the minimum required for its escape (i.e., ( 13.6 e V) ) from the atom. Calculate
the wavelength of emitted electron.
A . ( lambda=4.70 times 10^{-10} mathrm{m} )
В. ( lambda=61 times 10^{-9} m )
c. ( lambda=4.70 times 10^{-14} mathrm{m} )
D. ( lambda=2.7 times 10^{-10} mathrm{m} )
11
1269In one average life:
A. half the radioactive nuclei decay
B. less than half the radioactive nuclei decay
C. more than half the radioactive nuclei decay
D. all the nuclei decay
11
1270Which is correct for any kind of
species?
( mathbf{A} cdotleft(E_{2}-E_{1}right)>left(E_{3}-E_{2}right)>left(E_{4}-E_{3}right) )
B ( cdotleft(E_{2}-E_{1}right)<left(E_{3}-E_{2}right)<left(E_{4}-E_{3}right) )
( mathbf{C} cdotleft(E_{2}-E_{1}right)=left(E_{3}-E_{2}right)=left(E_{4}-E_{3}right) )
D ( cdotleft(E_{2}-E_{1}right)=1 / 4left(E_{3}-E_{2}right)=1 / 9left(E_{4}-E_{3}right) )
11
1271Which of the following properties are similar for isotopes?
A. Physical properties
B. Chemical properties
c. Both physical and chemical properties
D. Neither physical nor chemical properties
11
127231. Magnetic field at the center (at nucleus) of the hydrogen-
like atoms (atomic number = z) due to the motion of
electron in nth orbit is proportional to
(b) n*
11
1273Given set of quantum numbers for a multi-electron atom is:
( boldsymbol{n} )
( l ) ( m ) ( s )
2
( begin{array}{cc}0 & 0end{array} ) ( +1 / 2 )
2
( -1 / 2 )
What is the next higher allowed set of ‘ ( n )
and ‘l’ quantum numbers for this atom
in the ground state?
A. ( n=2, l=0 )
В. ( n=2, l=1 )
c. ( n=3, l=0 )
D. ( n=3, l=1 )
11
1274A photon of wavelength ( 4 times 10^{-7} mathrm{m} )
strikes on the metal surface, the work
function of the metal is 2.13 eV.

Calculate the energy of the photon (eV)
(ii) the kinetic energy of the emission and (iii) the velocity of the photoelectrons ( (1 e V= ) ( left.1.6020 X 10^{-23} Jright) )

11
1275Which of the following orbit is impossible for an electron according to Bohr’s theory?
A ( cdot m v r=frac{h}{2 pi} )
B. ( m v r=frac{3 h}{4 pi} )
c. ( _{m v r}=frac{2 h}{pi} )
D. ( m v r=frac{4 h}{2 pi} )
11
1276What transition of ( L i^{+2} ) spectrum will
have same wavelength as that of
second line of Balmer series in ( boldsymbol{H} boldsymbol{e}^{+} )
spectrum?
11
1277Assertion
In an atom, the velocity of electron in
the higher orbits keeps on decreasing.
Reason
Velocity of electrons is inversely proportional to the radius of the orbit.
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
11
1278The atomic numbers of two elements A
and B are 11 and 12 respectively. Which element exhibits highest metallic property ? Write the molecular formula of the compounds formed when theses elements combine with the element ‘Z’
having atomic number 8
11
1279Which of the following statements are
correct?
This question has multiple correct options
A ( cdot ) The angular momentum of ( 3 p ) -orbital is ( frac{h}{sqrt{2} pi} )
B. The sixth electron of carbon atom has the quantum numbers ( n=2, ell=1, m=0, s=+frac{1}{2} ) or ( -frac{1}{2} )
C. Magnetic moment of ( V^{4+} ) ions is 1.73 BM ( (mathrm{V}=23) )
D. For azimuthal quantum number ( ell=3 ), the maximum
number of electrons is 6
11
1280Mass number is silghtly less than the actual atomic mass. Give reasons.11
1281The total energy emitted when electrons
of ( 1.0 mathrm{g} ) atom of hydrogen undergo transition giving the spectral line of lowest energy in the visible region of its atomic spectrum is:
( left[text { Given }: boldsymbol{E}_{mathbf{1}(boldsymbol{H})}=mathbf{2 . 1 7 6} times mathbf{1 0}^{-mathbf{1 8}}right] )
A . ( 1.82 times 10^{5} mathrm{J} / mathrm{mol} )
В. ( 1.96 times 10^{5} mathrm{J} / mathrm{mol} )
c. ( 2.01 times 10^{5} mathrm{J} / mathrm{mol} )
D. ( 2.06 times 10^{5} mathrm{J} / mathrm{mol} )
11
1282I: Gas-phase elements absorb or emit only specific wavelengths of visible light when excited by an electric
current.
Il: The energy levels that electrons can
occupy in gas-phase atoms and molecules are continuous.
11
1283The ( E_{1} ) of ( H ) is ( 13.6 e V . ) It is exposed to electromagnetic waves of ( 1028 dot{A} ) and gives out induced radiation. Find the

This question has multiple correct options
A ( cdot lambda_{3}=1216 hat{A} )
B . ( lambda_{2}=6568 AA )
c. ( lambda_{2}=1000 dot{A} )
D. ( lambda_{2}=2432 hat{h} )

11
1284The electron density of ( 3 d_{x y} ) orbital in ( Y Z ) plane is:
A . 50%
B. 95%
c. 33.33%
D. 0%
11
1285Q1.
(i) Calculate the number of electrons which will together weigh one gram.
(ii) Calculate the mass and charge of one mole of electrons.
11
1286The last member of ( 4 n+1 ) series is an
A. True
B. False
11
1287Assertion
During ( beta ) -decay, a new element with atomic number greater than one is
obtained.
Reason Protons and neutrons keep on changing
into one another through meson
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
11
1288The element used by Rutherford in his famous scattering experiment was
A. Gold
B. Tin
c. Silver
11
1289The electronic configuration ( 1 s^{2} 2 s^{2} 2 p x^{1} 2 p y^{1} 2 p z^{1} ) is of:
A.
B.
c. Na
D.
11
1290The graph between ( |Psi|^{2} ) and ( r( ) radial
distance) is shown below. This
represents:
A . 3s orbital
B. 1s orbital
c. 2p orbital
D. 2s orbital
11
1291Arrange the following in increasing energy levels:
( A cdot 5 p<4 d<3 p<4 f<5 d<6 s )
( B .3 p<4 d<5 p<6 s<4 )
( c cdot 3 p<4 d<5 p<4 f<6 s )
D. ( 3 p<4 d<5 p<4 f<6 p )
11
1292How many unbonded pairs of electrons are found in a neutral atom of sulfur?
A. Three
B. Two
c. one
D. None
11
1293In Bohr series of lines of hydrogen
spectrum, the third line from the red
end corresponds to which one of the following inter – orbit jumps of the electron for Bohr orbits in an atom of
hydrogen ?
( mathbf{A} cdot 3 rightarrow 1 )
B . ( 5 rightarrow 2 )
c. ( 2 rightarrow 5 )
D. ( 3 rightarrow 2 )
11
1294Compared to the mass of lightest nucleus the mass of an electron is only:
A ( cdot frac{1}{80} )
B . ( frac{1}{360} )
( c cdot frac{1}{1800} )
D. ( frac{1}{1000} )
11
1295The energy required to melt 1 g ice is ( 33 J . ) The number of quanta of radiation
of frequency ( 4.67 times 10^{13} ) sec ( ^{-1} ) that
must be absorbed to melt ( 10 mathrm{g} ) ice is:
A ( cdot 1.065 times 10^{22} )
B. ( 3.205 times 10^{23} )
c. ( 9.076 times 10^{20} )
D. none of the above
11
1296Atomic number of calcium is ?
( A cdot 18 )
B. 19
c. 20
D. 21
11
1297Na
AL
13. From the figure describing photoelectric effect, we may
infer correctly that
(a) Na and Al both have
the same threshold
frequency
(b) Maximum kinetic
energy for both the
Ro Re
metals depend linearly
10
on the frequency.
Frequency
(c) The stopping potentials
are different for Na and Al for the same change in
frequency
(d) Al is a better photosensitive material than Na.
Stopping potential
11
1298The element with electronic
configuration 2,8,6 is
A. metallic
B. non-metallic
c. metalloid
D. None of these
11
1299One molecule of a substance absorbs
one quantum of energy. The energy involved when 1.5 moles of the
substance absorb red light of frequency
( 7.5 times 10^{14} s e c^{-1} ) will be?
A ( cdot 4.49 times 10^{5} J )
B . ( 2.24 times 10^{5} J )
c. ( 9.23 times 10^{7} J )
D. ( 2.24 times 10^{7} J )
11
1300A radioactive atom ‘ ( X^{prime} ) emits a ( beta- )
particle to produce an atom ‘ ( Y ) ‘ which
then emits an ( alpha ) -particle to given an
( operatorname{atom}^{prime} Z^{prime}: )
(1) The atomic number of ‘ ( X^{prime} ) is less
than that of ( ^{prime} Z^{prime} )
(2) The atomic number of ‘ ( Y ) ‘ is less
than that of ( ^{prime} Z^{prime} )
(3) The mass number of ‘ ( X^{prime} ) is same as
that of ‘ ( Y )
A. 1,2 and 3 are correct
B. 1 and 2 are correct
c. 2 and 3 are correct
D. 3 is correct
11
1301The lightest radioactive isotope in periodic table is:
A. tritium
B. deuterium
c. protium
D. none of these
11
13022.18 Out of the following pairs of electrons, identify the pairs of electro
present in degenerate orbitals.
(a) (i) n = 3, 1=2 , m = -2 ,m, =-= (ii) n = 3,1=2 m = -1, m,
(b) (i)n=3,1=1, m, =1, m = + (ii) n = 3, 1=2, m, =1, m, = +
II
+
(c) (i)n=4,1 =1, m, =1, m, = +
(ii) n=3,1=2, m, =1, m= +
+
(d) (i) n=3,1=2, m, = +2,m=-
(ii) n=3, 1=2,m, = +2,m,
+
11
1303The number of nodal planes in a ( boldsymbol{P}_{boldsymbol{x}} ) orbital is:
A. one
B. Two
c. Three
D. zero
11
1304Calculate the frequency of the radiation emitted when an electronjumps from ( n=3 ) to ( n=2 ) in a hydrogen atom is:
A ( cdot 4.57 times 10^{14} s^{-1} )
В. ( 4.57 times 10^{16} s^{-1} )
( c cdot 5.01 times 10^{14} s^{-1} )
-1
D. ( 5.01 times 10^{16} s^{-1} )
11
1305Electrons with a kinetic energy of
( 6.023 times 10^{4} J / ) mol are evolved from the
surface of a metal when it is exposed to
radiation of a wavelength of 600 nm. The minimum amount of energy
required to remove an electron from the metal atom is:
A ( .2 .3125 times 10^{-19} mathrm{J} )
B . ( 3 times 10^{-19} J )
( c cdot 6.02 times 10^{-19} J )
( J )
D. ( 6.62 times 10^{-34} J )
11
1306The number of electrons in a neutral
atom is equal to its:
A. atomic mass number
B. neutron
c. valency
D. proton
11
1307The ion that has different number of
electrons in the ultimate and
penultimate shells is :
A . ( N a^{text {t }} )
в. ( K^{+} )
c. ( C l^{-} )
D. ( C a^{2} )
11
1308Calculate the ratio of radii of first,
second and third orbits of a hydrogen
atom
11
1309A gas absorbs a photon of ( 355 n m ) and
emits two wavelengths. If one of the emission is at ( 680 n m ), the other is at:
( mathbf{A} .518 n m )
в. ( 1035 n m )
c. ( 325 n m )
D. ( 743 n m )
11
1310The energy change in an electron jump is given by:
A. ( Delta E=h c / lambda )
B. ( Delta E=h lambda / c )
c. change in kinetic energy
D. azimuthal quantum number
11
In Rutherford’s model of atom:
This question has multiple correct options
A. atom is a planetary model
B. electrons never loose nor gain energy
C. electron revolve around nucleus with high velocities to counter balance the forces of electrostatic forces of
attraction between protons and electrons
D. electrons do not move at all
11
1312The wavelength of radiation emitted, when in ( H e^{+} ) electron falls from infinity
to ground state would be:
( left(R=1.097 times 10^{7} m^{-1}right) )
A ( .2 .2 times 10^{-8} m )
th
B. 2.2 ( times 10^{-9} mathrm{m} )
c. ( 120 m )
D. ( 22 times 10^{7} mathrm{m} )
11
1313Calculate the wave number of the fourth
line of Balmer series.
11
1314Electronic configuration of chlorine is :
A ( cdot 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{1} 3 p^{6} )
B . ( 1 s^{2} 2 s^{2} 2 p^{5} 3 s^{2} 3 p^{6} )
c. ( 1 s^{2} 2 s^{2} 2 p^{6} 4 s^{2} 4 p^{5} )
D. ( 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{5} )
11
1315The number of unpaired electrons in chromium atom are:
A .2
B. 3
( c cdot 4 )
( D )
11
1316The wave number of the radiation whose
quantum 1 erg is:
A. ( 5 times 10^{15} mathrm{cm}^{-1} )
B. ( 15 times 10^{5} mathrm{cm}^{-1} )
c. ( 1.5 times 10^{15} mathrm{cm}^{-1} )
D. ( 5 times 10^{5} mathrm{cm}^{-1} )
11
1317In hydrogen spectrum, the spectral line of Balmer series having lowest wavelength is:
A. ( H_{alpha}- ) line
B. ( H_{beta}- )line
( mathbf{c} cdot H_{gamma}-operatorname{line} )
D. ( H_{delta}- ) line
11
1318Which of the following statements is
correct?
A. The maximum number of unpaired electrons in a subshell is equal to ( 2 l+1 )
B. The maximum value of magnetic moment for an atom with ( l=2 ) subshell is 3.9
C. The total spin of ( 3 d^{6} ) configuration is 3.
D. Both A and B
11
1319What will be the number of waves
formed by a Bohr electron in one complete revolution in its second orbit?
A. Three
B. Two
c. one
D. zero
11
1320The angular part of the wave function
depends on the quantum numbers are:
This question has multiple correct options
( A cdot n )
B. ( l )
( c . m )
D.
11
1321The commonly used pain reliever, aspirin, has the molecular formula
( C_{9} H_{8} O_{4} . ) If a sample of aspirin contains
( 0.968 g ) of carbon, what is the mass of hydrogen in the sample?
A ( .0 .717 g )
в. ( 0.0717 g )
c. ( 8.000 g )
D. ( 0.645 g )
11
1322A hydrogen atom initially in the ground level absorbs a photon, which excites it
to the ( n=4 t h ) level. Determine the
wavelength and frequency of photon.
11
1323Q42. An element with mass number 81 contains 31.7% more neutrons as compared to protons.
Assign the symbol to the element.
11
1324is defined as the number of protons present in the nucleus of an atom.
A. Atomic number
B. Mass number
c. Both a and
D. None of these
11
1325For an atom of a given element, the number of electrons is given by
A. the number of protons ( + ) number of neutrons
B. the atomic number of the element
c. the number of proton – number of neutrons
D. the mass number of the element
11
1326State True or False:
The electron density in ( x y ) -plane of
( 3 d_{x^{2}-y^{2}} ) orbital is zero.
A. True
B. False
11
1327Assertion
All the isotopes of a given element show same chemical behaviour.
Reason
Isotopes have different number of
neutrons present in the nucleus.
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
11
1328Bohr’s theory is not applicable for:
A . ( H )
B . ( L i^{2} )
( mathrm{c} cdot H^{+} )
D. ( B e^{3} )
11
1329For the Paschen series the value of ( n_{1} )
and ( n_{2} ) in the expression ( Delta E=R_{H} times ) ( cleft[frac{1}{n_{1}^{2}}-frac{1}{n_{2}^{2}}right] ) is:
A ( cdot n_{1}=1, n_{2}=2,3,4 )
в. ( n_{1}=2, n_{2}=3,4,5 dots )
c. ( n_{1}=3, n_{2}=4,5,6 )
D. ( n_{1}=4, n_{2}=5,6,7 )
11
1330Which of the following would not be attracted or deflected while traveling through an electric field?
I. Gamma ray
II. Beta particle
III. neutron.
A . i only
B. ii only
c. i and ii only
D. i and iii only
11
1331The excited state(n) of the atom is :11
1332The de-Broglie wavelength of a ( H e- )
atom in a container at ( 300 K ) is:
( left(operatorname{luse} v_{a v g}right) )
( mathbf{A} cdot 0.79 stackrel{circ}{A} )
B ( cdot 0.45 stackrel{circ}{h} )
( c cdot 0.68 stackrel{circ}{8 A} )
D. ( 0.89 stackrel{circ}{A} )
11
1333Which shape is associated with the orbital designated by ( n=2, l=1 ? )
A. Spherical
B. Tetrahedral
c. Dumb-bell
D. Pyramidal
11
1334The electronic configuration of an element is ( 1 s^{2}, 2 s^{2} 2 p^{6}, 3 s^{2} 3 p^{6} 3 d^{5}, 4 s^{1} )
This represents its:
A. excited state
B. ground state
c. cationic form
D. anionic form
11
1335Matter has both
A. mass, volume
B. mass, weight
C. life, particle
D. None of the above
11
1336In the hydrogen atom, the kinetic energy
of the electron is ( 3.4 e V . ) The distance of
that electron from the nucleus:
A . ( 2.116 AA )
в. ( 0.529 AA )
c. ( 1.587 hat{h} )
D. ( 21.16 AA )
11
1337Give the name and symbol for each of the atoms which have the ground state electronic configuration in their outer shells:
( (a) 2 s^{2}(b) 3 s^{2} 3 p^{5}(c) 3 s^{2} 3 p^{6} 4 s^{2}(d) 3 s^{2} 3 p^{6} )
11
1338Q11. What is common between d and d 2,2 orbitals?
XY
11
1339For which of the following orbital wave function does not change its sign at any distance from the nucleus?
A. 3d
B. 2p
( c cdot 2 s )
( D cdot 1 ) s
11
1340How does the Bohr theory of the
hydrogen atom differ from that of Schrodinger?
11
1341The change in orbital angular
momentum corresponding to an electron transition inside a hydrogen
atom can be:
A ( frac{h}{4 pi} )
в. ( frac{h}{p i} )
( c cdot frac{h}{2 pi} )
D. ( frac{h}{8 pi} )
11
1342Why can no two elements have a same
atomic number?
11
1343If series limit (in ( n m ) ) of a series of
hydrogen spectrum which contains a photon of wavelength 1278.35 nm is expressed as ( frac{1240}{x}, ) then ( x ) is:
(Given ( : h c=1240 mathrm{eV}-mathrm{nm}) )
A . ( 1.51 e V )
в. ( 2 e V )
c. ( 3.4 e V )
D. ( 0.66 e V )
11
1344Write down the four quantum number
for ( 8 t h ) electron of oxygen atom?
A ( cdot n=2, l=1, m=+2 ) or ( -2, s=+frac{1}{2} ) or ( -frac{1}{2} )
B. ( n=2, l=1, m=+1 ) or ( -1, s=+frac{1}{2} ) or ( -frac{1}{2} )
c. ( n=2, l=1, m=0, s=+frac{1}{2} ) or ( -frac{1}{2} )
D. ( n=2, l=0, m=0, s=+frac{1}{2} ) or ( -frac{1}{2} )
11
1345Which of the following orbitals are in the increasing order of energy.
( mathbf{A} cdot 1 s, 2 s, 2 p, 3 s )
В. ( 4 s, 3 s, 3 p, 4 d )
c. ( 5 p, 4 d, 5 d, 4 f, 6 s )
D. ( 4 p, 2 s, 3 s, 2 p )
11
1346If the following matter waves travel with equal velocity, the longest wavelength is that of a/an:
A . electron
B. proton
c. neutron
D. particle
11
1347Which of the following choices shows the ground state electron configuration of an ion of a halogen?
( mathbf{A} cdot 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{5} )
B . ( 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} )
C ( cdot 1 s^{2} 2 s^{2} 2 p^{6} 2 d^{10} 3 s^{2} 3 p^{5} )
D. ( 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 3 d^{1} )
11
1348Assertion
Number of waves in an orbit of atom is
equal to number of that orbit,
Reason
Number of waves in an orbit is derived by ( frac{2 pi r_{n}}{lambda} )
Read the above assertion and reason
and choose the correct option regarding
¡t
A. Statement is correct but Explanation is wrong.
B. Statement is wrong but Explanation is correct.
c. Both Statement and Explanation are correct and Explanation is the correct explanation for Statement
D. Both Statement and Explanation are correct but Explanation is not the correct explanation for Statement
11
1349Which is the correct graph?
( A )
B.
( c )
( D )
11
1350Which of the following contains up to 10
electrons.
A . ( 1 s )
B . ( 2 s )
( c cdot 3 s )
D. ( 3 p )
E . ( 3 d )
11
1351Thomson”s atomic model concluded
that is the constituent particle of all kinds of atom.
A . electron
B. protron
c. neutron
D. None of these
11
1352The kinetic energy of an electron accelerated from rest through a potential difference of 5V will be:
A . ( 5 ~ J )
B. 5 erg
( c .5 e V )
D. ( 8 times 10^{-10} ) eV
11
1353What is the lowest value of ( n ) that allows
g orbitals to exist?
11
1354What is the shape of f-orbital?
A. spherical
B. dumb bell
c. double dumb bell
D. no definite shape
11
1355An odd electron molecule among the following is :
A. ( C O )
в. ( S O_{2} )
( c cdot C O_{2} )
D. ( N O )
E. ( O F_{2} )
11
1356State True or False.
Electron was discovered by Goldstein.
A. True
B. False
11
1357Matter is composed of:
A. atoms
B. molecules
C . tiny particles
D. all of the above
11
1358The velocities of two particles ( A ) and ( B ) are 0.05 and ( 0.02 m s^{-1} ) respectively.
The mass of ( B ) is five times the mass of
A. The ratio of their de-Broglie’s wavelength is :
A .2: 1
B. 1: 4
( c cdot 1: 1 )
D. 4: 1
11
1359From the ( alpha ) -particle scattering
experiment, Rutherford concluded that:
This question has multiple correct options
A. ( alpha ) -particles can approach within a distance of the order of ( 10^{-14} mathrm{m} ) of the nucleus
B. the radius of the nucleus is less than ( 10^{-14} m )
C . scattering follows Coulomb’s law
D. the positively charged parts of the atom move with extremely high velocities
11
1360According to JJ Thomson’s atomic model, negative charges are embedded
in:
A. a lump of positive charge
B. a lump of neutral particles
c. alump of small atoms
D. the nucleus
11
1361The highest energy in Balmer series, in the emission spectra of hydrogen is represented by:
( left(R_{H}=109737 mathrm{cm}^{-1}right) )
( mathbf{A} cdot 4389.48 mathrm{cm}^{-1} )
в. ( 2194.74 mathrm{cm}^{-1} )
c. ( 5486.85 mathrm{cm}^{-1} )
D. 27434.25cm”
11
1362The energy of an electron in H atom is
( -3.4 e V . ) If the angular momentum of
the electron is ( x times 10^{-34} J sec ^{-1}, ) then ( x )
is:
A . 2.3
B. 2.1
c. 3.
D. 3.3
11
1363What the movement of solid particles caused by collisions with the constantly moving molecules of a gas is called?11
136472. When photons of wavelength 2, are incident on an
isolated sphere suspended by an insulated thread, the
corresponding stopping potential is found to be V. When
photons of wavelength are used, the corresponding
stopping potential was thrice the above value. If light of
wavelength is is used, calculate the stopping potential for
this case.
11
1365The energy of an electron in the first Bohr orbit of H atom is -13.6e ( V ). The
possible energy value(s) of the excited
state for electrons in Bohr orbits of ( L i^{2+} )
is:
A. ( -61.2 e V )
B. ( -13.6 e V )
c. ( -122.4 e V )
D. ( +6.8 e V )
11
1366What do you think would be the observation if the ( alpha ) -particle
scattering experiment is carried out
using a foil of a metal other than gold?
A. ( alpha ) particles would deflect by the foil by large angles
B. Most of the fast moving ( alpha ) particles would not pass straight through the metal foil
c. There would be no change in the observation
D. All particles would appear rebound
11
1367Which have the same number of ( s ) –
electrons as the ( d ) -electrons in ( F e^{2+} ? )
( mathbf{A} cdot L i )
в. ( N a )
( c cdot N )
D. ( P )
11
1368Which orbital has two angular nodal
planes ?
( A cdot s )
B. ( p )
( c cdot d )
D. ( f )
11
1369A sample of H-atoms containing all the
atoms in some excited state is
irradiated with light of wavelength ( lambda ) and the atoms get re-excited to further
higher orbit. On removing the light source, atoms de-excite to ground state
emission spectrum thus obtained
consists of ten spectral lines corresponding to ten different wavelengths. Out of the ten spectral lines, seven lines have the wavelength
smaller than the incident llambda,
while only two of them have
wavelengths longer than the incident wavelength. The orbit number in which electrons were present initially is:
A. 3
B. 4
( c cdot 5 )
( D .6 )
11
1370There is a stream of neutrons with a
kinetic energy of ( 0.0327 mathrm{eV} ). If the half-
life of neutrons is 700 second, the
percentage fraction of neutron will
decay before they travel a distance of 10 ( mathrm{km} ) is (multiply answer by 20). (mass of neutron ( =1.675 times )
( left.10^{-27} k gright) )
11
1371The number of lobes in most of the ( d )
orbits are:
A. 6
B. 10
( c cdot 8 )
D. 4
11
1372The triad of nuclei that is isotonic is:
( mathbf{A} cdot_{6}^{14} C, frac{15}{7} N,_{9}^{17} F )
В . ( _{6}^{12} C, frac{14}{7} N, ) ‘ ( _{19}^{9} F )
( mathbf{C} cdot_{6}^{14} C, frac{14}{7} N,_{9}^{17} F )
( mathbf{D} cdot_{6}^{14} C, frac{14}{7} N, frac{19}{9} F )
11
1373Which of the following ions has the maximum magnetic moment?
( mathbf{A} cdot M n^{+2} )
B. ( F e^{+2} )
( c cdot T i^{+2} )
D. ( C r^{+2} )
11
1374The particles present in the nucleus of an atom are :
A. the proton and the electron
B. the electron and the neutron
c. the proton and the neutron
D. none of these
11
1375Calculate
(a) frequency and (b) wave-
wavelength ( 5800 A )
11
1376The difference between the mass
number and the atomic number gives
the
A. number of neutrons
B. number of electrons
c. charge of an element
D. number of protons
11
1377Scientist previously thought an atom looked like plum pudding. In this model, it was assumed that protons and electrons were distributed throughout the atom almost randomly. Which of the following contributions DISPROVED the Plum Pudding model?
A. Rutherford’s Gold Foil Experiment.
B. J.J. Thomson’s Cathode Ray Experiment.
c. Millikan’s Oil Drop Experiment
D. Bohr’s Model of the Atom.
11
1378What element has a H-like spectrum, whose lines have wavelengths four times shorter than those of atomic
hydrogen?
A . не
B . ( mathrm{He}^{+} )
( c cdot H )
( D cdot L i^{2} )
11
1379Name the group of lines in the visible region of the hydrogen spectrum.11
1380The energy released during the transition of ( 3^{r d} ) orbit to ( 2^{n d} ) orbit is
equal to the difference of energy of the two levels.
A. True
B. False
11
1381A) Rutherford’s alpha parcticle scattering experiment led to the discovery of the
B) Isotopes have same but
different
C) Neon and chlorine have atomic numbers 10 and 17
respectively. Their valencies will be and
D) An atom with 3
protons and 4 neutrons will have a
valency of
11
1382The number of lobes in most of the d-
orbitals are:
A. 6
B. 8
c. 10
( D )
11
1383The number of quantum numbers required for the designation of an orbital in an atom is:
( A )
B. 2
( c cdot 3 )
D. 4
11
1384Alveoli ane the tiny sacks of air in lungs
whose average diameter is ( 5 times 10^{-5} mathrm{m} )
Consider a oxygen molecule ( (5.3 times )
( mathbf{1 0}^{-mathbf{2 6}} mathbf{k g} ) ) trapped within a sec
Calculate uncertainty in velocity of oxygen molecule.
A ( cdot 1.98 times 10^{-5} m s^{-1} )
В . ( 2 times 10^{-8} mathrm{ms}^{-1} )
( mathbf{c} cdot 5 times 10^{-5} m s^{-} )
D. ( 3 times 10^{-8} mathrm{ms}^{-1} )
11
1385Which of the following pairs constitute isotones?
A ( cdot frac{i 3}{6} mathrm{C} ) and ( frac{14}{6} mathrm{C} )
B . ( _{6}^{13} C ) and ( frac{14}{7} N )
C ( cdot frac{44}{7} N ) and ( _{9}^{19} F )
D. ( frac{14}{7} N ) and ( frac{15}{7} N )
11
1386(a) PE decreases, TE decreases
10. If the electron in an hydrogen atom jumps from an orbit
with level ny = 3 to an orbit with level n = 2, the emitted
radiation has a wavelength given by
. 36
(a) 1 =
(b) 2 = 5R
(c) 2 =
(d) a=
11
1387After ( n p ) -orbitals are filled, the next orbital filled will be:
A ( cdot(n+1) s )
B ( cdot(n+2) p )
( mathbf{c} cdot(n+1) d )
D. ( (n+2) s )
11
1388Assertion
According to de Broglie, the wavelengths associtated with electrons and other subatomic particles can be
detected experimentally.
Reason
The wavelength associated with any material particle is directly proportional
to its mass.
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
11
1389In 1911 came to the
conclusion that the atom had a dense
nucleus because most of the particles shot straight through, but some of the particles were deflected due to the dense nucleus of the gold atoms.
A. Thompson
c. Rutherford
D. none of the above
11
1390In a photoemissive cell with executing wavelength ( lambda ), the fastest electron has to speed v. If the exciting wavelength is changed to ( frac{3 lambda}{4}, ) the speed of the fastest emitted electron will be:
( ^{mathrm{A}} vleft(frac{3}{4}right)^{1 / 2} )
в. ( _{v}left(frac{4}{3}right)^{1 / 2} )
( ^{mathrm{c}} cdot operatorname{lessthan} vleft(frac{4}{3}right)^{1 / 2} )
D. greater than ( vleft(frac{4}{3}right)^{1 / 2} )
11
1391The wavelength of light is 8000 A. The no. of photon required to provide 20 J of energy is approximately:
A ( cdot 4.56 times 10^{18} )
B . ( 8 times 10^{19} )
c. ( 7 times 10^{19} )
D. ( 4 times 10^{7} )
11
1392The atomic weight of Ne is 20.2. Ne is mixture of ( N e^{20} ) and ( N e^{22} . ) The relative
abundance of the heavier isotope is:
A . ( 90 % )
B. 20%
c. ( 40 % )
D. ( 10 % )
11
1393Which of the following conclusions
cannot be drawn on Rutherford’s atomic
model?
A. The total mass of an atom is concentrated at the
centre of the atom
B. Nucleus is located inside the atom containing positively charged particles
C. Most of the atom is empty in space
D. Electrons revolve around the nucleus in stationary, circular orbits
11
1394Which one has the electronic
configuration given below? ( 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{1} )
A . ( N a^{+} )
в. ( A l )
( c . F )
D. ( T i )
E . ( B r )
11
1395Emission transitions in the Paschen
series end at orbit ( n=3 ) and start from
orbit ( n ) and can be represented as ( v= )
( mathbf{3} . mathbf{2 9} times mathbf{1 0}^{mathbf{1 5}}(mathbf{H z})left[mathbf{1} / mathbf{3}^{mathbf{2}}-mathbf{1} / mathbf{n}^{mathbf{2}}right] )
Calculate the value of ( n ) if the transition
is observed at 1.285 nm. Find the region
of the spectrum.
11
1396Find the number of photons of radiation of frequency ( 5 times 10^{13} s^{-1} ) that must be
absorbed in order to melt one gm ice when the latent heat of fusion of ice is
( mathbf{3 3 0} mathbf{J} cdotleft(mathbf{h}=mathbf{6 . 6} times mathbf{1 0}^{-mathbf{3 4}} mathbf{J} times mathbf{s e c} .right) )
11
1397Uncertainity in position of a particle of ( 25 mathrm{g} ) in space is ( 10^{-15} mathrm{m} . ) Determine
uncertainity in velocity ( left(mathrm{m} mathrm{sec}^{-1}right) ) in it. (plank’s constant, ( boldsymbol{h}=mathbf{6 . 6} times mathbf{1 0}^{-mathbf{3 4}} mathbf{J s} ) )
A . ( 2.1 times 10^{-18} )
В. ( 1.2 times 10^{-18} )
c. ( 1.8 times 10^{-18} )
D. ( 2.5 times 10^{-18} )
11
1398An atom of an element contains 29
electrons and 35 neutrons.
Deduce
(i) the number of protons and
(ii) the electronic configuration of the element.
11
1399State True or False.
Hydrogen atom can produce single spectral line due to a presence of one
electron.
A. True
B. False
11
1400The configuration ( 1 s^{2} 2 s^{2} 2 p^{5} 3 s^{1} ) shows:
A. excited state of ( O_{2}^{-} )
B. excited state of neon atom
c. excited state of fluorine atom
D. ground state of fluorine atom
11
1401The electron present in the 5th orbit in an excited hydrogen atom returns back to the ground state. The number of lines
which appear in Lyman series of hydrogen spectrum is:
A . 5
B. 10
( c cdot 4 )
D. 6
11
1402The maximum probability of finding
electron in the ( d_{x y} ) orbital is
A. Along with ( x ) – axis
B. Along the ( y ) – axis
C. At an angle of ( 45^{0} ) from the ( X ) and Y axis
D. At an angle of ( 90^{0} ) from the ( x ) and ( y ) axis
11
1403How much energy is required to ionise ( mathrm{H} ) atom if the electron occupies ( n=5 ) orbits? Compare your answer with the ionization enthalpy of H atom [ energy required to remove the electron from ( n=1 text { orbit }] )11
1404Which statement about a ( 3 p ) orbital is
correct?
A. It can hold a maximum of 6 electrons
B. It has the highest energy of the orbitals with principal quantum number 3
C. It is at a higher energy level than a 3 s orbital but has the same shape
D. It is occupied by one electron in an isolated phosphorous atom
11
1405Assertion
An element (X) with an atomic number
of 16 has 14 electrons in ( X^{2-} )
Reason
Two protons bind the two outermost electrons
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
11
1406Containers ( X, Y ) and ( Z ) of the equal
volume contain oxygen, neon and methane respectively at the same temperature and pressure. The correct increasing order of their masses is:
A. ( X<Y<Z )
в. ( Y<Z<X )
c. ( Z<X<Y )
D. ( Z<Y<X )
11
1407Match the pairs.11
1408Which of the following transition in
( H e^{+} ) ion emits light of wavelength
equal to the longest wavelength emitted in the Paschen series H-atom?
( mathbf{A} cdot 9 rightarrow 6 )
B . ( 8 rightarrow 6 )
c. ( 8 rightarrow 4 )
D. none of these
11
1409If spin quantum number are ( -frac{1}{2}, 0,+frac{1}{2} ) based on the above assumption electronic configuration of the elements with atomic number 30 is:
B . ( 1 s^{3} 1 p^{15} 2 s^{3} 1 d^{9} )
C ( cdot 1 s^{9} 1 p^{15} 2 s^{6} )
D cdot ( 1 s^{3} 19^{p} 2 s^{3} 2 p^{9} 1 d^{6} )
11
1410Charge on electron of mass ( 9.109 times )
( 10^{-31} mathrm{Kg} ) is:
A ( cdot 1.603 times 10^{-19} mathrm{C} )
В. ( -1.603 times 10^{-19} mathrm{C} )
c. ( 9.109 times 10^{-31} mathrm{C} )
D. ( -9.109 times 10^{-31} mathrm{C} )
11
1411Isotopes of cobalt ( ldots ) used in the
treatment of cancer
A. ( C o-59 )
в. ( C o-60 )
c. ( C o-61 )
D. ( C o-62 )
11
1412The de-brogile wavelength of an electron in the ground state of hydrogen atom is:
( [boldsymbol{K} . boldsymbol{E} .=mathbf{1 3 . 6} e boldsymbol{V} ; mathbf{1} e boldsymbol{V}=mathbf{1 . 6 0 2} times )
( mathbf{1 0}^{-mathbf{1 9}} boldsymbol{J} )
A. ( 33.28 n m )
B. ( 3.328 n m )
( mathbf{c} .0 .3328 n m )
D. ( 0.0332 n m )
11
14138. Consider a hydrogen like atom whose energy in n’hexicited
13.622
state is given by En=–
when this excited atom
makes a transition from excited state to ground state, most
energetic photons have energy Emax = 52.224 eV and least
energetic photons have energy Emin= 1.224 eV. The atomic
number of atom is
(a) 2
(b) 5
(c) 4
(d) None of these
11
1414Which one of the following corresponds to a photon of highest energy?
A ( . lambda=300 n m )
В . ( v=3 times 10^{8} s^{-1} )
c. ( v=30 c m^{-1} )
D . ( varepsilon=6.626 times 10^{-27} J )
11
1415How to find atomic mass of any
element, explain.
11
1416An electron in ( 2^{n d} ) orbit gains energy
and goes to ( 4^{t h} ) orbit. What are the
difference in angular momentums experienced by the electron due to the transition?
11
1417The cathode ray experiment is conducted in a discharge tube containing four different gases ( A, B, C ) and ( D, ) the molecular weight of ( A=B>D ) ( >mathrm{C}, ) then ( mathrm{e} / mathrm{m} ) as observed will be:
( A cdot A>B>D>C )
B. ( A<D<Bmathrm{D}>mathrm{C} )
D. ( A=B=C=D )
11
1418Cathode rays travel in
A. waves
B. packets
c. straight lines
D. alternative waves
11
1419USIC
UL SCICU
U
N
CICLE IL 10 TELLICOLTTUU UC UCICUS.
Q64. Among the following pairs of orbitals, which orbital will experience more effective nuclear
charge? (0) 2s and 3s (ii) 4d and 4f (iii) 3d and 3p?
Caltabil
11
1420Q1. Give the relation between welength and momentum of moving microscopic particle. What is
the relation known as?
11
1421An experiment requires minimum ( beta )
activity produced at the rate of ( 346 beta )
particles per minute. The half-life period of ( _{42}^{99} ) Mo which is a ( beta ) -emitter is 66.6 hr. The minimum amount of ( _{42}^{99} ) Mo required to carry out the experiment in 6.909 hour is :
A ( cdot 6.78 times 10^{-16} g )
В. ( 3.52 times 10^{-16} g )
c. ( 5.21 times 10^{-16} g )
D. none of these
11
1422Which of the following is true regarding an Ne atom with a mass number of 20
and an ( O^{2-} ) ion with a mass number of
( 16 ? )
A. The contain the same number of protons
B. The contain the same number of neutrons
C. The contain the same number of protons plus neutrons
D. They are isoelectronic.
E. They are isomers
11
1423Write electronic configurations of the elements with atomic number 17.11
1424Boron can not form more than 4 bonds
because:
This question has multiple correct options
A. of unavailability of d-orbitals
B. of unavailabilty of empty p-orbitals
C. Boron is so smaller
D. it does not have more valence electrons
11
1425The ions ( N^{3-}, O^{2-}, F^{-}, N a^{+}, M g^{2+} ) are isoelectronic. Their ionic radii shows:
A. an increase from ( N^{3-} ) to ( F^{-} ) and then decrease from ( N a^{+} ) to ( M g^{2+} )
B. a decrease from ( N^{3-} ) to ( F^{-} ) and then increase from ( N a^{+} ) to ( M g^{2+} )
C . a significant increase from ( N^{3-} ) to ( M g^{2+} )
D. a significant decrease from ( N^{3-} ) to ( M g^{2+} )
11
1426The orbital angular momentum of an
electron in 2 s orbitals is:
A ( cdot+frac{1}{2} frac{h}{2 pi} )
B. zero
( c cdot frac{h}{2 pi} )
D. ( sqrt{2} frac{h}{2 pi} )
11
1427If the radius of first Bohr orbit is ( x p m )
then the radius of the third orbit would
be:
в. ( (6 times x) ) рт
C ( cdotleft(frac{1}{2} times xright) p m )
D. ( (9 times x) p m )
11
1428Which of the following nuclei is unstable?
( mathbf{A} cdot_{5} B^{10} )
B. ( _{4} B e^{10} )
( mathrm{c} cdot_{7} N^{14} )
( mathrm{D} cdot_{8} mathrm{O}^{1} )
11
142945. In hydrogen and hydrogen-like atoms, the ratio of
E4n – E2n and E2n – En varies with atomic number z and
principal quantum number n as
(b)
?
(d) none of these
11
1430Which of the following statements given below is incorrect?
A. ( O N F ) is isoelectronic with ( O_{2} N^{-} )
B. ( O F_{2} ) is an oxide of fluorine
c. ( C l_{2} O_{7} ) is an anhhydride of perchloric acid
D. ( O_{3} ) molecule is bent.
11
1431An electron in the hydrogen atom is excited from ( 1^{s t} ) orbit to ( 5^{t h} ) orbit. The
A ( cdot 0.44 times 10^{-9} mathrm{Hz} )
В. ( 3.15 times 10^{15} mathrm{Hz} )
c. ( 6.2 times 10^{8} mathrm{Hz} )
D. ( 1.13 times 10^{-12} mathrm{Hz} )
11
1432Elements ( A, B, C, O ) and ( E ) having the following electronic configuration
(i) ( 1 s^{2}, 2 s^{2}, 2 p^{1} )
(ii) ( 1 s^{2}, 2 s^{2}, 2 p^{6}, 3 s^{2}, 3 p^{1} )
(iii) ( 1 s^{2}, 2 s^{2}, 2 p^{6}, 3 s^{2}, 3 p^{3} )
(iv) ( 1 s^{2}, 2 s^{2}, 2 p^{6}, 3 s^{2}, 3 p^{5} )
( (v) 1 s^{2}, 2 s^{2}, 2 p^{6}, 3 s^{2}, 3 p^{6} )
Electronic configurations belonging to
the same group are:
A. (i) and (iii)
B. (i) and (iv)
c. (i) and (ii)
D. (i) and (v)
11
1433Which of the following have highest
energy of electron?
( mathbf{A} cdot_{1} H^{1} )
В . ( _{1} H^{2} )
( mathbf{c} cdot_{1} H^{3} )
D. All have equal energy
11
1434The quantum yield for decompostion of ( H I ) is 0.2 In a experiment 0.01 moles of
( H I ) are decomposed. Find the number
of photons absorbed. ( left(N_{A}=6 times 10^{23}right) )
11
1435( frac{sqrt{6}}{frac{1}{4}} )11
1436Isotopes are atoms with the same number of protons, but differing numbers of neutrons. Isotopes are different forms of a single element.
A. True
B. False
11
1437In which element rule(c) (i) is followed?
A ( cdot 29^{c} )
B. 24 ( ^{c} )
( c cdot 26^{F e} )
D. ( 25^{M n} )
11
1438In the uranium radioactive series the
initial nucleus is ( _{92}^{238} mathrm{U} ) and the final nucleus is ( _{82}^{206} ) Pb. When the uranium nucleus decays to lead, number of ( alpha )
particles emitted is and the
number of ( beta ) -particles emitted is
11
1439Consider the hydrogen atom to be a
proton embedded in a cavity of radius
( a_{0} ) (Bohr’s radius), whose charge is
neutralized by the addition of an electron to the cavity in vacuum, infinitely slowly. Then the wavelength of the electron when it is at a distance of
( a_{0} ) from the proton will be
A ( cdot lambda=sqrt{frac{4 pi varepsilon_{0} a_{0}}{h^{2} e^{2} m}} )
B. ( lambda=sqrt{frac{4 pi varepsilon_{0} a_{0} h^{2}}{e m}} )
( ^{mathbf{c}} cdot_{lambda}=sqrt{frac{4 pi varepsilon_{0} a_{0} h^{2}}{e^{2} m}} )
D. ( lambda=sqrt{frac{4 pi varepsilon_{0} a_{0} h^{2}}{e^{5} m}} )
11
1440Bohr’s model could not explain the of multi electron
species.
A. spectra
B. nucleus
c. spin
D. orbital
11
1441If the energy difference between two electronic states is 46.12 kcal/mol;
What will be the frequency of light emitted when the electrons dropped from higher to lower states ( (N h= )
( 9.52 times 10^{-14} ) kcal sec mol ( ^{-1} ) ) where ( N )
11
1442Give the equation which explains the different series of lines in the atomic
spectrum of hydrogen. who is the equation named after? Explain the various terms involved.
11
1443Dual character of an electron was
explained by:
A. Bohr
B. Heisenberg
c. De Broglie
D. Pauli
11
144415. The first line in the Lyman series has wavelength 2. The
wavelength of the first line in Balmer series is
(b)2
11
1445Boron has two isotopes ( mathrm{B}-10 ) and ( mathrm{B}-11 . ) I the average atomic mass of boron is 10.80 u. What is the percentage of a heavier isotope?
A. 80
B. 20
( c . ) 30
D. 70
11
1446The disintegration energy ( Q ) for the change ( _{Z}^{A} mathbf{X} stackrel{-alpha}{longrightarrow} underset{Z-2}{A-4} mathbf{D}+Q ) is given by
( boldsymbol{Q}=left[boldsymbol{M}left(begin{array}{l}A mathbf{X} \ Zend{array}right)-boldsymbol{M}left(begin{array}{l}boldsymbol{A}-mathbf{4} \ boldsymbol{Z}-mathbf{2}end{array} mathbf{D}right)-right. )
( left.Mleft(_{2}^{4} mathbf{H e}right)right] C^{2}, ) where ( M ) represents the
mass of respective nuclei reported in
paranthesis and ( C ) is speed of light. For
( alpha ) -decay :
A. ( Q=+v e )
В. ( Q=-v e )
c. ( Q=0 )
D. not related with ( Q )
11
1447Which of the following is not the property of cathode rays: –
A. It produces heating effect
B. It does not deflect in electric field
D. It produces flurosence
11
1448What are the limitations of
J.J.Thomson’s model of the atom?
11
1449Select a lustrous material out of the
following substances.
Gold, Sand, Silver, Rubber
11
1450‘n spectrum corresponds to the
… This series lies in the visible
0.32 The Balmer series in the hydrogen spectrum
transition from n = 2 to n = 3, 4, ….. This senes
region. Calculate the wave number of line associated
in Balmer series when the electron moves to n = 4 orbit.
(Rx = 109677 cm-2)
11
1451If ( E_{1}, E_{2} ) and ( E_{3} ) represent respectively the kinetic energies of an electron, an alpha particle and a proton each having same de Broglie wavelength then:
A. ( E_{1}>E_{3}>E_{2} )
в. ( E_{2}>E_{3}>E_{1} )
c. ( E_{1}>E_{2}>E_{3} )
D. ( E_{1}=E_{2}=E_{3} )
11
1452Assertion
The ratio of radius of first orbit to
second orbit of hydrogen atom is 1: 4
Reason
Radius for each circular orbit ( = )
( mathbf{0 . 5 2 9} boldsymbol{n ^ { 2 }} boldsymbol{hat { A }} )
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
11
145360. If wavelength of photon emitted due to transition of an
electron from the third orbit to the first orbit in a hydrogen
atom is 2, then the wavelength of photon emitted due to
transition of electron from the fourth orbit to the second
orbit will be
11
11
1454Electrons are present in the nucleus of
an atom.
A . True
B. False
11
1455( alpha- ) particles can be detected using :
A. thin aluminium sheet
B. barium sulphate
c. zinc sulphide screen
D. gold foil
11
145634. The wavelength of the first line of Lyman series in
hydrogen atom is 1216. The wavelength of the first line
of Lyman series for 10 times ionized sodium atom will
(a) 0.1 Å
(b) 1000 Å
(c) 100 Å
(d) 10 Å
11
1457Which of the following is a state of
matter?
A. Quark-gluon plasma
B. Quantum spin liquid
c. superfluid
D. All of above
11
1458Uncertainly principle is valid for:
A. Proton
B. Methane
C. Both (proton) and (methane)
D. ( 1 mu m ) sized platinum particles
E . ( 1 mu m ) sized ( N a C l ) particles
11
1459( boldsymbol{H}_{alpha} ) line of Balmer series is ( mathbf{6 5 0 0} boldsymbol{A} ). The
wave length of ( boldsymbol{H} gamma ) is?
A. ( 4815 AA )
в. 4298 А
c. ( 7800 hat{h} )
D. 3800 月
11
1460The atomic weight of an atom is because of
A. electrons and protons
B. electrons and neutrons
c. neutrons and protons
D. electrons, neutrons and protons
11
1461Identify the error(s) in the orbital notation diagram for oxygen in the in
the image ( a )
a. ( prod_{1 mathrm{s}} frac{|uparrow downarrow|}{2 mathrm{s}} frac{|uparrow| downarrow|uparrow|}{2 mathrm{p}} )
( frac{sqrt{11}}{1 mathrm{s}} frac{sqrt{11}}{2 mathrm{s}} frac{sqrt{mathrm{t}} uparrow 1}{2 mathrm{p}} )
e. ( frac{sqrt{uparrow} mid}{1 s} )
[
frac{|uparrow| uparrow|uparrow|}{2 p}
]
This question has multiple correct options
A. The electrons are not drawn with the appropriate spins
B. This is not a picture of oxygen. It is nitrogen
c. The electrons are not filled out according to Aufbau’s’s Principle
D. The electrons are not filled out according to Hund’s Rule
11
1462Choose the correct statement among
the following.
This question has multiple correct options
( mathbf{B} cdotleft(Psi^{24 pi^{2}} d rright) )
C ( . Psi(r) Psi(theta) Psi(Phi))=Psi(x / y / z) ) is independent of ( theta ) and ( phi )
D. ‘2p’orbital with quantum numbers.n=2,|=1,m=0,also shows angular dependence
11
1463How long will it take a radiowave of
frequency ( 6 times 10^{3} s^{-1} ) to travel from one
place to other? The distance is ( 10^{14} k m )
11
1464Electrons are represented as:
( mathbf{A} cdot e )
B ( cdot e^{-} )
( mathbf{c} cdot e^{+} )
( mathrm{D} cdot e^{+} )
11
1465When an electron is transferred in
hydrogen atom from ( n=4 ) orbit to ( n=5 ) orbit to which spectral series does this belong?
11
1466In the emission line spectra of hydrogen atom, how many lines can be accounted for by all possible electron transitions
between five lowest energy levels within the atom?
( A cdot 4 )
B. 5
c. 10
D. 20
11
1467Which of the following is true for
Thomson’s model of the atom?
A. The radius of an electron can be calculated using Thomson’s model
B. In an undisturbed atom, the electrons will be at their
equilibrium positions, where the attraction between the cloud of positive charge and the electrons balances their mutual repulsion
C. When the electrons are disturbed by collision, they will vibrate around their equilibrium positions and emit electromagnetic radiation whose frequency is of the order of magnitude of the frequency of electromagnetic radiation of a vibrating electron
D. Both
(B) and (C)
11
1468A radioactive atom ( _{Y}^{X} M ) emits two ( alpha^{-} ) particles and one ( beta ) -particle
respectively. The number of neutrons in
the product nucleus will be :
( mathbf{A} cdot X-Y-4 )
B. ( X-5-Y )
c. ( X-3-Y )
D. ( X-Y-6 )
11
1469The highest value of ( e / m ) of anode rays has been observed when the discharge tube is filled with:
A. nitrogen
B. oxygen
c. hydrogen
D. helium
11
1470u
+
(0) 04
21. The orbital velocity of an electron in the ground sta
v. If the electron is excited to energy state -0.54 eV
orbital velocity will be
(a) v
11
1471The reaction;
( mathbf{9 2} boldsymbol{U}^{mathbf{2 3 8}}+mathbf{0} boldsymbol{n}^{mathbf{1}} rightarrow mathbf{9 2} boldsymbol{U}^{mathbf{2 3 9}} rightarrow mathbf{9 3} boldsymbol{N} boldsymbol{p}^{mathbf{2 3 9}}+ )
( -1 e^{0} )
is an example of:
A. ( alpha ) -emission
B. ( beta ) -emission
C ( . gamma ) -emission
D. none of these
11
1472The conclusion of Rutherford from his ( alpha )
-ray scattering experiment is:
A. many particles were deflected from their path, indicating that the positive charge of the atom occupies very small space.
B. many particles were deflected from their path, indicating that the positive charge of the atom occupies very large space.
C. most of the space inside the atom is empty because most of the ( alpha ) -particles passed through the gold foil without getting deflected.
D. a very large fraction of alpha-particles were deflected by ( 180^{circ} ), indicating that all the positive charges and mass of the gold atom were concentrated in a very small volume within the atom
11
1473At what velocity ratio ( frac{v_{e}}{v_{p}} ) are the wavelengths of an electron and a proton
equal?
( left(boldsymbol{m}_{e}=mathbf{9 . 1} times mathbf{1 0}^{-mathbf{2 8}} boldsymbol{g} quad boldsymbol{text {and}} quad boldsymbol{m}_{boldsymbol{p}}=mathbf{1 . 6 7}right. )
A. ( 1.2 times 10^{3} )
В. ( 1.8 times 10^{3} )
c. ( 2.4 times 10^{3} )
D. ( 1.6 times 10^{3} )
11
1474The number of lines of atomic hydrogen
spectrum fall within the wavelength
range from 94.5 to 130.0 nm is:
11
1475Neutron has a ( _{-1-} ) charge
A ( cdot ) tve
B. -ve
c. zero
D. None of these
11
1476Assertion
The radial probability distribution curves of ( 1 s, 2 p, 3 d- ) orbitals are identical in shape.
Reason
The number of nodal planes present in
these orbitals 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. Assertion is incorrect and Reason are correct
11
1477If the lowest energy X-rays have ( lambda= )
( 3.055 times 10^{-8} m, ) estimate the
minimum difference in energy between
two Bohr’s orbits such that an
electronic transition would correspond
to the emission of an X-ray. Assuming that the electrons in other shells exert
no influence, at what ( Z(text { minimum }) ) would a transition from a second energy
level to the first result in the emission
of an X-ray?
( mathbf{A} cdot mathbf{1} )
B. 2
( c cdot 3 )
D. 4
11
1478Find the frequency of light that
corresponds to photons of energy ( 5.0 times ) ( 10^{-5} ) erg.
( mathbf{A} cdot 7.5 times 10^{-21} sec ^{-1} )
В. ( 7.5 times 10^{-21} ) sec
c. ( 7.5 times 10^{21} ) sec ( ^{-1} )
D. ( 7.5 times 10^{2} ) sec
11
1479The isoelectronic set of ions is:
A ( cdot N^{3-}, L i^{+}, M g^{2+} ) and ( O^{2-} )
B. ( L i^{+}, N a^{+}, O^{2-} ) and ( F^{-} )
c. ( F^{-}, L i^{+}, N a^{+} ) and ( M g^{2} )
D. ( N^{3},, O^{2-}, F^{-} ) and ( N a^{+} )
11
1480Thomson’s model of atom is also known
as:
This question has multiple correct options
A. water-melon model
B. raisin pudding model
c. plum pudding model
D. Rutherford’s model
11
1481In hydrogen atomic spectrum, a series limit is found at ( 12186.3 mathrm{cm}^{-1} ). Then it
belongs to :
A. Lyman series
B. Balmer series
c. Paschen series
D. Brackett series
11
1482Identify the sets of electronic transitions associated with release of
energy and absorption of energy.
( A cdot n=4 ) to ( n=1 ; n=2 ) to ( n=1 )
B. ( n=4 ) to ( n=3 ; n=4 ) to ( n=2 )
( c cdot n=3 ) to ( n=5 ; n=2 ) to ( n=3 )
D. ( n=3 ) to ( n=2 ; n=1 ) to ( n=2 )
11
1483The number of nodal planes in each ( boldsymbol{p} )
orbital
( mathbf{A} cdot mathbf{0} )
B.
( c cdot 2 )
D. 3
11
1484If the energy difference between the
electronic states is ( 214.68 mathrm{kJ} mathrm{mol}^{-1} )
calculate the frequency of light emitted when an electron drops form the higher to the lower state Plank’s constant?
( h=39.79 times k J mathrm{mol}^{-1} )
A ( cdot 5.39 times 10^{14} ) cps
B. ( 5.99 times 10^{15} ) cps
C. ( 5.99 times 10^{14} ) cps
D. 5.39 ( times 10^{15} mathrm{cps} )
11
148574. Making use of the uncertainty principle, evaluate the minimum
permitted energy of an electron in a hydrogen atom and its
corresponding apparent distance from the nucleus.
11
1486How many of the following is the
matter?
Chair, Air, Heat, Smell, Sound, Almonds, Thought and Cold drink.
( A cdot 4 )
B. 5
( c cdot 6 )
D.
11
1487All the mass of the atom resides in the
A. nucleus
B. molecules
( c . ) ions
D. orbit
11
1488Which of the following is the most abundant isotope of chlorine?
A. Chlorine -35
B. Chlorine – 35.45
c. Chlorine-36
D. Chlorine -37
11
1489For ( n=5, ) the types of orbitals found in
shell is?
( A cdot s )
B. s, p
( c cdot s, p, d, f )
D. ( s, p, d, f, g )
11
1490The ratio of the radius of Bohr first orbit
for the electron orbiting the hydrogen nucleus to that of the electron orbiting the deuterium nucleus (mass nearly
twice that of nucleus) is approximately:
A . 1: 1
B. 1: 2
c. 2: 1
D. 1: 4
11
1491The unpaired electrons in ( A l ) and ( S i ) are present in ( 3 p- ) orbital. Which electron
will experience more effective nuclear
charge from the nucleus?
11
1492Which of the following series of transitions in the spectrum of hydrogen atom fall in visible region?
A. Lyman series
B. Balmer series
c. Paschen series
D. Brackett series.
11
1493Through what potential difference must an electron pass to have a wavelength of ( mathbf{5 0 0} boldsymbol{A} ? )
A ( cdot 6.03 times 10^{-3} ) ev
В. ( 3.01 times 10^{-4} mathrm{ev} )
( c cdot 6.03 times 10^{-5} mathrm{ev} )
( v )
D. ( 3.01 times 10^{-5} mathrm{ev} )
11
1494Magnesium hydroxide is the white milky substance in milk of magnesia.
What mass of ( M g(O H)_{2} ) is formed when ( 15 m l ) of ( 0.2 M-N a O H ) is
combined with ( 12 mathrm{ml} ) of ( 0.15 M- )
( M g C l_{2} ? )
A. ( 0.087 g )
в. ( 0.079 g )
c. ( 0.1044 g )
D. ( 0.522 g )
11
1495The energy of the electron in the second and third Bohr orbits of the hydrogen atom is ( -5.42 times 10^{-12} ) erg and ( -2.41 times 10 )
-12 erg, respectively. The wavelength of the emitted radiation when the electron
drops from third to second orbit is:
A ( .4 .6 times 10^{6} )
B . ( 6.6 times 10^{3} )
c. ( 0.66 times 10^{6} )
D. none of these
11
1496The value of Planck’s constant is
( 6.63 times 10^{34} mathrm{Js} . ) The speed of light is ( 3 times )
( 10^{17} mathrm{nm} s^{1} . ) Which value is closest to the
wavelength in nanometer of a quantum
of light with a frequency of ( 6 times 10^{15} s^{1} ? )
A . 10
B. 25
( c .50 )
D. 75
11
1497The difference in angular momentums associated with an electronic transition
in hydrogen atom is equal to ( 3 h / 2 pi . ) The atom contains only ( mathrm{K}, mathrm{L}, mathrm{M} ) and ( mathrm{N} ) shells. Calculate the energies and radii associated with the orbits.
A. -13.6 ev and 0.314 Angstrom, 0.08 eV and 8.48 Angstrom
B. -13.6 eV and 0.529 Angstrom, – 0.08 eV and 8.48 Angstrom
c. 13.6 ev and 0.529 Angstrom, 0.08 eV and 8.48 Angstromm
D. 27.2 eV and 0.529 Angstrom, 0.08 eV and 8.48 Angstrom
11
1498Calculate the number of electrons in
sulphur atom having ( boldsymbol{n}+boldsymbol{l}=mathbf{3} )
( A cdot 2 )
B. 4
( c .6 )
D.
11
1499Rutherford’s ( alpha ) -scattering experiment
led to the following conclusions:
A. atom has largely completely filled space
B. the centre of the atom has negatively charged nucleus
C. the size of the nucleus is very small as compared to the size of the atom
D. electrons revolve around the proton
11
1500Quantum numbers ( l=2 ) and ( m=0 )
represent which orbital?
A ( cdot d_{x y} )
B. ( d_{x^{2}-y^{2}} )
( c cdot d_{z} )
D. ( d_{x x} )
11
1501In a given electric field, ( beta- ) particles are
deflected more than ( alpha- ) particles, inspite of ( alpha- ) particles having larger charge.
A. True
B. False
11
1502Complete the following nuclear
equation:
( _{26}^{69} mathrm{Fe} rightarrow beta+_{-}- )
( mathbf{A} cdot_{25}^{58} mathrm{Mn} )
B . ( frac{58}{27} mathrm{Co} )
( mathbf{C} cdot_{25}^{59} mathrm{Mn} )
( D cdot frac{59}{27} mathrm{Co} )
E ( . begin{array}{c}60 mathrm{Mn} \ 25end{array} )
11
1503( B e^{2+} ) is isoelectronic with which of the
following ions?
A . ( H^{+} )
B . ( L i^{+} )
( c cdot N a^{+} )
D. ( M g^{2+} )
11
15044.16 ( g ) of ( B a C I_{2} ) contains ( 2.74 g ) of Ba.
The atomic weight of Ba is nearly:
A .137
B. 208
c. 67.3
D. 97.27
11
1505Which of the following is/are incorrect for Humphrey lines of hydrogen spectrum? This question has multiple correct options
A ( cdot n_{2}=7 rightarrow n_{1}=2 )
В ( cdot n_{2}=10 rightarrow n_{1}=6 )
c. ( n_{2}=5 rightarrow n_{1}=1 )
D ( cdot n_{2}=11 rightarrow n_{1}=3 )
11
1506A particle ( X ) deflects towards negative plate in the presence of electric field. Identify the particle ( X ? )
A. Neutron
B. Electron
c. ( X ) -ray
D. Proton
11
1507The doubly ionized lithium atom is
hydrogen-like with the atomic number ( z=3 . ) Find the wavelength of the
radiation required to excite the electron
in ( L i^{2+} ) from the first to the third Bohr
orbit is:
( left[text { Given: } frac{1}{boldsymbol{R}_{boldsymbol{H}}}=mathbf{9 1 2} boldsymbol{A}right] )
( mathbf{A} cdot 114 stackrel{circ}{A} )
B ( cdot 156^{circ} )
( mathbf{c} cdot_{180 stackrel{circ}}{mathbf{h}} )
D ( cdot 201 stackrel{circ}{A} )
11
1508The atomic number of magnesium is 12 The number of protons in the nucleus of magnesium atom is:
( A cdot 6 )
B. 10
c. 12
D. 24
11
1509There have been certain objectives
against food preservation by
This question has multiple correct options
B. irradiation can destroy the the nutrients such as vitamins and amino acids
C. ionising radiation produces reactive species such as the hydroxyl radical which then react with organic molecules to produce potentially harmful substances.
D. irradiated food may be much costlier
11
1510The number of unpaired electrons in ( M n^{4+}(z=25) ) is :
A. four
B. two
c. five
D. three
11
1511Define nucleus.11
1512Q. 7 Two atoms are said to be isobars if
(a) they have same atomic number but different mass number
(b) they have same number of electrons but different number of neutrons
(c) they have same number of neutrons but different number of electrons
(d) sum of the number of protons and neutrons is same but the number of protons is
different
different
11
1513Give graph is of which orbital?
A ( .2 p )
в. 1 .
( c .2 s )
( 0.3 s )
11
151479. The circumference of the second Bohr orbit of electron
in hydrogen atom is 600 nm. The potential difference that
must be applied between the plates so that the electrons
have the de Broglie wavelength corresponding in this
circumference is
(a) 10-v
(b) 2 x 10-V
(c) 5 x 10-sv (d) 3 x 10-5 v
11
1515Bohr’s model of an atom is contradicted
by:
A. Paulis exclusive principle
B. Plancks quantum theory
c. Heisenbergs uncertainty principle
D. all the above
11
1516Argon and calcium are isobar. Why?
A. Both have same atomic number equal to 40
B. Both have different atomic mass
C. Both have same atomic mass equal to 40
D. None of above
11
1517The value of Planck’s constant is
( 6.63 times 10^{-34} J-s . ) The velocity of light
is ( 3 times 10^{8} m / ) sec. Which value is closest
to the wavelength in nanometer of a
quantum of light with frequency of ( 8 times ) ( 10^{15} s e c^{-1} ? )
A ( .5 times 10^{-18} )
B . ( 4 times 10^{1} )
( c cdot 3 times 10^{7} )
D. ( 2 times 10^{-25} )
11
1518The energy of an electron in the ( n^{t h} ) Bohr orbit of hydrogen atom is:
A ( cdot frac{13.6}{n^{3}} e V )
В. ( -frac{13.6}{n^{3}} e V )
c. ( -frac{13.6}{n^{2}} e V )
D. ( -frac{13.6}{n} e V )
11
1519The colour of sky is due to:
A. transmission of light
B. wavelength of scattered light
C. absorption of light by atmospheric gases
D. all of these
11
1520The elements ( ^{30} boldsymbol{S} boldsymbol{i}_{14},^{31} boldsymbol{P}_{15} ) and ( ^{32} boldsymbol{S}_{16} ) are
called :
( A ). isotones
B. isobars
c. isotopes
D. mirror nuclei
11
1521The atoms of various isotopes of a particular element differ from each other in the number of:
A. electrons in the outer shell only
B. protons in the nucleus
c. electrons in the inner shell only
D. neutrons in the nucleus
11
1522Kinetic energy of photoelectrons
increases with increase in freqency of the light incident on the metal surface.
A. True
B. False
11
1523Atomic number of Bismuth is:
( A cdot 84 )
B. 85 5
( c cdot 83 )
D. 82
11
1524Estimate the difference in energy between I and II Bohr Orbit for a
hydrogen atom. At what minimum at no a transition from ( n=2 ) to ( n=1 ) energy level would result in the emission of X-rays with ( lambda=3.0 x 10^{8} ) m? Which hydrogen
like species does this at no correspond
to
11
1525In astronomical observations, signals observed from the distant stars are
generally weak. If the photon detector receives a total of ( 3.15 times 10^{-18} J ) from
the radiations of ( 600 mathrm{nm}, ) calculate the number of photons received by the detector.
11
1526( X ) is defined by the number of protons. What is ( X ? )
A. Cation
B. Inert Gas
c. crystal
D. Anion
E . Element
11
1527The state or phase of a given set of matter can change depending on
A. temperature
B. pressure
c. Both a and ( b )
D. None of above
11
1528Calculate the wavelength of the first number of Balmer series of hydrogen spectrum (R for hydrogen ( =1.09678 times 10 ) ( left.7 m^{-1}right) )
A ( cdot 2188 times 10^{-10} mathrm{m} )
B. 656 ( times 10^{-10} mathrm{m} )
c. ( 6564 times 10^{-10} mathrm{m} )
D. None of these
11
1529What is the wavelength (in ( n m ) ) of gamma-rays whose energy is 1.50 eV?
A. ( 827.5 mathrm{nm} )
В. 627.5 nm
c. ( 927.5 mathrm{nm} )
D. None of these
11
1530Which of the following combinations give finally an isotope of the parent element?
A. ( alpha, alpha, beta )
в. ( alpha, gamma, alpha )
c. ( alpha, beta, beta )
( mathbf{D} cdot beta, gamma, alpha )
11
1531If an atom contains one electron and
one proton, what charge will it carry?
A. Positive
B. Neutral
c. Negative
D. All of the above
11
which has no mass??
A. Alpha particle
B. Beta particle
c. Proton
D. Neutron
E. Gamma ray
11
1533Which is not a correct order of energy
for 1 st, 2 nd and 3 rd orbit?
( mathbf{A} cdot E_{1}>E_{2}>E_{3} )
( mathbf{B} cdot(P E)_{1}<(P E)_{2}(K E)_{2}>(K E)_{3} )
D. A and C both
11
1534Which of the following electron transitions in hydrogen atom will require largest amount of energy?
A. From ( n=1 ) to ( n=2 )
B. From ( n=2 ) to ( n=3 )
c. From ( n=infty ) to ( n=1 )
D. From ( n=3 ) to ( n=5 )
11
1535The work function for a certain metal is
4.2 eV. Will this metal give photoelectric emission for incident radiation of
wavelength 330 nm?
11
1536The chloride of a solid metallic element
contains ( 57.89 % ) by mass of the element. The specific heat of the element is 0.0324 cal ( d e g^{-1} g^{-1} )
Calculate the exact atomic mass of the
element.
11
15371. Cathode rays are deflected by
(a) electric field only
(c) magnetic field only
(b) electric and magnetic field
(d) none of these
11
1538If one were to apply Bohr model to a
particle of mass ‘ ( m^{prime} ) and charge ( ^{prime} q^{prime} ) moving in a plane under the influence of
a magnetic field ( B ), the energy of the
charged particle in the ( n^{t h} ) level will be:
( ^{A} cdot nleft(frac{h q B}{8 pi m}right) )
в. ( nleft(frac{h q B}{4 pi m}right) )
c. ( nleft(frac{h q B}{2 pi m}right) )
D. ( nleft(frac{h q B}{pi m}right) )
11
1539The energy required to break one mole
of ( C l-C l ) bond in ( C l_{2} ) in
( 242 k J ) mol ( ^{-1} . ) The longest wavelength
of light capable of breaking a single ( C l-C l ) bond is:
( left[c=3 times 10^{4} m s^{-1} text {and } N_{A}=6.02 timesright. )
( left.10^{23} m o l^{-1}right] )
A. 594 nm
B. 640 nm
c. 700 nm
D. 494 nm
11
1540Assertion
The specific charge of canal rays is not
constant.
Reason
The mass of ion varies with speed.
A. Assertion is correct but Reason is wrong.
B. Assertion is wrong but Reason is correct.
C. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
D. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
11
1541Statement 1
The wavelenght equivalent of ( 1 mathrm{eV} ) is ( 1.24 times 10^{-6} ) metre
and
Statement 2:
Electron volt is the energy imparted to an electron accelerated by a potential
difference of 1 volt.
A. Statement 1 is True, Statement 2 is True; statement 2 is correct explanation for statement 1
B. Statement 1 is True, Statement 2 is True; statement 2 is not a correct explanation for statement 1
c. Statement 1 is True, Statement 2 is False
D. Statement 1 is False, Statement 2 is True
11
1542Total energy of an electron in an atom is
A. less than zero
B. more than zero
c. may be less or more than zero
D. none of the above
11
1543The angular momentum of an electron depends on:
A. principal quantum number
B. azimuthal quantum number
c. magnetic quantum number
D. all of the above
11
1544Electrons are ejected from the metal when a light of certain frequency strikes the surface of a metal, This phenomenon is known as photoelectric effect and the ejected electrons are called photoelectrons.

If true then type ( 1, ) if false then type 0

11
1545Assertion
Cathode rays are deflected towards positive plate in an electric field.
Reason
These consist of negatively charged
particles.
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
11
1546The minimum angular momentum that can be possessed by an electron in a hydrogen atom is:
A ( cdot 2 times 10^{-34} operatorname{kg} m^{2} s^{-1} )
B. ( 1 times 10^{-34} mathrm{gm}^{2} mathrm{s}^{-1} )
C . ( 1 times 10^{-34} mathrm{kgm}^{2} mathrm{s}^{-1} )
D. none of these
11
1547What is the mass of photon of sodium light having a wavelength of 5890 , i? ( left(text { Given } h=6.6 times 10^{-27} text {erg }-text { sec }right) )
( mathbf{A} cdot 3.735 times 10^{-29} g )
В. ( 3.735 times 10^{-33} g )
c. ( 1.57 times 10^{-33} g )
D. ( 3.735 times 10^{-31} g )
11
1548An element has an atomic number 20 .
How many electrons will be present in ( boldsymbol{K}, boldsymbol{L}, boldsymbol{M} ) and ( boldsymbol{N} ) shells of its atom?
A .2,8,6,4
в. 2,8,7,3
c. 3,7,7,3
D. 2,8,8,
11
1549Which of the following is true?
A. The electron density in the xy-plane in 3d ( _{x y} ) orbital si
zero
B. The electron densities in the xy and xz-plane in 3d ( _{y z} ) orbital are zero
C. The electron density in the xy-plane in ( 3 d_{x}^{2} ) orbital is
zero
D. Pauli exclusion principle is followed by bosons which have integral spin
11
1550The phenomenon of radioactivity is associated with:
A. decay of nucleus
B. fussion of nucleus
c. emission of electrons or protons
D. rearrangement in the extra nuclear electron
11
1551Assertion
( gamma- ) rays have very high penetrating
power.
Reason
( gamma- ) rays are electromagnetic radiations of high 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. Assertion is incorrect but Reason is correct
11
1552Describe balance of oxygen in the air.11
1553The time in which activity of an element reduces to ( 90 % ) of its original value is:
The half-life period of element is ( 1.4 times )
( 10^{10} ) years.
A ( cdot 2.128 times 10^{9} ) years
B . ( 1.578 times 10^{7} ) years
c. ( 6.954 times 10^{7} ) years
D. none of these
11
1554Which of the following reactions led to the discovery of neutrons?
A ( cdot_{6} C^{14}+_{1} p^{1} rightarrow_{7} N^{14}+_{0} n^{1} )
B. ( _{4} B e^{9}+_{2} H e^{4} rightarrow_{6} C^{12}+_{0} n^{1} )
( mathbf{c} cdot_{5} B^{11}+_{1} D^{2} rightarrow_{6} C^{11}+_{0} n^{1} )
D. ( _{4} B e^{8}+_{2} H e^{4} rightarrow_{6} C^{11}+_{0} n^{1} )
11
1555How many nodal planes are present in
( 4 d_{z^{2}} ? )
( A cdot 2 )
B.
c. zero
D. 3
11
1556Which of the following transitions will involve maximum amount of energy?
A ( . M rightarrow M^{+}+e^{-} )
B. ( M^{-} rightarrow M^{+}+2 e^{-} )
( mathbf{c} cdot M^{2+} rightarrow M^{3+}+e^{-} )
D. ( M^{+} rightarrow M^{2+}+e^{-} )
11
1557The absolute value of charge on the electron was determined by:
A. J.J. Thomson
B. R.A. Millikan
c. Rutherford
11
1558A body of mass 10 mg is moving with a
velocity of ( 100 m s^{-1} . ) The wavelength of
the de Broglie wave associated with it would be
A ( cdot 6.63 times 10^{-7} mathrm{m} )
B. ( 6.63 times 10^{-31} m )
( c cdot 6.63 times 10^{-4} m )
D. ( 6.63 times 10^{-35} m )
11
1559From Bohr’s model, radius of the orbit
and energy of the hydrogen atom are
calculated as:
This question has multiple correct options
A. the radius of the ( 1^{s t} ) orbit is ( 0.529 A^{circ} )
B. the energy of the ( 1^{s t} ) orbit is ( -13.6 e V )
C. the energy of the ( 1^{s t} ) orbit is ( -21.72 times 10^{-19} J )
D. the radius of the ( 1^{s t} ) orbit is ( 1.06 A^{circ} )
11
1560Arrange the following orbitals in the order in which they are filled with
electrons.
( 6 s, 5 d, 6 p, 7 s, 5 f )
A. ( 6 s<5 d<6 p<7 s<5 f )
B. ( 6 s<6 d<5 d<5 f<7 s )
c. ( 6 d<5 f<6 s<6 p<7 s )
D. ( 6 s<7 s<5 d<5 f<6 p )
11
1561The emission of beta particles is from:
A. the valence shell of an atom
B. the inner shell of an atom
C. the nucleus due to the nuclear conversion proton ( rightarrow ) neutron + electron
D. the nucleus due to the nuclear conversion neutron ( rightarrow ) proton + electron
11
1562The energy of an electron in the first Bohr orbit of H atom is -13.6 eV. The
possible energy value of the excited state for the electron in Bohr orbits of
hydrogen is:
A. -3.4 eV
B. 4.2 eV
( mathbf{c} .-6.8 mathrm{eV} )
D. ( +6.8 mathrm{eV} )
11
1563Which element has a mass number of
20 and contains 11 neutrons??
A. copper
B. Gallium
c. calcium
D. Sodium
E. Fluorine
11
1564Following results are observed when sodium metal is irradiated with different wavelengths. Calculate (a) threshold wavelength and
(b) Plancks
constant.
500
[
lambda(n m)
]
450
( v times 10^{-5}left(mathrm{cms}^{-1}right) ) 2.55 4.35
11
1565Which of these are the characteristics
of wave function ( mathbf{Psi} ? )
This question has multiple correct options
A. ( Psi ) must be single valued
в. ( int_{-infty}^{+infty} Psi^{2} d x d y d z=1 )
c. ( Psi ) must be finite and continous
D. ( Psi ) represents a standing wave
11
1566Which of the following are iso-electronic
species?
A. ( C O_{2}, N O_{2} )
B. ( N O_{2}^{-}, C O_{2} )
c. ( C N^{-}, C O )
D. ( S O_{2}, C O_{2} )
11
1567The number of radial nodes for ( 4 p )
orbital is:
A . 4
B. 3
( c cdot 2 )
D.
11
1568Which of the following sets of quantum numbers represents the 19th electron of ( boldsymbol{C r}(boldsymbol{Z}=mathbf{2 4}) ? )
( ^{mathbf{A}} cdotleft(4,1,-1,+frac{1}{2}right) )
в. ( left(4,0,0,+frac{1}{2}right) )
c. ( left(3,2,0,-frac{1}{2}right) )
D. ( left(3,2,-2,+frac{1}{2}right) )
11
1569What will be the uncertainty in velocity
of a bullet with a mass of ( 10 g ) whose
position is known with ( pm 0.01 mathrm{mm} ) ?
11
1570Concept of stationary orbit was introduced by :
A. Bohr
B. Rutherford
c. Sommerfeld
D. Thomson
11
1571The energy required to break one mole
of hydrogen-hydrogen bonds in ( H_{2} ) is ( 436 k J . ) What is the longest wavelength
of light required to break a single hydrogen-hydrogen bond?
A ( .68 .5 mathrm{nm} )
в. 137 пт
( c .274 n m )
D. 548 пт
11
1572The number of unpaired electrons in a
chromic ion ( left.C r^{+3} text {(atomic number } 24right) )
is:
( A cdot 6 )
B. 4
( c cdot 3 )
D.
11
1573The ratio of the difference in energy
between the first and second Bohr orbit
to that between second and third Bohr
in H-atom is:
( A cdot 4 / 9 )
B. ( 1 / 3 )
c. ( 27 / 5 )
D. ( 1 / 2 )
11
1574Total number of nodes present in ( 4 d^{-} ) orbitals will be
( mathbf{A} cdot mathbf{3} )
B . 2
c. 1
D. 0
11
1575Explanation of the presence of three unpaired electrons in nitrogen atom is given by:
A. Pauli’s principle
B. Hund’s rule
c. Aufbau principle
D. Uncertainty principle
11
1576Quantum number ( (n=3) ) has:
A. s, p electrons
B. s, p, d, electrons
c. s electrons
D. s,p,d,f electrons
11
1577Assertion
The mass spectrometer is used for determination of the atomic mass of
isotopes.
Reason
Isotopes are the atoms of the same element having a same atomic number but different mass numbers
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 incorrect but Reason is correct
D. Both Assertion and Reason are incorrect
11
1578What is the maximum number of
emission lines when the excited
electron of ( mathrm{H} ) atom in ( mathrm{n}=6 ) drops to the ground state?
11
1579According to Bohr’s theory, the energy required for the transition of H-atom from ( n=6 ) to ( n=8 ) state is:
A. equal to the energy required for the transition from ( n= ) 5 to ( n=6 ) state
B. larger than the energy required for the transition from ( n=7 ) to ( n=9 ) state
c. less than the energy required for the transition from n ( =7 ) to ( n=9 ) state
D. equal to the energy required for the transition from ( n= ) 7 to ( n=9 ) state
11
1580State True or False.
( 24 t h ) electron in ( C r ) enters in ( 3 d ) -orbital.
A. True
B. False
11
1581CELLUL CICLU On calulot De uericu.
Q62. The quantum numbers of six electrons are given below. Arrange them in order of increasing
energies. If any of these combination (s) has/have the same energy?
(i) n = 4, 1 = 2, m, = -2, m = -1/2
(ii) n = 3,1 = 2, m, = 1, m = + 1/2
(iii)n = 4,1 = 1, m, = 0, m = + 1/2
(iv) n = 3,1 = 2, m, = -2, m, = -1/2
(v) n = 3,1 = 1, m, = -1, m = +1/2 (vi) n = 4, 1 = 1, m, = 0, m = + 1/2
11
1582Assertion
Half-filled and fully-filled degenerate orbitals are more stable.
Reason
Extra stability is due to the symmetrical distribution of electrons
and exchange 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. Assertion is incorrect but Reason is correct
11
1583The nuclear model of the atom was
suggested by:
A. Bohr
B. Rutherford
c. Pauli
D. Mendeleef
11
1584The electron density between ( 1 s ) and ( 2 s )
is:
A . high
B. low
c. zero
D. abnormal
11
1585For an electron with ( n=3 ) has only one
radial node. The orbital angular momentum of the electron will be :
A. 0
B. ( sqrt{6} frac{h}{2 pi} )
c. ( sqrt{2} frac{h}{2 pi} )
D ( cdot 3left(frac{h}{2 pi}right) )
11
1586Assertion
An orbital cannot have more than two
electrons.
Reason
The two electrons in an orbital create
opposite magnetic field.
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
11
1587Calculate the difference in the number
of carbon atoms in 1.0 g of ( C-14 ) isotope and ( 1.0 mathrm{g} ) of ( C-12 ) isotope.
A ( .7 .2 times 10^{21} )
B. ( 6.2 times 10^{20} )
C ( cdot 6.2 times 10^{22} )
D. ( 7.2 times 10^{20} )
11
1588A transition of electron from an higher
orbit to ( 2^{n d} ) orbit produces 10 spectral lines. The higher orbit no. is :
A. seven
B. eight
c. six
D. five
11
1589Energy associated with an orbit as its distance increases from the
nucleus.
A. increases
B. decreases
c. no relation
D. may increase or decrease depending on distance from the nearest orbit
11
1590When photons of energy ( 4.25 e V ) strike
the surface of a metal ( A ), the ejected
photo-electrons have maximum kinetic
energy, ( boldsymbol{T}_{A}(text { expresses in } boldsymbol{e} boldsymbol{V}) ) and de
Broglie wavelength ( lambda_{A} ). The maximum
kinetic energy of photoelectrons liberated from another metal ( B ) by
photons of energy ( 4.70 e V ) is ( T_{B}=T_{A}- )
1.50 ( e V ). If the de-Broglie wavelength of
these photo-electrons is ( lambda_{B}=2 lambda_{A}, ) then
which is not correct?
A. The work function of ( A ) is ( 2.25 e V )
B. The work function of ( B ) is ( 1.20 e V )
( mathbf{c} cdot T_{A}=2.00 e V )
D. ( T_{B}=0.5 e V )
11
1591A plot of kinetic energy of the emitted electron against frequency of the incident radiation yields a straight line. The slope of the straight line is:
A. ( 0.66 times 10^{-35} )
В. ( 0.66 times 10^{-33} )
c. ( 0.33 times 10^{-33} )
D. ( 3.33 times 10^{-35} )
11
1592Which of the following properties can only be a whole number?
A. Atomic mass
B. Atomic volume
D. Mass number
11
1593Not considering the electronic spin, the degeneracy of the second excited state
( (n=3) ) of ( H ) -atom is ( 9, ) while the
degeneracy of the second excited state
of ( boldsymbol{H}^{-} ) is
11
1594What are the total number of orbitals
and electrons for ( m=0, ) if there are 30 protons in an atom?
A. 6 orbitals, 12 electrons
B. 5 orbitals, 10 electrons
c. 7 orbitals, 14 electrons
D. 4 orbitals, 8 electrons
11
1595If ( Z ) is the atomic number of a one-
electron species and ( n ) is the orbit in which the electron is revolving, show that the number of revolutions made by
the electron in that orbit in 1 second
times is directly proportional to ( frac{Z^{2}}{n^{3}} )
11
1596Calculate the uncertainly is the positive of dust particle with mass equal to Img.ln uncertainly in velocity is ( 5.5 times ) ( mathbf{1 0}^{-mathbf{2 0}} boldsymbol{m} / boldsymbol{s} )11
1597The is the smallest unit of matter.
A. Element
B. Atom
c. Molecule
D. Electron
11
1598What will be the wavelength of an
electron moving with ( frac{1}{10} t h ) of velocity of light?
A ( cdot 2.43 times 10^{-11} mathrm{m} )
В . ( 243 times 10^{-11} ) и
( c .0 .243 m )
D. 2.43 ( times 10^{-4} mathrm{m} )
11
1599( ln Psi_{321} ) the sum of angular momentum, spherical nodes and angular mode is:
A ( cdot frac{sqrt{6 h}+4 pi}{2 pi} )
в. ( frac{sqrt{6 h}}{2 pi}+3 )
c. ( frac{sqrt{6 h}+2 pi}{2 pi} )
D. ( frac{sqrt{6 h}+8 pi}{2 pi} )
11
1600The angular momentum of an electron present in the excited state of Hydrogen is ( frac{1.5 h}{pi} . ) The electron is present in:
A. third orbit
B. second orbit
c. fourth orbit
D. fifth orbit
11
1601If the threshold wavelength ( left(lambda_{0}right) ) for the
ejection of an electron from metal is ( 330 mathrm{nm}, ) then work function for the photoelectric emission is:
B. ( 1.2 times 10^{-20} ) 」
D. ( 6 times 10^{-12} ) J
11
1602If the radius of the hydrogen atom is 53 ( mathrm{pm}, ) the radius of the ( H e^{+} ) ion is closest
to:
A ( .108 mathrm{pm} )
B. ( 81 mathrm{pm} )
c. 27 pm
D. 13 pm
11
1603Calculate the wavelength of an electron
moving with a velocity of ( 2.05 times ) ( 10^{7} m s^{-1} )
11
1604Select the species which are isoelectronic.
A ( cdot F^{-}, M g^{2+} )
в. ( A r, K )
c. ( M g^{2+}, O^{-} )
D. ( R b^{+}, A r )
11
1605By what factor the velocity of an electron in a Bohr’s orbit for a hydrogen atom will change, if the principal quantum number is doubled:
A. velocity is doubled
B. velocity is halved
C . velocity is reduced to ( frac{1}{3} )
D. velocity remains unchanged
11
1606The wavelength of the radiation emitted
when an electron falls from Bohr orbit 4
to 2 in hydrogen atom is:
A . 243 nm
В. 972 пт
c. 486 пт
D. 182 nm
11
1607Find number of protons and neutrons
for ( (a),(b) ) and ( (c) ) respectively.
(a) ( _{17}^{35} C l(b)_{6}^{12} C(c)_{35}^{81} B r )
( A cdot n_{p}=17,6,35 )
( n_{n}=18,6,46 )
B . ( n_{p}=16,6,35 )
( n_{n}=18,6,46 )
( c cdot n_{p}=17,6,35 )
( n_{n}=18,6,45 )
D ( . n_{p}=16,6,35 )
( n_{n}=18,6,45 )
11
1608The percentage of an element ( M ) is 53 percentage in its oxide of molecular
formula ( M_{2} O_{3} ). Its atomic mass is
A . 45
B. 9
( c cdot 18 )
D. 38
E. 27
11
1609Select the correct statement.
A. The charge to mass ratio of the particles in anode rays depend on the gas present in the tube
B. Behavior of cathode rays particle and anode rays particle are same in presence of magnetic field (in terms of extent of deviations)
C. Cathode and anode rays start from cathode and anode respectively
D. The charge to mass ratio of the particle in cathode rays depends on the voltage applied across the terminal
11
161036. Alpha particle is the nucleus of
an atom of
(1) Lithium (2) Hydrogen
(3) Helium (4) Oxygen
11
1611The work function of a metal is ( 4.2 mathrm{eV} ). If
radiation of ( 2000 A^{circ} ) falls on the metal,
the kinetic energy of the fastest photoelectron is:
A . ( 1.6 times 10^{-19} mathrm{J} )
В. ( 16 times 10^{-10} J )
c. ( 3.2 times 10^{-19} mathrm{J} )
D. ( 6.4 times 10^{-10} mathrm{J} )
11
1612Calculate the energy associated with
the first orbit of ( H e^{+} . ) What is the
11
1613An isotone of ( _{32}^{76} ) Ge is :
( A cdot_{34}^{78} S e )
( mathrm{c} cdot frac{78}{33} mathrm{Se} )
D. ( frac{77}{32} ) Ge
11
1614Which of this have same chemical
properties, but their physical properties may be different?
A. Atomic number
B. Mass number
c. Isotopes
D. Isobars
11
1615Which of following was not explained by Rutherford?
A. Arrangement of electrons around the nucleus
B. Arrangement of protons
c. Arrangement of nuetrons
D. None of the above
11
1616State True or False.
The magnetic quantum number gives the orientation of electron clouds with
respect to external magnetic field.
A . True
B. False
11
1617Draw the geometrical representation of the atom of the element ( _{8}^{16} boldsymbol{O} )11
1618What do you understand by isotopes? Given one example.11
1619Q30. From the following sets of quantum numbers, state which are possible. Explain why the others
are not possible.
(i) n= 0,1 = 0, m, = 0, m = + 1/2 (ii) n= 1, 1 = 0, m = 0, m = -1/2
(iii) n = 1, 1 = 1, m, = 0, m = + 1/2 (iv) n = 1,1 = 0, m, = + 1, m = + 1/2
(v) n = 3,1 = 3, m, = -3, m = + 1/2 (vi) n = 3,1 = 1, m, = 0, m = + 1/2
11
1620Give the number of neutrons in an atom
of the isotope ( _{47}^{107} A g )
A . 59
B. 60
( c .61 )
D. 58
11
1621Light of frequency ( 7.21 times 10^{14} H z ) is
incident on a metal surface. Electrons
with a maximum speed of ( 6.0 times )
( 10^{5} m / s ) are ejected from the surface.
What is the threshold frequency for photoemission of electrons?
11
1622A ( 1-k W ) radio transmitter operates at a
frequency of 880 Hz. How many photons per second does it emit?
A. ( 1.71 times 10^{21} )
the ( 1.71 times 10^{1.11} )
B . ( 1.71 times 10^{30} )
c. ( 6.02 times 10^{23} )
D. ( 2.85 times 10^{26} )
11
1623Which of the following properties is
different for neutral atoms of the
isotopes of the same element?
A. Atomic number
B. Mass
c. Number of electrons
D. General chemical reactions
11
1624The density of nucleus is of the order of:
A ( cdot 10^{5} k g m^{-3} )
В. ( 10^{16} ) kgm ( ^{-3} )
( mathbf{c} cdot 10^{17} k g m^{-3} )
D. ( 10^{25} mathrm{kgm}^{-3} )
11
1625List three rules for the linear
combination of atomic orbitals.
11
1626Assertion
Proton, electron and neutron each has its antiparticle.
Reason
Antiproton and antielectron has
opposite charge to proton and electron are called antiproton and positron
respectively. Antineutron possess only opposite spin.
A. Assertion is correct but Reason is wrong
B. Assertion is wrong but Reason is correct
C. Both Assertion and Reason are correct and Reason is correct explanation of Assertion
D. Both Assertion and Reason are correct but Reason is not correct explanation of Assertion
11
1627A d-block element has total spin value
of ( +3 . ) Then, the spin only magnetic moment of the element is
approximately:
A. 2.83 В.M.
B. 3.87 В.М.
c. 5.9 в.М
D. 6.93 В.М.
11
1628Q11. What do you understand by isoelectronic species? Name a species that will be isoelectronic
with each of the following atoms or ions.
(i) F (ii) Ar (ii) Mg** (iv) Rb
bar
11
1629In which of the following transformations, the ( beta ) -particles are
emitted?
A. Proton to neutron
B. Neutron to proton
c. Proton to proton
D. Neutron to neutron
11
1630Values of magnetic orbital quantum number for an electron of ( M ) -shell can
be:
( mathbf{A} cdot 0,1,2 )
в. -2,-1,0,+1,+2
c. 0,1,2,3
D. -1,0,+1
11
1631How many ( d ) -electrons in ( C u^{+} ) (Atomic
number ( =29 ) ) can have the spin quantum number ( left(-frac{1}{2}right) ? )
( A cdot 3 )
B. 7
( c .5 )
D.
11
1632( M g^{2+}, A l^{3+} ) have identical:
A. configuration
B. atoms
( c . ) ions
D. molecules
11
1633Calculate the energy of photon of light
having frequency ( 3 times 10^{5} ) Hz. If wavelength of light is ( lambda(0.50 A A), ) then
calculate its energy.
11
1634Which of the following has two or more same electronic configuration?
This question has multiple correct options
A. Allotropes
B. Amphiprotic
c. Isoelectronic
D. Isomers
E. Isotopes
11
1635Which transition emits photon of
maximum frequency?
A. 2 nd spectral line of Balmer series
B. 2nd spectral line of Paschen series
C. 5 th spectral line of Humphery series
D. 1 st spectral line of Lyman series
11
1636The fractional abundance of ( C l^{35} ) in a
sample of chlorine containing only ( C l^{35} ) (atomic weight ( =mathbf{3 4 . 9} ) ) and ( boldsymbol{C l}^{mathbf{3 7}} )
(atomic weight ( =mathbf{3 6 . 9} ) ) isotopes, is ( mathbf{0 . 6} )
The average mass number of chlorine
is
A . 35.7
B. 35.8
c. 18.8
D. 35.77
11
1637Q. 12 orbita angular momentum depends on cam
Q. 12 Orbital angular momentum depends on ……..
(a) ?
(b) n and 1
(c) n and m
(d) m and s
11
1638The speed of electron revolving in the 4
th orbit of a hydrogen like atom or ion is ( 1094 mathrm{km} / mathrm{s} . ) The atom or ions is:
A. ( H )
в. ( H e^{+} )
( mathrm{c} cdot L i^{2} )
( D cdot B e^{3} )
11
1639In the pictorial representation of an orbital, the role of different intensity of shading is to find the maximum probability of an electron.
A . True
B. False
11
1640The ratio of the difference in energy of
electron between the first and second
Bohr’s orbits to that between second
and third Bohr’s orbits is :
A. ( 1 / 3 )
в. 27/5
( c cdot 9 / 4 )
D. ( 4 / 9 )
11
1641A metalo xide has the formula ( X_{2} O_{3} . ) It
can be reduced by hydrogen to give free metal and water.0.1596 g of metal oxide requires ( 6 mathrm{mg} ) of hydrogen for complete reduction. Calculate the atomic weight of the metal(in amu).
11
1642The wavelength associated with a golf ball weighing ( 200 mathrm{g} ) and moving at a speed of ( 5 m h^{-1} ) is of the order:
B . ( 10^{-20} m )
( mathbf{c} cdot 10^{-30} m )
D. ( 10^{-40} m )
11
1643Bohr modified the adding that the electrons move in orbits
of fixed size and energy.
A. Rutherford’s model
B. Dalton’s model
D. Goldstein’s model
11
1644Which of the following ion is
isoelectronic with ( boldsymbol{O}^{2-} ) ?
This question has multiple correct options
A . ( N^{3-} )
B. ( N^{text {t }} )
( c cdot F^{-} )
D. ( T i^{+} )
11
1645The radius of the first Bohr orbit of hydrogen atom is 0.59 , the radius of
the third orbit of ( boldsymbol{H} boldsymbol{e}^{+} ) will be:
( mathbf{A} cdot 8.46 stackrel{circ}{A} )
в. 0.705 А
( mathbf{c} cdot_{1.59 A}_{A}^{circ} )
D ( cdot 2.38 stackrel{circ}{A} )
11
1646The radius of ( boldsymbol{H}- ) atom in its ground
state is ( 0.53 A^{circ} . ) The radius of ( L i^{2+} ) in
the similar is:
( mathbf{A} cdot 0.058 A^{circ} )
B. ( 0.171 A^{circ} )
c. ( 0.706 A^{circ} )
D. ( 1.06 A^{circ} )
11
1647The sequence of filling electrons in different shells is determined by:
A. Octet rule
B. Hund’s rule
c. Aufbau rule
D. All the above
11
1648For ( n=3 ) energy level, the number of possible orbitals is:
A . 1
B. 3
( c cdot 4 )
D.
11
1649Match the following
Codes:
[
P Q R S
]
(A) 3412
( begin{array}{llll}text { (B) } & 2 & 1 & 3 & 1end{array} )
(Species)
(Relation)
11
1650Which is the correct combination
begin{tabular}{ll|l|l|}
& & multicolumn{2}{l} { change } \
& & in \
Emission & Atomic number & mass number \
hline (a) & ( alpha ) & -2 & -2 \
(b) & ( beta^{-} ) & +1 & 0 \
(c) & ( gamma ) & 0 & 0 \
(d) & ( beta^{+} ) & -1 & 0 \
hline
end{tabular}
11
1651In a container a mixture is prepared by mixing of three samples of hydrogen, helium ion ( left(H e^{+}right) ) and lithium ion
( left(L i^{2+}right) ) In sample all the hydrogen atoms are in 1 st excited state and al
the He ions are in third excited state
and all the ( left(L i^{2+}right) ) ions are in fifth
excited state Find the total number of
spectral lines observed in the emission
spectrum of such a sample, when the electrons return back upto the ground
state
11
1652Statement ( I:^{12} C )
is an isotope of ( ^{14} boldsymbol{C} )
Statement II :The nuclei of both atoms
have the same number of neutrons.
( mathbf{A} cdot ) true, false
B. false, true
c. false, false
D. true, true, correct explanation
11
1653Assertion
Atoms with completely filled and half filled subshells are stable.
Reason
Completely filled and half-filled subshells have the symmetrical distribution of electrons and have
maximum exchange 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. Assertion is incorrect but Reason is correct
11
1654Symbols ( _{35}^{79} B r ) and ( ^{79} B r ) can be written, whereas symbols ( _{79}^{35} B r ) and ( ^{35} B r ) are not acceptable. Answer briefly:11
1655Number of lobes present in ( d_{z^{2}} ) orbital is
A . 10
B. 5
( c cdot 4 )
D. 2
11
1656The dissociation energy of ( boldsymbol{H}_{2} ) is
( 482.5 K J / ) mol. If ( H_{2} ) is exposed to radiant energy of wavelength ( 124 mathrm{nm} ) what ( % ) of radiant energy will be converted into K.E?
( left(1 frac{e v}{a t o m} 5=96 k J / m o l .right) )
11
1657The ( e / m ) value for cathode rays:
A. varies with the nature of the gas
B. does not vary with the nature of gas
C. could not be determined by J.J Thomson
D. both (b) and (c) are correct
11
1658According to classical theory, if an electron is moving in a circular orbit around the nucleus:
A. it will continue to do so for sometime
B. its orbit will continuously shrink
c. its orbit will continuously enlarge
D. it will continue to do so for all the time
11
1659The potential energy of the electron
present in the ground state of ( L i^{+2} ) ion is represented by:
A ( cdot frac{+3 e^{2}}{4 pi varepsilon_{0} r} )
в. ( frac{-3 e}{4 pi varepsilon_{0} r} )
c. ( frac{-3 e^{2}}{4 pi varepsilon_{0} r} )
D. ( frac{-9 e^{2}}{4 pi varepsilon_{0} r} )
11
1660Find the radius of nucleus of an atom
having atomic mass number equal to
125. ( left(text { Take } boldsymbol{R}_{0}=mathbf{1 . 3} times mathbf{1 0}^{-mathbf{1 5}} boldsymbol{m}right) )
11
1661What is the main difference between
electromagnetic wave theory and
Planck’s quantum theory?
A. According to electromagnetic wave theory, the energy is emitted or absorbed continuously whereas according to Planck’s quantum theory, energy is emitted or absorbed discontinuously,i.e. in certain definite packets called ‘Quanta’
B. According to electromagnetic wave theory, energy is emitted or absorbed discontinuously, i.e., in certain definite packets called ‘Quanta’ whereas according to Planck’s quantum theory, the energy is emitted or absorbed continuously
C. According to electromagnetic wave theory, the energy is emitted or absorbed continuously whereas according to Planck’s quantum theory, energy is emitted or absorbed continuously,i.e. in certain definite packets called ‘Quanta’
D. According to electromagnetic wave theory, the energy is emitted or absorbed discretely whereas according to Planck’s quantum theory, energy is emitted or absorbed discontinuously, i.e., in certain definite packets called’Quanta’
11
1662Match the following11
1663A neutral atom of an element has ( 2 mathrm{K}, 8 mathrm{L} )
and ( 5 mathrm{M} ) electrons. What is the total
number of unpaired electrons?
( A cdot 2 )
B. 3
( c cdot 4 )
D. 5
11
1664The frequency of ( e^{-} ) in the first Bohr orbit in a H-atom is:
A. ( 6530 times 10^{12} mathrm{Hz} )
В. ( 6840 times 10^{12} mathrm{Hz} )
c. ( 6430 times 10^{12} mathrm{Hz} )
D. ( 6734 times 10^{12} mathrm{Hz} )
11
1665Number of neutrons in a parent nucleus ( X, ) which gives ( _{7}^{14} mathrm{N} ) after two
successive ( beta ) -emission would be :
( A cdot 6 )
B. 7
( c cdot 8 )
D.
11
1666Rutherford’s model was not able to
explain:
A. Rebounding of alpha particles
B. Deflection of aplha particles
c. concentration of positive charge at centre
D. Line spectra of Atom
11
1667Angular and spherical nodes in ( 3 s ) is:
A . ( 1, )
в. 1,0
( c cdot 2,0 )
D. 0,2
11
1668The number of nodes in ( 3 p ) orbital are :11
1669What is likely to be orbit number for a
circular orbit of diameter 20 nm of the hydrogen atom?
A . 10
B. 14
c. 12
D. 16
11
1670Q2. What is the minimum product of uncertainty in position and momentum of an electron?
Ane bo
11
1671Identify the following elements.
a) ( _{25} X^{55} )
b) ( _{17} X^{35} )
c) ( _{20} X^{40} )
11
1672Circumference of the first orbit of
hydrogen atom is given by the formula:
( left[a_{0}=frac{h^{2}}{4 pi^{2} m e^{2}}right] )
A ( cdot frac{22}{7} a )
в. ( frac{pi a_{0}}{2} )
c. ( sqrt{4} pi a_{0} )
D. ( pi a_{0} )
11
1673State True or False.
Thomson discovered isotopes.
A. True
B. False
11
1674The following charged particles accelerated from rest, through the same potential difference, are projected towards gold nucleus in different experiments. The distance of closest
approach will be maximum for
A. ( alpha ) -particles
B. proton
c. deuteron
D. neutron
11
1675Which of the following is incorrect?
A. Hydrogen > Deuterium > Tritium; (% relative abundance)
B. Hydrogen < Deuterium < Tritium; (density/g ( L^{-1} ) )
C. Hydrogen < Deuterium < Tritium; (boiling point/K)
D. Hydrogen Tritium; (melting point/K)
11
1676Which of the following is an isoelectronic pair?
A ( cdot K^{+}, C l^{-} )
В. ( N a^{+}, C l^{-} )
( mathbf{c} cdot N a^{+}, H e )
D. ( H^{+}, X e )
11
1677The entire positive charge of the atom is located in the nucleus while the
electrons are distributed in the vacant
space around it. This statement was
given by Thomson.
A. True
B. False
11
1678State whether the given statement is true or false:

With the increase in distance from the
nucleus, energy of electron increases and the velocity of electron decreases.
A. True
B. False

11
1679Radiation of wavelength 242 nm is
sufficient to ionize the sodium atom.
Calculate the ionization energy in
( boldsymbol{k J} boldsymbol{m o l}^{-1} cdotleft(boldsymbol{n}=mathbf{6 . 6 2 5} times mathbf{1 0}^{-mathbf{3 4}} boldsymbol{J}-boldsymbol{s}right) )
A. ( 493.6 k J )
( J )
B . ( 6.625 times 10^{3} J )
c. ( 242 k J )
D. ( 1324 k J )
11
1680An electron in the hydrogen atom is excited from ( 1^{s t} ) orbit to ( 5^{t h} ) orbit. Find
the change in energy of the electron in
( e V: )
A. (13.6 ( times 24) / 25 )
B. (13.6 ( times 4) / 5 )
( c cdot(0.529 times 4) / 5 )
D. (13.6 ( times 4) / 9 )
11
1681Which of the following statements is
A. Isotopes have same number of electrons
B. Isotopes have same chemical properties
C. Isotopes have same number of neutrons
D. Isotopes have same number of protons
11
1682The molar mass of ( N_{2} O ) as well as ( C O_{2} )
is ( 44 g m o l^{-1} . A t 25^{o} C ) and 1 atm
pressure, ( 1 mathrm{L} N_{2} mathrm{O} ) contains ( mathrm{n} ) molecules
of gas. The number of ( C O_{2} ) molecules in
2 L under same conditions will be:
( A )
B. ( 2 n )
( c cdot frac{n}{2} )
( D cdot frac{n}{n} )
11
1683State True or False.
The radial wave function for the ground state of ( H ) -atom decreases
exponentially towards zero as ( r )
increases.
A. True
B. False
11
1684The de Broglie wavelength of a particle with mass ( 1 mathrm{gm} ) and velocity ( 100 mathrm{m} / mathrm{s} ) is:
A ( cdot 6.63 times 10^{-33} m )
B. ( 6.63 times 10^{-34} m )
D. ( 6.635 times 10^{-35} m )
11
1685How many ‘alpha’ and’ ( beta ) ‘-particles will be emitted when ( _{90} T h^{234} ) changes into ( 84 P o^{218} ? )11
1686The electronic configuration of valence
shell of ( C u ) is:
A ( cdot 3 d^{10} 4 s^{2} )
B. ( 3 d^{9} 9 s^{2} )
( mathbf{c} cdot 3 d^{10} 4 s )
D. ( 3 d^{10} 4 s^{0} )
11
1687Which of the following can be negative?
A ( cdot 4 pi r^{2} Psi^{2} )
B . ( 4 pi r^{2} Psi^{2} d r )
( c . Psi )
D. ( Psi^{2} )
11
1688Which of the following is not a permissible arrangement of electrons
in an atom?
A ( cdot n=3,1=2, m=+1, s=-frac{1}{2} )
B ( cdot n=4,1=0, m=0, s=-frac{1}{2} )
( c cdot n=5,1=3, m=0, s=+frac{1}{2} )
D. ( n=3,1=2, m=-3, s=-frac{1}{2} )
11
1689energy increases
15. An electron beam is accelerated by a potential difference
V to hit a metallic target to produce X-rays. It produces
continuous as well as characteristic X-rays. If min is the
smallest possible wavelength of X-ray in the spectrum, the
variation of log 2 min with log Vis correctly represented in
(a) log imin
(b) log 2 min
log v
(c) log Amin
→log V
(d) log Amin
→log V
►log V
(JEE Main 2017)
11
1690H-atom is exposed to electromagnetic radiation of ( lambda=1025.6 A ) and excited
atom gives out induced radiations. What is the minimum wavelength of these induced radiations?
A. ( 102.6 mathrm{nm} )
B. ( 12.09 mathrm{nm} )
c. ( 121.6 mathrm{nm} )
D. ( 810.8 mathrm{nm} )
11
16913. If 5% of the energy supplied to a bulb is irradiated as
visible light, how many quanta are emitted per second
by a 100 W lamp? Assume wavelength of visible light as
5.6 x 10 cm.
(a) 1.4 x 1019
(b) 3 x 103
(c) 1.4 x 10-19 (d) 3 x 104
11
1692The nature of anode rays depends upon:
A. nature of gas filled in the discharge tube
B. nature of electrode
c. nature of metal
D. none of these
11
1693Thomson proposed that:
A. an atom consists of a positively charged sphere and the electrons are embedded in it.
B. the negative and positive charges are equal in magnitude. So that atoms as a whole are electrically neutral.
( c . ) both ( A ) and ( B )
D. none of the above.
11
1694Which of the following is correctly matched?
A. Momentum of H-atom when electrons return from
( n=2 ) to ( n=1: frac{3 R h}{4} )
B. Momentum of proton: Independent of wavelength of light
c. e/m ratio of anode rays : Independent of gas in the discharge tube
D. Radius of nucleus :: (Mass no.) ( ^{1 / 2} )
11
1695What is the ratio of mass for ( alpha ) and
neutron particles?
A .1: 16
B. 16: 1
( c cdot 4: )
D. 1: 4
11
1696Multiple of fine structure of spectral
lines is due to:
A. presence of main energy levels
B. presence of sub-level
c. presence of electronic configuration
D. is not a characteristics of the atom.
11
1697( pi^{o} ) meson is exchanged between:
A. proton and neutron
B. proton and proton
c. neutron and neutron
D. may be between two protons or two neutrons
11
1698( boldsymbol{K}^{+}, boldsymbol{A} boldsymbol{r}, boldsymbol{C l}^{-} ) are iso electronic species
A. True
B. False
11
1699( frac{h}{2 pi} ) is angular momentum in orbit of ( boldsymbol{H} boldsymbol{e}^{+} )
A . first
B. second
c. third
D. infinite
11
1700Mirror nuclei are those which have:
A. the same number of protons
B. the same number of neutrons
C. the number of protons equal to number of neutrons
D. the number of neutrons in one equal to the number of protons in the other
11
1701The charge to mass ratio is highest for:
A. proton
B. electron
c. neutron
D. alpha
11
1702The wave number of the ( H_{alpha} ) -line in
Balmer series of hydrogen spectrum is :
A . 5R / 36
в. зв
c. ( 21 mathrm{R} / 100 )
D. 3R / 4
11
1703Which one of the following statements
is correct?
A. 2 s orbital is spherical with two nodal planes
B. The de Broglie wavelength ( ( lambda ) ) of a particle of mass ‘m’ and velocity ‘V’ is equal to mV/h
C. The principal qantum number (n) indicates the shape of the orbital
D. The electronic configuration of phosphorous is given by [Ne] ( 3 s^{2} 3 p_{x}^{1} 3 p_{y}^{1} 3 p_{z}^{1} )
11
1704040. In Rutherford experiment, generally the thin foil of heavy atoms like gold, platinum etc., have
been used to be bombarded by the a-particles. If a thin foil of light atoms like aluminium etc.,
is used, what difference would be observed from the above results?
1-alane amount of nocito b
uone
11
1705According to Thomson, an atom consists of :
A. embedded electrons
B. positively charged uniform sphere
c. positively charged nucleus
D. both a and
11
1706Q26. An atom of an element contains 29 electrons and 35 neutrons. Deduce (1) the number of
protons and (ii) the electronic configuration of the element.
Ans. No of proton
11
1707According to Bohr’s theory of hydrogen atom, the product of the binding energy of the electron in ( n^{t h} ) orbit and the
radius of the ( n^{t h} ) orbit :
A . is proportional to ( n^{2} )
B . is inversely proportional to ( n^{3} )
c. has a constant value of ( 10.2 e V A^{0} )
D. has a constant value of ( 7.2 e V A^{0} )
11
1708p-subshell can accommodate a maximum of how many electrons?
A. 6
B. 8
( c cdot 4 )
( D )
11
1709In a hydrogen atom, the electronjumps from 3 to 2 energy level, the energy released is:
A ( cdot 3.03 times 10^{-19} ) Jatom ( ^{-1} )
В. ( 1.03 times 10^{-19} ) Jatom( ^{-1} )
c. ( 3.03 times 10^{-18} ) Jatom ( ^{-1} )
D. ( 6.06 times 10^{-19} ) Jatom ( ^{-1} )
11
1710The radial part of wave function
depends on the quantum numbers:
This question has multiple correct options
( A )
B.
( c cdot mid, m_{1} )
D. nonly
11
1711Transformation of uranium-238 into
thorium-234 is done by the process:
A. gamma decay
B. nuclear fusion
c. alpha decay
D. positron emission
E. nuclear fission
11
1712As per de Broglie’s formula a
macroscopic particle of mass ( 100 g ) and
moving at a velocity of ( 100 mathrm{cm} s^{-1} ) will have a wavelength of :
A ( cdot 6.6 times 10^{-29} mathrm{cm} )
B . ( 6.6 times 10^{-30} mathrm{cm} )
c. ( 6.6 times 10^{-31} mathrm{cm} )
D. ( 6.6 times 10^{-32} mathrm{cm} )
11
1713According to Bohr’s theory, the angular momentum for an electron of 5th orbit
is:
( mathbf{A} cdot 10 h / pi )
в. ( 5 h / 2 pi )
( mathbf{c} cdot 25 h / pi )
D. ( 5 pi / 2 h )
11
1714How can an element be defined as
consisting of any mixture of atoms with a given atomic number?
A. Determines the mass of of element in the mixture
B. Determines the chemical properties of an element
c. Both A and B
D. None of the above
11
1715( mathbf{Psi}^{2}=mathbf{0} ) represents:
A . a node
B. an orbital
c. angular wave function
D. wave function
11
1716What is meant by imperfect sheilding of
( e^{-} ) by the nucleus?
11
1717<