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

#### List of kinetic theory Questions

Question No | Questions | Class |
---|---|---|

1 | The average kinetic energy of the molecules of an ideal gas at ( 10^{circ} mathrm{C} ) has the value E. The temperature at which the kinetic energy of the same gas becomes ( 2 mathrm{E} ) is ( mathbf{A} cdot 5^{circ} C ) В ( cdot 10^{circ} mathrm{C} ) ( c cdot 40^{circ} C ) D. None of these | 11 |

2 | If ( triangle E ) is the heat of reaction for ( C_{2} H_{3} O H_{(1)}+3 O_{2(g)} rightarrow 2 C O_{2(s)}+ ) ( mathbf{3} boldsymbol{H}_{2} mathbf{0}_{(1)} ) at constant volume, the ( triangle boldsymbol{H} ) Heat of reaction at constant pressure) at constant temperature is: A ( . triangle H=triangle E+2 R T ) B. ( triangle H=triangle E-2 R T ) c. ( triangle H=Delta E+R T ) D. ( triangle H=triangle E-R T ) | 11 |

3 | How many degrees of freedom are associated with 2grams of He at NTP? A. 3 B. ( 3.01 times 10^{23} ) c. ( 9.03 times 10^{23} ) D. 6 | 11 |

4 | The mass of a gas molecules is ( 4 times 10^{-30} mathrm{kg} ) If ( 10^{23} ) molecules strike per second at ( 4 mathrm{m}^{2} ) area with a velocity ( 10^{7} mathrm{m} / mathrm{s} ), then the pressure exerted on the surface will be A. 1 Pascal B. 3 Pascal c. 2 Pascal D. 4 Pascal | 11 |

5 | A monoatomic ideal gas ( left(C_{V}=frac{3}{2} Rright) ) is allowed to expand adiabatically and reversibly from initial volume of ( 8 mathrm{L} ) at ( 300 mathrm{K} ) to a volume of ( V_{2} ) at ( 250 mathrm{K} . V_{2} ) is: (Given ( left.(4.8)^{1 / 2}=2.2right) ) A . ( 10.5 mathrm{L} ) B. 23 L ( c .8 .5 ) D. 50.5 | 11 |

6 | Assertion STATEMENT-1 The total translational kinetic energy of all the molecules of a given mass of an ideal gas is 1.5 times the product of its pressure and its volume Reason STATEMENT-2 The molecules of a gas collide with each other and the velocities of the molecules change due to the collision. A. Statement-1 is True, Statement-2 is True; Statement- is a correct explanation for Statement- – B. Statement- – is True, Statement-2 is True; Statement-2 is NOT a correct explanation for Statement- c. Statement- – 1 is True, Statement- 2 is False D. Statement- – is False, Statement-2 is True | 11 |

7 | A quantity of 10 g of a gas at 1 atm pressure is cooled from ( 273^{circ} mathrm{C} ) to ( 273 mathrm{K} ) keeping its volume constant, the final pressure of the gas will be? A. 273 atm B. 0.5 atm c. 0.2 atm D. 0.1 atm | 11 |

8 | The pressure coefficient of a gas is ( operatorname{(in} /^{0} C ) ): A. 0.00367 в. – -27 ( c . ) 98 D. 3.14 | 11 |

9 | The quantity ( frac{2 U}{f k T} ) represents (where ( U= ) internal energy of gas A. mass of the gas B. kinetic energy of the gas c. number of moles of the gas D. number of molecules in the gas | 11 |

10 | A container is filled with 20 moles of an ideal diatomic gas at absolute temperature ( T . ) When heat is supplied to gas, temperature remains constant but 8 moles dissociate into atoms. Heat energy given to gas is A ( .4 R T ) в. ( 6 R T ) ( c .3 R T ) D. ( 5 R T ) | 11 |

11 | The total kinetic energy of 1 mole of ( N_{2} ) at ( 27 mathrm{C} ) will be approximately A . 3739.662 B. 1500 calorie c. 1500 kilo calorie D. 1500 erg. | 11 |

12 | The graph drawn between presure and volume in boyles law experiment is shown in figure, then: A ( cdot T_{1}>T_{2} ) в. ( T_{2}>T_{1} ) ( c cdot T_{1}=T_{2} ) D. ( frac{T_{1}}{T_{2}}=C ) | 11 |

13 | If at the same temperature and pressure, the densities of two diatomic gases are ( d_{1} ) and ( d_{2} ) respectively, the ratio of mean kinetic energy per molecule of gases will be : A . 1: 1 B . ( d_{1}: d_{2} ) D. ( sqrt{d_{2}}: sqrt{d_{1}} ) | 11 |

14 | A molecule of gas in a container hits one wall (1) normally and rebounds back. It suffers no collision and hits the opposite wall (2) which is at an angle of ( 30^{circ} ) with wall 1 Assuming the collisions to be elastic and the small collision time to be the same for both the walls, the magnitude of average force by wall 2. ( left(F_{2}right) ) provided the molecule during collision satisfy ( mathbf{A} cdot F_{1}>F_{2} ) B. ( F_{1}<F_{2} ) C ( cdot F_{1}=F_{2}, ) both non-zero D. ( F_{1}=F_{2}=0 ) | 11 |

15 | A sample of gas in a box is at pressure ( P_{0} ) and temperature ( T_{0} . ) If number of molecules is doubled and total kinetic energy of the gas kept constant then final temperature and pressure will be ( mathbf{A} cdot T_{0} cdot P_{0} ) в. ( T_{0} .2 P_{0} ) c. ( frac{T_{0}}{2} .2 P_{0} ) D. ( frac{T_{0}}{2} cdot P_{0} ) | 11 |

16 | A cylinder of capacity ( 20 L ) is filled with ( boldsymbol{H}_{2} ) gas. The total average kinetic energy of translatory motion of its molecules is ( 1.5 times 10^{5} J . ) The pressure of hydrogen in the cylinder is A ( .2 times 10^{6} mathrm{N} / mathrm{m}^{2} ) в. ( 3 times 10^{6} mathrm{N} / mathrm{m}^{2} ) c. ( 4 times 10^{6} N / m^{2} ) D. ( 5 times 10^{6} N / m^{2} ) | 11 |

17 | The number of vibrational degrees of freedom for a ( C O_{2} ) molecule is ( A cdot 4 ) B. 5 ( c cdot 6 ) D. | 11 |

18 | The average kinetic energy of thermal neutron is of the order of : (Boltzmann’s constant ( k_{B}=8 times ) ( left.10^{-5} e V / Kright) ) A . ( 0.03 e V ) в. ( 3 e V ) c. ( 3 k e V ) D. 3MeV | 11 |

19 | Three closed vessels ( A, B ) and ( C ) are at the same temperature T and contain gases which obey Maxwell distribution law of velocities. Vessel A contains ( O_{2}, ) B only ( N_{2} ) and ( mathrm{C} ) mixture of equal quantities of ( mathrm{O}_{2} ) and ( N_{2} ). If the average speed of ( O_{2} ) molecules in vessel ( mathrm{A} ) is ( V_{1} ) and that of ( N_{1} ) molecules in vessel B is ( V_{2} ), then the average speed of the ( O_{2} ) molecules in vessel C is A ( cdot frac{left(v_{1}+v_{2}right)}{2} ) B. ( V_{1} ) c. ( sqrt{v_{1} v_{2}} ) D. None of these | 11 |

20 | A light container having a diatomic gas enclosed with in is moving with velocity v. Mass of the gas is ( M ) and number of moles is ( n ) What is the kinetic energy of gas with respect to centre of mass of the system? What is the kinetic energy of gas with respect to ground? | 11 |

21 | When an air bubble of radius r rises from the bottom to the surface of a lake, its radius becomes ( 5 r / 4( ) the pressure of the atmosphere is equal to the ( 10 mathrm{m} ) height of water column).ff the temperature is constant and the surface tension is neglected, the depth of the lake is A . 3.53m B. 6.53m c. ( 9.53 mathrm{m} ) D. 12.53m | 11 |

22 | In physics, the mean free path is the average distance traveled by a moving particle (such as an atom, a molecule, a photon) between successive impacts (collisions), which modify its direction or energy or other particle properties. In which of the following mean free path is used ? A. to estimate the resistivity of a material B. to design a chemical apparatus c. It can be used in optics and in acoustics D. All of the above | 11 |

23 | An inverted vessel (bell) lying at the bottom of a lake, ( 50.6 mathrm{m} ) deep has ( 50 mathrm{cc} ) of air trapped in it. The bell is brought to the surface of lake. The volume of the trapped air will now be A . 200 ç B. 250 cc c. 300 cc D. 350 cc | 11 |

24 | STATEMENT-1: According to kinetic theory of gases the internal energy of a given sample of an ideal gas is only kinetic. STATEMENT-2: The ideal gas molecules exert force on each other only when they collide. A. STATEMENT-1 is True, STATEMENT-2 is True; STATEMENT-2 is a 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 |

25 | Consider a classroom of dimensions ( (5 times 10 times 3) m^{3} ) at temperature ( 20^{circ} C ) and pressure 1 atm. There are 50 people in the room, each losing energy at the average of 150 watts. Assuming that the walls, ceiling, floor, and furniture are perfectly insulated and none of them is absorbing heat. How much time will be needed for raising the temperature of air in the room to the body temperature ( left(37^{circ} Cright) ?left[text { For air } C_{p}=right. ) ( frac{7}{2} R ) and neglect the loss of air to the outside as the temperature rises A .422 sec в. ( 411.3 mathrm{sec} ) c. ( 421.1 mathrm{sec} ) D. ( 413.1 mathrm{sec} ) | 11 |

26 | An ideal gas is heated in a container that has a fixed volume. Identify which of the following will increase as a result of this heating? I. The pressure against the walls of the container Il. The average kinetic energy of the gas molecules III. The number of moles of gas in the container A. I only B. I and II only c. II and III only D. II only E . III only | 11 |

27 | Assertion The total translational kinetic energy of all the molecules of a given mass of an ideal gas is 1.5 times the product of its pressure and its volume. Reason The molecules of a gas collide with each other and the velocities of the molecules change due to the collision. 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 is correct | 11 |

28 | In rising from the bottom of a lake to the top, the temperature of air bubble remains unchanged, but the diameter gets doubled. If ( h ) is the barometric height (expressed in metres of mercury of relative density ( rho ) ) at surface of the lake, the depth of the lake (in metres) is ( mathbf{A} cdot 8 rho h ) B. ( 4 rho h ) ( c cdot 7 rho h ) D. ( 2 rho h ) | 11 |

29 | If ( bar{v}, v_{r m s} ) and ( v_{p} ) represent the mean speed, root mean square and most probable speed of the molecules in an ideal monoatomic gas at temperature ( T ) and if ( m ) is mass of the molecule, then A ( cdot v_{p}<bar{v}<v_{r m} ) B. No molecule can have a speed greater than ( sqrt{2 v_{r m s}} ) C. No molecule can have a speed less than ( v_{p} / sqrt{2} ) D. None of the above | 11 |

30 | A gas has an average speed of ( 10 m / s ) and an average time of ( 0.1 s ) between collisions.What is its mean free path? A. ( 1 m ) в. ( 0.1 m ) ( c .2 m ) D. None of the above | 11 |

31 | The gases carbon-monoxide ( (C O) ) and nitrogen at the same temperature have kinetic energies ( boldsymbol{E}_{1} ) and ( boldsymbol{E}_{2} ) respectively Then A. ( E_{1}=E_{2} ) в. ( E_{1}>E_{2} ) c. ( E_{1}<E_{2} ) D. ( E_{1} ) and ( E_{2} ) cannot be compared | 11 |

32 | A gas mixture contain ( 1 g H_{2} ) and ( 1 g H_{e} ) temperature of gas mixture is increased from ( 0^{circ} ) to ( 100^{circ} C ) at isobaric process. Then find given heat of gas mixture ( left[gamma_{H e}=mathbf{5} / 3, gamma_{H e}=mathbf{7} / mathbf{5}, R=2 c a l / m o lright. ) A . 124 call в. 327 cal c. 218 cal D. 475 cal | 11 |

33 | Estimate the mean free path and collision frequency of a nitrogen molecule in a cylinder containing nitrogen at 2.0 atm and temperature 17 ( ^{o} C . ) take the radius of a nitrogen molecule to be roughly 1.0 A. Compare the collision time with the time the molecule moves freely between two successive collisions (Molecular mass of ( mathrm{N}_{2}=28.0 mathrm{u} ) | 11 |

34 | The average kinetic energy of hydrogen molecule at NTP will be A. ( 0.4 times 10^{-20} ) Joule /molecule B . ( 1.56 times 10^{-20} ) Joule / molecule c. zero D. ( 5.6 times 10^{-20} ) Joule /molecule | 11 |

35 | The number of gas molecules striking per second per square meter of the top surface of a table placed in a room at ( 20^{circ} mathrm{C} ) and 1 atmospheric pressure is of the order of ( left(k_{B}=1.4 times 10^{-23} J / K, ) and right. the average mass of an air molecule is ( left.mathbf{5} times mathbf{1 0}^{-mathbf{2 7}} mathbf{k g}right) ) ( A cdot 10^{27} ) B. ( 10^{23} ) ( c cdot 10^{25} ) D. ( 10^{2} ) | 11 |

36 | The ( H ) calories of heat is required to increase the temperature of one mole of monoatomic gas from ( 20^{circ} mathrm{C} ) to ( 30^{circ} mathrm{C} ) at constant volume. The quantity of heat required to increase the temperature of 2 moles of a diatomic gas from ( 20^{circ} mathrm{C} ) to ( 25^{circ} C ) is at constant volume is : A ( cdot frac{4 H}{3} ) в. ( frac{5 H}{3} ) c. ( 2 H ) D. ( frac{7 H}{3} ) | 11 |

37 | Identify the type of gas filled in container ( A ) and ( B ) respectively A. Mono, mono B. Dia, dia C. Mono, dia D. Dia, Mono | 11 |

38 | State whether true or false: Mean free path order for some gases at ( 273 mathrm{K} ) and 1 atm ( mathrm{P} ) is ( boldsymbol{H} boldsymbol{e}>boldsymbol{H}_{2}>boldsymbol{O}_{2}>boldsymbol{N}_{2}>boldsymbol{C} boldsymbol{O}_{2} ) A. True B. False | 11 |

39 | At what temperature will the mean molecular energy of a perfect gas be one-third of its value of ( 27^{circ} mathrm{C} ? ) A ( cdot 10^{circ} mathrm{C} ) В . ( 10^{1} mathrm{K} ) ( c cdot 10^{2} k ) D. ( 10^{3} ) J | 11 |

40 | A 100 feet long classroom maintains seating row after every 10 feet and has doors on both front and back sides. A laughing gas ( left(N_{2} Oright) ) cylinder and a tear gas (methane) cylinder were opened simultaneously at the front and the back door respectively. Assuming both the gases were present at the same temperature and pressure and the cylinder has similar valve dimensions. If the student of ( n^{t h} ) row, from the front, simultaneously weeps and laughs, the value of ( n ) is A. 5 B. 4 ( c cdot 6 ) D. | 11 |

41 | A certain mass of an ideal gas undergoes a reversible isothermal compression. Its molecules, compared with the initial state, will then have the same (i) root mean square velocity (ii) mean momentum (iii) mean kinetic energy ( A cdot(i),(text { ii) },( text { iii) } ) B. (i), (ii) c. (ii), (iii) D. (i) | 11 |

42 | Absolute zero (OK) is that temperature at which A. Matter ceases to exit B. Ice melts and water freezes c. volume and pressure of a gas become zero D. None of the above | 11 |

43 | Two gases, carbon monoxide ( (C O) ) and nitrogen ( left(N_{2}right) ) at the same temperature have kinetic energies ( boldsymbol{E}_{1} ) and ( boldsymbol{E}_{2} ) respectively. Then A ( . E_{1}=E_{2} ) в. ( E_{1}>E_{2} ) ( mathbf{c} cdot E_{1}<E_{2} ) D. ( E_{1} ) and ( E_{2} ) cannot be compared | 11 |

44 | A cylinder contains helium at 2.5 atmosphere pressure. Another identical cylinder contains argon at 1.5 atmosphere pressure at the same temperature. If both the gases are filled in any one of the cylinders, the pressure of the mixture will be: A. 1.5 atm B. 2.5 atm ( c cdot 4 a t m ) D. none of these | 11 |

45 | Calculate the average molecular kinetic energy : (a) per kilomole, (b) per kilogram, of oxygen at ( 27^{circ} mathrm{C} ) ( (R=8320 J / K m o l e K, ) Avogadro’s number ( =mathbf{6 . 0 3} times ) ( 10^{26} ) molecules ( / ) Kmole | 11 |

46 | One ( k g ) of a diatomic gas is at a pressure of ( 8 times 10^{4} mathrm{N} / mathrm{m}^{2} . ) The density of the ( operatorname{gas} ) is ( 4 mathrm{kg} / mathrm{m}^{3} . ) What is the energy of the gas due to its thermal motion? A. ( 3 times 10^{4} mathrm{J} ) B . ( 5 times 10^{4} mathrm{J} ) c ( cdot 6 times 10^{4} mathrm{J} ) D. ( 7 times 10^{4} mathrm{J} ) | 11 |

47 | Assertion Mean free path of a gas molecules varies inversely as density of the gas. Reason Mean free path varies inversely as pressure of the gas. A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion c. Assertion is correct but Reason is incorrect D. Both Assertion and Reason are incorrect | 11 |

48 | The mean free path of a gas varies with absolute temperature as: A. ( T ) B. ( T^{-1} ) ( c cdot T^{2} ) ( mathbf{D} cdot mathbf{T}^{4} ) | 11 |

49 | The quantity of heat required to heat 1 mole of a monoatomic gas through one degree ( K ) at constant pressure is: A . 3.5 B. 2.5 R ( c cdot 1.5 R ) D. none of these | 11 |

50 | Two kg of a monoatomic gas is at a pressure of ( 4 times 10^{4} N / m^{2} . ) The density of the gas is ( 8 k g / m^{3} . ) What is the order of energy of the gas due to its thermal motion? A ( cdot 10^{3} J ) ( J ) В. ( 10^{5} J ) ( c cdot 10^{6} J ) D. ( 10^{4} J ) | 11 |

51 | A monoatomic ideal gas undergoes a process in which the ratio of ( boldsymbol{P} ) to ( boldsymbol{V} ) at any instant is constant and equal to unity. The molar heat capacity of gas is: ( mathbf{A} cdot 1.5 R ) B. ( 2.0 R ) c. ( 2.5 R ) D. 0 | 11 |

52 | Match following | 11 |

53 | Three containers of the same volume contain three gases. The masses of their molecules being ( mathrm{m}_{1}, mathrm{m}_{2} ) and ( mathrm{m}_{3} ) and number of molecules in these containers is ( mathrm{N}_{1}, mathrm{N}_{2} ) and ( mathrm{N}_{3} ). The pressure in the containers are ( mathrm{P}_{1}, mathrm{P}_{2} ) and ( mathrm{P}_{3} ) respectively. All the gases are now mixed up and put in these containers. The pressure ( mathrm{P} ) of the mixture is ( mathbf{A} cdot Pleft(P_{1}+P_{2}+P_{3}right) ) | 11 |

54 | 2kg of lce block should be dropped from “x km’ height to melt completely. The 8 kg of ice block should be dropped from height ( A cdot 4 x k m ) B. ( times mathrm{km} ) c. ( 2 times mathrm{km} ) D. 3x | 11 |

55 | The number of molecules in ( 22.4 mathrm{cm}^{3} ) of nitrogen gas at STP is A ( .6 .023 times 10^{20} ) В. ( 6.023 times 10^{23} ) c. ( 22.4 times 10^{20} ) D. ( 22.4 times 10^{23} ) | 11 |

56 | If the mean free-path of gaseous molecule is ( 60 mathrm{cm} ) at a pressure of ( 1 times ) ( 10^{-4} mathrm{mm} ) mercury, what will be its mean free-path when the pressure is increased to ( 1 times 10^{-2} mathrm{mm} ) mercury? A ( cdot 6.0 times 10^{-1} mathrm{cm} ) B. ( 6.0 mathrm{cm} ) ( mathbf{c} cdot 6.0 times 10^{-2} mathrm{cm} ) D. ( 6.0 times 10^{3} mathrm{cm} ) | 11 |

57 | A vessel containing 9 litres of an ideal gas at ( 760 mathrm{mm} ) pressure is connected to an evacuated 9 litre vessel. The resultant pressure is ( A cdot 380 mathrm{mm} ) B. 760 mm c. ( 190 mathrm{mm} ) D. 1140 mm | 11 |

58 | An insulated box containing monatomic ideal gas of molar mass ( mathrm{M} ) is moving with a uniform speed v. The box suddenly stops and consequently the gas acquires a new temperature. Calculate the change in the temperature of the gas. Neglect heat absorbed by the box. A ( cdot Delta T=2 frac{M v^{2}}{3 R} ) в. ( Delta T=frac{M v^{2}}{3 R} ) ( ^{mathbf{C}} Delta T=3 frac{M v^{2}}{3 R} ) D. ( quad Delta T=4 frac{M v^{2}}{3 R} ) | 11 |

59 | The maximum speed of the molecules of a gas in a vessel is ( 400 mathrm{m} / mathrm{s} ). If half of the gas leaks out, at constant temperature, the ( r m s ) speed of the remaining molecules will be- A. ( 800 mathrm{m} / mathrm{s} ) B . ( 400 sqrt{2} mathrm{m} / mathrm{s} ) c. ( 400 mathrm{m} / mathrm{s} ) D. ( 200 mathrm{m} / mathrm{s} ) | 11 |

60 | A certain mass of hydrogen gas is introduced into a vessel at room temperature, the final pressure of the gas in the vessel is ( A cdot 85 mathrm{cm} ) of ( mathrm{Hg} ) B. 78 cm of Hg ( c cdot 63 mathrm{cm} ) of ( mathrm{Hg} ) D. ( 58 mathrm{cm} ) of ( mathrm{Hg} ) | 11 |

61 | Two blocks of the same metal having the same mass and at temperature ( T_{1} ) and ( T_{2}, ) respectively. are brought in contact with each other and allowed to attain thermal equilibrium at constant pressure. The change in entropy, ( Delta S ), for this process is : ( ^{mathbf{A}} cdot 2 C_{p} ln left(frac{T_{1}+T_{2}}{4 T_{1} T_{2}}right) ) ( ^{mathrm{B}} 2 C_{p} ln left[frac{left(T_{1}+T_{2}right)^{frac{1}{2}}}{T_{1} T_{2}}right] ) ( ^{mathbf{c}} cdot_{C_{p} l n}left[frac{left(T_{1}+T_{2}right)^{2}}{4 T_{1} T_{2}}right] ) D ( cdot 2 C_{p} ln left[frac{T_{1}+T_{2}}{2 T_{1} T_{2}}right] ) | 11 |

62 | Density is least in A. Sold B. Liquid c. Both A and B D. Gas | 11 |

63 | Modern vacuum pumps can evacuate a vessel down to a pressure of ( 4.0 times ) ( 10^{-15} ) atm. At room temperature ( (300 K), ) taking ( R= ) ( mathbf{8 . 3 J K}^{-1} quad boldsymbol{m o l e}^{-1}, mathbf{1} quad boldsymbol{a t m}= ) ( mathbf{1 0}^{5} boldsymbol{P a} quad ) and ( boldsymbol{N}_{text {Avagadro }}=mathbf{6} times ) ( 10^{23} ) mole ( ^{-1} ), the mean distance between the molecules of gas in an evacuated vessel will be of the order of : ( mathbf{A} cdot 0.2 mu m ) B. ( 0.3 mu ) m ( c .0 .2 mathrm{mm} ) D. ( 0.2 n m ) | 11 |

64 | The temperature of a gas is due to A. P.E. of its molecules B. K.E. of its molecules C. Attractive forces between molecules D. Repulsive forces between molecules | 11 |

65 | ( Delta C_{p} ) for change ( N_{2}(g)+3 H_{2}(g)= ) ( mathbf{2} N boldsymbol{H}_{3}(boldsymbol{g}) ) is: ( mathbf{A} cdot C_{p N H_{3}}-left(C_{p N_{2}}right) ) B . ( 2 C_{p N H_{3}}-left(C_{p N_{2}}+3 C_{p H_{2}}right) ) ( mathbf{c} cdot 2 C_{p N H_{3}}-left(C_{p H_{2}}right) ) D ( cdot 2 C_{p N H_{3}}+left(C_{p N_{2}}+3 C_{p H_{2}}right) ) | 11 |

66 | A volume of ( 2.5 ~ L ) of a sample of a gas at ( 27^{circ} mathrm{C} ) and 1 bar pressure is compressed to a volume of 500 ml keeping the temperature constant, the percentage increase in pressure is? ( mathbf{A} cdot 100 % ) B. ( 400 % ) c. ( 500 % ) D. ( 80 % ) | 11 |

67 | The average thermal energy of a oxygen atom at room temperature ( left(27^{circ} Cright) ) A ( cdot 4.5 times 10^{-21} J ) В. ( 6.2 times 10^{-21} J ) c. ( 3.4 times 10^{-21} J ) D. ( 1.8 times 10^{-21} mathrm{J} ) | 11 |

68 | When an ideal diatomic gas is heated at constant pressure, the fraction of the heat energy supplied which increases the internal energy of the gas is? A. ( 2 / 5 ) B. 3/5 c. ( 3 / 7 ) D. ( 5 / 7 ) | 11 |

69 | The law of equipartition of energy is applicable to the system whose constituents are : A. in random motion B. in orderly motion c. at rest D. moving with constant speedd | 11 |

70 | The average kinetic energy of a molecule of a perfect gas is : A ( cdot frac{2}{3} k T ) B. ( 1.5 k T ) c. ( 2.5 k T ) D. none of these | 11 |

71 | If a gas mixture contains 2 moles of ( boldsymbol{O}_{2} ) and 4 moles of Ar at temperature ( T ) then what will be the total energy of the system (neglecting all vibrational modes) A . 11 RT B. 15 RT c. 8 RT D. RT | 11 |

72 | An ideal gas having initial pressure ( P ) volume ( V ) and temperature ( T ) is allowed to expand adiabatically until its volume becomes ( 5.66 mathrm{V} ) while its temperature falls to ( T / 2 . ) How many degrees of freedom do the gas molecules have? A. 7 B. 5 ( c cdot 6 ) D. | 11 |

73 | One mole of a monoatomic gas is mixed with 3 mole of a diatomic gas. The molar heat capacity at constant volume of mixture (in cal) is : A . 4.5 B. 2 ( c cdot 4 ) D. | 11 |

74 | In Rutherford alpha particles scattering experiment, thin layer of which metal was used? A. Aluminium B. Gold c. silver D. zinç | 11 |

75 | One half mole each of nitrogen, oxygen and carbon dioxide are mixed in enclosure of volume 5 litres and temperature ( 27^{circ} mathrm{C} . ) The pressure exerted by mixture is ( left(boldsymbol{R}=mathbf{8 . 3 1} boldsymbol{J} boldsymbol{m o l}^{-1} boldsymbol{K}^{-1}right) ) A ( cdot 7.48 times 10^{5} mathrm{N} mathrm{m}^{-2} ) B. ( 4 times 10^{5} mathrm{N} mathrm{m}^{-2} ) ( mathbf{c} cdot 6 times 10^{5} mathrm{N} m^{-2} ) D. ( 3 times 10^{5} mathrm{N} m^{-2} ) | 11 |

76 | Volume of oxygen at NTP, required to completely burn 1 kg of coal (100% arbon) is A . 22.4 ( L ) В. ( 1.86 times 10^{3} mathrm{L} ) c. ( 22.4 times 10^{3} mathrm{L} ) D. 1000 L | 11 |

77 | Calculate the means free path of nitrogen molecule at ( 27^{circ} mathrm{C} ) when pressure is 1.0 atm. Given, diameter of nitrogen molecule ( =1.5 stackrel{o}{A}, k_{B}= ) ( 1.38 times 10^{-23} J K^{-1} . ) If the average speed of nitrogen molecule is ( 675 m s^{-1} ). The time taken by the molecule between two successive collisions is? A. 0.6 ns B. ( 0.4 mathrm{ns} ) c. ( 0.8 mathrm{ns} ) D. 0.3 ns | 11 |

78 | The gas mixture constists of 3 moles of oxygen and 5 moles of argon at temperature ( T . ) Considering only translational and rotational modes, the total internal energy of the system is: A . ( 12 R T ) в. ( 20 R T ) c. ( 15 R T ) D. ( 4 R T ) | 11 |

79 | A gas has a molecular diameter of ( 0.1 mathrm{m} ) It also has a mean free path of ( 2.25 mathrm{m} ) What is its density? A ( cdot 10^{-3} ) B . ( 10^{-2} ) ( mathbf{c} cdot 10^{-4} ) D. ( 10^{-5} ) | 11 |

80 | The value of rotational K.E. at temperature T of one gram molecules of a diatomic gas will be- | 11 |

81 | A vessel of volume ( V ) contains ( n_{1} ) moles of oxygen and ( n_{2} ) moles of carbon dioxide at absolute temperature T. The pressure of the mixture is A. ( frac{left(n_{1}+n_{2}right) R T}{V} ) В. ( frac{left(n_{1}-n_{2}right) R T}{V} ) c. ( frac{n_{1} n_{2} R T}{V} ) D. ( frac{n_{1} R T}{n_{2} V} ) | 11 |

82 | Choose the only correct statement from the following A. The pressure of a gas is equal to the total kinetic energy of the molecules in a unit volume of the gas. B. The product of pressure and volume of a gas is always constant. C. The average kinetic energy of molecules of a gas is proportional to its absolute temperature. D. The average kinetic energy of molecules of a gas is proportional to the square root of its absolute temperature. | 11 |

83 | ( p-frac{1}{v} ) graph for a gas under constant temperature is A. Straight line B. Circle c. hyperbola D. parabola | 11 |

84 | The average velocity of the molecules in a gas in equilibrium is A. proportional to ( sqrt{T} ) B. proportional to T C. proportional to ( T^{2} ) D. equal to zero | 11 |

85 | Calculate the kinetic energy of 10 gram of Argon molecules at ( 127^{circ} mathrm{C} ) [Universal gas constant ( boldsymbol{R}= ) ( 8320 J / ) mol ( K . ) Atomic weight of Argon ( =mathbf{4 0} k boldsymbol{g} / boldsymbol{m o l}] ) | 11 |

86 | A gas mixture consists of 2 moles of oxygen and 4 moles of Argon at temperature T. Neglecting all vibrational modes, the total internal energy of the system is? A . ( 4 mathrm{RT} ) B. 9 RT ( c .11 R T ) D. 15RT | 11 |

87 | The heat capacity of a diatomic gas is higher than that of a mono-atomic gas.If true enter 1 else 0 | 11 |

88 | According to the Boltzmann’s law of equipartition of energy, the energy per degree of freedom and at a temperature T K is : A. (3/2) KT B. (2/3) KT c. кт D. 1/2 KT | 11 |

89 | ( 28 g ) of ( N_{2} ) gas is contained in a flask at a pressure 10 atm and at a temperature of ( 57^{0} C . ) It is found that due to leakage in the flask, the pressure is reduced to half and the temperature reduced to ( 27^{0} ) C.The quantity of ( N_{2} ) gas that leaked out is: ( mathbf{A} cdot frac{11}{20} mathrm{g} ) B. ( frac{80}{11} ) g c. ( frac{5}{63} ) g D. ( frac{63}{5} g ) | 11 |

90 | The mass of ( mathrm{O}_{2} ) molecule is 16 times that ( mathrm{H}_{2} ) molecule. The rms velocity of ( mathrm{O}_{2} ) molecule at room temperature ( mathrm{C}_{r m s} ). The rms velocity of ( mathrm{H}_{2} ) molecule at the same temperature will be: A ( cdot frac{C_{r m s}}{16} ) в. ( frac{C_{r m s}}{4} ) ( mathbf{c} cdot 4 C_{r m s} ) D. ( 16 C_{r m} ) | 11 |

91 | One mole of an ideal monoatomic gas is mixed with 1 mole of an ideal diatomic gas. The molar specific heat of the mixture at constant volume is : A. 3 cal B. 4 cal ( c cdot 8 ) cal D. 9 cal | 11 |

92 | Assertion ( V_{r m s} ) and ( V_{text {mean }} ) of gaseous molecules is nearly of the order of velocity of sound. Reason The sound travels in air because of vibrational molecular motion. 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 |

93 | Assertion In the formula ( P=frac{2}{3} E, ) the term ( E ) represents translational kinetic energy per unit volume of gas. Reason In case of monoatomic gas translational kinetic energy and total kinetic energy are equal. 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 |

94 | When we cool a gas below its condensation point, the K.E. of its molecules: A . increases B. decreases c. remains the same D. first decreases then increases | 11 |

95 | The ( u_{r m s} ) of gas at ( 327^{circ} C ) is : A ( cdot 611.66 frac{m}{s e c} ) В . ( 19342.44 frac{mathrm{m}}{mathrm{sec}} ) с. ( 1223.22 frac{m}{s e c} ) D. ( 96.71 frac{m}{s e c} ) | 11 |

96 | What is number of degrees of freedom of an ideal diatomic molecule at ordinary temperature? A. 7 B. 6 ( c cdot 5 ) D. | 11 |

97 | Boyle’s law is valid for real gases at : a) low pressure b) high pressure c) low temperature d) high temperature ( A cdot a, c ) в. а, ( c cdot b, c ) D. b, | 11 |

98 | The total kinetic energy of 8 litres of helium molecules at 5 atmosphere pressure will be A. 6078 erg B. 6078 Joule ( c .607 ) erg D. 607 Joule | 11 |

99 | In a thermodynamic system, working substance is ideal gas, its internal energy is in the form of A. Kinetic energy B. Kinetic and potential energy c. Potential energy D. None of the above | 11 |

100 | A sample of an ideal gas is contained in a cylinder. The volume of the gas is suddenly decreased. A student makes the following statements to explain the change in pressure of the gas. I. The average kinetic energy of the gas atoms increases. II. The atoms of the gas hit the walls of the cylinder more frequently. III. Temperature of the gas remains unchanged. Which of these statements is true? A. I and II only B. I and III only c. ॥ and III only D. I, II and III | 11 |

101 | A system consists of ( mathrm{N} ) particles, which have independent K relations among one another. The number of degrees of freedom of the system is given by : ( A cdot 3 N K ) B. N/3K ( c .3 mathrm{N} / mathrm{K} ) D. 3N – K | 11 |

102 | Maxwell’s laws of distribution of velocities shows that A. the number of molecules with most probable velocity is very large B. the number of molecules with most probable velocity is small C. the number of molecules with most probable velocity is zero D. the number of molecules with most probable velocity is exactly equal to 1 | 11 |

103 | ( 24 mathrm{J} ) of heat are added to a gas in a container, and then the gas does 6 J of work on the walls of the container. What is the change in internal energy for the gas? A . – 30 B . – 18 J c. 4 J D. 18 J E. 30 | 11 |

104 | 000 voe | 11 |

105 | At constant pressure, the ratio of increase in volume for an ideal gas per degree rise in kelvin temperature to its original volume is : ( A ) в. ( frac{1}{alpha} ) c. ( frac{1}{sqrt{alpha}} ) ( D cdot sqrt{alpha} ) | 11 |

106 | Kinetic energy of a gas molecule depends on: A. Volume B. Temperature c. Pressure D. None of these | 11 |

107 | What is the average translational kinetic energy of a molecule of an ideal gas at temperature of ( 27^{circ} mathrm{C} ) | 11 |

108 | Energy of all molecules of a monatomic gas having a volume ( V ) and pressure ( P ) is ( frac{3}{2} boldsymbol{P} boldsymbol{V} ). The total translational kinetic energy of all molecules of a diatomic gas at the same volume and pressure is A ( cdot frac{1}{2} P V ) в. ( frac{3}{2} P V ) c. ( frac{5}{2} P V ) D. 3PV | 11 |

109 | 3 mole of ( A g ) is heated from ( 300 K ) to 1000 ( K ). Calculate ( Delta H ) when ( P=1 ) at ( m ) and ( C_{p}=23+0.01 T ) A. ( 62 k J / m o l ) B. ( 45 mathrm{kJ} / mathrm{mol} ) c. ( 38 k J / m o l ) D. ( 54 ~ k J / m o l ) | 11 |

110 | Choose the wrong options This question has multiple correct options A. Translation kinetic energy of all ideal gases at same temperature is same B. In one degree of freedom all ideal gases has internal energy ( =frac{1}{2} R T ) C. Translational degree of freedom of all ideal gases is three D. Translational kinetic energy of one mole of all ideal gases is ( frac{3}{2} R T ) | 11 |

111 | The initial internal energy of the gas in container ‘A’, if the containers were at room temperature ( 300 mathrm{K} ) initially- A . 1406.25 cal в. 1000 cal c. 2812.5 cal D. none of these | 11 |

112 | The kinetic energy of 1 gram mole of a gas at normal temperature and pressure is ( (mathrm{R}=8.31 mathrm{J} / mathrm{mole}-mathrm{K}) ) A ( cdot 0.56 times 10^{4} J ) В. ( 1.3 times 10^{2} J ) c. ( 2.7 times 10^{2} J ) D. 3.4 ( times 10^{3} mathrm{J} ) | 11 |

113 | The specific heat of an ideal gas depends on temperature is- A ( cdot frac{1}{T} ) в. ( T ) c. ( sqrt{T} ) D. Does not depend on temperature | 11 |

114 | If the pressure of a gas is increased then its mean free path becomes: A . zero B. less c. more ( D cdot alpha ) | 11 |

115 | A container is divided into two equal parts I and II by a partition with a small hole of diameter d. The two partitions are filled with same ideal gas, but held at temperatures ( boldsymbol{T}_{boldsymbol{I}}=mathbf{1 5 0 K} ) and ( boldsymbol{T}_{boldsymbol{I I}}= ) ( 300 K ) by connecting to heat reservoirs. Let ( lambda_{I} ) and ( lambda_{I I} ) be the mean free paths of the gas particles in the two parts such that ( boldsymbol{d}>>boldsymbol{lambda}_{boldsymbol{I}} ) and ( boldsymbol{d}>>boldsymbol{lambda}_{boldsymbol{I} I} . ) Then ( boldsymbol{lambda}_{I} / boldsymbol{lambda}_{I I} ) is close to. ( mathbf{A} cdot 0.25 ) B. 0.5 c. 0.7 D. 1.0 | 11 |

116 | If the pressure in a closed vessel is reduced by drawing out some gas, the mean-free path of molecules: A. is decreased B. is increased c. remains unchanged D. increases or decreases according to the nature of the gas | 11 |

117 | The mean free path and rms velocity of a nitrogen molecule at a temperature ( 17 mathrm{C} ) are ( 1.2 times 10^{-7} mathrm{m} ) and ( 5 times 10^{2} mathrm{m} / mathrm{s} ) respectively.The time between two successive collisions A . ( 2.4 times 10^{-10} mathrm{s} ) B . ( 1.2 times 10^{-10} mathrm{s} ) c. ( 3.4 times 10^{-13} ) s D. 3.4 ( times 10^{-10} ) s | 11 |

118 | At what temperature will the linear kinetic energy of a gas molecule be equal to that of an electron accelerated through a potential difference of ( 10 mathrm{V} ? ) ( A cdot ) 273 ( k ) В . ( 19 times 10^{3} K ) c. ( 38.65 times 10^{3} ) D. ( 11.3 times 10^{3} K ) | 11 |

119 | The graph drawn between pressure and volume in Boyle’s law experiment is shown in figure for different masses of same gas at same temperature then ( mathbf{A} cdot m_{2}>m_{1} ) В ( cdot m_{1}>m_{2} ) ( mathbf{c} cdot m_{1}=m_{2} ) ( mathbf{D} cdot m_{1}^{3}>m_{2} ) | 11 |

120 | A vessel contains a gas under a pressure of ( 5 times 10^{5} ) pa. If ( frac{3}{5} ) of the mass of the gas is flown out,What will be the gas pressure if the temperature being maintained constant. A. 50 MPa B. 2MPa c. о.२мРа D. 0.5MPa | 11 |

121 | The average translational kinetic energy of air molecules is ( 0.040 e V ) ( mathbf{1} e V=mathbf{1 . 6} times mathbf{1 0}^{-19} mathbf{J} ) ). Calculate the temperature of the air. Boltzman’s constant ( k=1.38 times 10^{-23} J K^{-1} ) | 11 |

122 | A closed vessel contains a mixture of two gases Neon & Argon the total mass of mixture is 28 gm.The partial pressure due to Argon and neon are 4 atm and 12atm respectively.The mass of individual gases in vessel is ( left(M_{text {neon}}=right. ) ( left.20, M_{text {argon}}=40, R=8.3 mathrm{J} / mathrm{mol}-mathrm{k}right) ) A. ( 4 mathrm{gm}, 24 mathrm{gm} ) B . ( 1 mathrm{gm}, 27 mathrm{gm} ) ( mathrm{c} cdot 6 mathrm{gm}, 22 mathrm{gm} ) D. ( 2 g mathrm{m}, 26 mathrm{gm} ) | 11 |

123 | The pressure of a gas in a ( 100 mathrm{mL} ) container is ( 200 mathrm{kPa} ) and the average translation kinetic energy of each gas particle is ( 6 times 10^{-21} ). Find the number of gas particles in the container. How many moles are there in the container? | 11 |

124 | One mole of an ideal gas ( left(C_{v, m}=frac{5}{2} Rright) ) at ( 300 mathrm{K} ) and 5 atm is expanded adiabatically to a final pressure of 2 atm against a constant pressure of 2 atm. Final temperature of the gas is: ( mathbf{A} cdot 270 mathrm{K} ) B. 273 к c. ( 248.5 mathrm{k} ) D. 200 к | 11 |

125 | Mean free path does not depend on ( A cdot rho ) B. T ( c cdot d ) D. | 11 |

126 | Write the postulates of Dalton’s Atomic theory | 11 |

127 | Two rigid boxes containing different ideal gases are placed on a table. Box ( A ) contains one mole of ( N_{2} ) at temperature ( T_{0}, ) while box ( mathrm{B} ) contains one mole of ( boldsymbol{H}_{2} ) at temperature ( 7 / 3 T_{0} . ) The boxes are then put into thermal contact with each other and heat flows between them until the gases reach a common final temperature [lgnore the heat capacity of boxes]. Then the final temperature of the gases ( T_{f} ) in terms of ( boldsymbol{T}_{0} ) is A ( cdot T_{f}=frac{5}{2} ) To B ( T_{f}=frac{3}{7} T o ) c. ( T_{f}=frac{5}{3} ) To D. ( T_{f}=frac{3}{2} ) To | 11 |

128 | Two balloons are filled, one with pure He gas and the other by air, respectively. If the pressure and temperature of these baloons are same then the number of molecules per unit volume is: A. More in the He filled balloon B. Same in both balloons c. More in air filled balloon D. In the ratio of 1: 4 | 11 |

129 | To find out degree of freedom, the correct expression is : A ( cdot f=frac{2}{gamma-1} ) B. ( f=frac{gamma+1}{2} ) ( ^{mathbf{C}} f=frac{2}{gamma+1} ) D. ( f=frac{1}{gamma+1} ) | 11 |

130 | Calculate ( gammaleft(text { ratio of } C_{p} text { and } C_{v}right) ) for triatomic linear gas at high temperature. Assume that the contribution of the vibrational degree of freedom is ( 75 % ? ) A. 1.222 B. 1.121 c. 1.18 D. 1.33 | 11 |

131 | A bullet travelling at ( 100 mathrm{ms}^{-1} ) suddenly hits a concrete wall. If its K.E. is converted completely into heat, the raise in temperature is ( left(s=100 J k g^{-1} K^{-1}right) ) A. 20k в. 40k ( c . ) 50k D. 60k | 11 |

132 | A gas has an average speed of ( 10 mathrm{m} / mathrm{s} ) and a collision frequency of ( 10 s^{-1} . ) What is its mean free path? A. ( 1 m ) в. ( 2 m ) c. ( 3 m^{text {- }} ) D. ( 4 m ) | 11 |

133 | The value of universal gas constant is ( 8.3 J / )mole( / K, ) the mean kinetic energy of ( 32 g m ) of oxygen at ( -73^{circ} C ) will be ( mathbf{A} cdot 480 J ) в. ( 4980 J ) c. ( 2490 J ) D. ( 100 J ) | 11 |

134 | The average kinetic energy of ( O_{2} ) at a particular temperatures is ( 0.768 mathrm{eV} ) The average kinetic energy of ( N_{2} ) molecules in eV at the same temperature is? A . 0.0015 B. 0.0030 c. 0.048 D. 0.768 | 11 |

135 | A column of ( mathrm{Hg} ) of ( 10 mathrm{cm} ) length is contained in the middle of a narrow horizontal ( 1 mathrm{m} ) long tube which is closed at both ends. Both the halves of the tube contain air at a pressure ( 76 mathrm{cm} ) of Hg. The distance of the column of Hg be displaced if the tube is held vertically is A. 3 cms B. 2 cms c. ( 4 mathrm{cms} ) D. ( 1 mathrm{cm} ) | 11 |

136 | From which height a block of ice must be dropped in order that it melts completely. Assume that all the energy is retained by the ice. ( left(g=10 m s^{-2}, L=80 J g m^{-1} a n d J=4.2right. ) ( mathrm{J} / mathrm{cal} ) A. ( 1000 mathrm{Km} ) B. 100Km c. 33.6кm D. ( 1 mathrm{Km} ) | 11 |

137 | 3 mole of gas “X” and 2 moles of gas “Y” enters from end “P” and “Q” of the cylinder respectively. The cylinder has the area of cross section, shown as under The length of the cylinder is ( 150 mathrm{cm} ). The gas “X” intermixes with gas “Y” at the point. If the molecular weight of the gases ( X ) and ( Y ) is 20 and 80 respectively, then what will be the distance of point ( mathbf{A} ) from Q? A. ( 75 mathrm{cm} ) B. ( 50 mathrm{cm} ) c. 37.5 D. ( 90 mathrm{cm} ) | 11 |

138 | ( C_{p}-C_{v} ) for an ideal gas is | 11 |

139 | Identify the best graph which represents the relationship between the average kinetic energy of the molecules of a gas and its temperature? ( A ) B. ( c ) D. E . | 11 |

140 | A rigid container of negligible heat capacity contains one mole of an ideal gas. The temperature of the gas increase by ( 1^{circ} mathrm{C} ) if ( 3 cdot 0 ) cal of heat is added to it. The gas may be This question has multiple correct options A. helium B. argon c. oxygen D. carbon dioxide | 11 |

141 | N’ molecules each of mass ‘m’, of gas A and ‘2N’ molecules, each of mass ‘2m’, of gas ( mathrm{B} ) are contained in the same vessel. Which is maintained at a temperature T. The mean square of the velocity of molecules of B type is denoted by ( V^{2} ) and the mean square of the ( X ) component of the velocity of ( A ) type is denoted by ( omega^{2}, frac{omega^{2}}{V^{2}}= ) ( A cdot 2 ) B. ( c cdot 1 / 3 ) ( D cdot 2 / 3 ) | 11 |

142 | If the pressure of an ideal gas contained in a closed vessel is increased by ( 0.4 % ) the increases in temperature is ( 1^{circ} mathrm{C} ) The initial temperature of the gas is: ( mathbf{A} cdot 26^{circ} C ) B . ( 250^{circ} mathrm{C} ) c. ( 250 K ) D. ( 2500^{circ} mathrm{C} ) | 11 |

143 | An enclosure of volume 3 litre contains 16 ( mathrm{gms} ) of oxygen, ( 7 mathrm{gms} ) of nitrogen and 11 gms of carbon di-oxide at ( 27^{circ} mathrm{C} ). The pressure exerted by the mixture is approximately A. 1 atmosphere B. 3 atmosphere c. 9 atmosphere D. 8.3 atmosphere | 11 |

144 | In Boyles experiment for a given gas at different temperatures the graph drawn between pressure and density are straight lines as shown then: A ( cdot T_{1}>T_{2} ) в. ( T_{2}>T_{1} ) ( mathrm{c} cdot T_{1}=T_{2} ) D. ( T_{1}^{3}=T_{2} ) | 11 |

145 | Consider the following statements for air molecules in an air tight container. (I) The average speed of molecules is larger than root mean square speed. (II) Mean free path of molecules is larger than the mean distance between molecules. (III) Mean free path of molecules increases with temperature (IV) The rms speed of nitrogen molecule is smaller than oxygen molecule. The true statements are. A. Only II B. ॥ & ॥ I c. ॥ & । D. I, II & IV | 11 |

146 | Assertion If a gas container is placed in a moving train, the temperature of gas will increase. Reason Kinetic energy of gas molecules will increase. 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 |

147 | A closed vessel contains some gas at atmospheric pressure and room temperature. It is then given a high speed by placing it in a fast moving train. The temperature of the gas A. will increase B. will decrease c. will remain uncharged D. increase or decrease depending on the chemical composition of gas | 11 |

148 | A man is climbing up a spiral type staircase. His degrees of freedom are : ( mathbf{A} cdot mathbf{1} ) B. 2 ( c cdot 3 ) D. more than 3 | 11 |

149 | The average speed of all the molecules in a gas at a given instant is zero, whereas the average velocity of all the molecules is zero. Explain why? | 11 |

150 | For any distribution of speeds ( V_{r m s} geq ) ( V_{a v} . ) Is this statement true or false? | 11 |

151 | The expression for mean free path is : A ( cdot lambda=frac{K T}{sqrt{2} pi d^{2} P} ) B. ( lambda=frac{pi d P}{k T} ) c. ( _{lambda}=frac{pi d^{2} P}{k T} ) D. ( lambda=frac{k T}{pi d P} ) | 11 |

152 | The total kinetic energy of 1 mole of ( N_{2} ) at ( 27^{circ} C ) will be approximately: A . ( 1500 J ) B. 1500 calorie c. 1500 kilo calorie D. 1500 erg | 11 |

153 | A spherical balloon rises up and the radius become twice that on the ground. Assuming temperature to be constant the pressure at that altitude is A. ( 1 / 3 ) rd of that on the earth B. ( 1 / ) 9th that on the earth’s surface C. ( 1 / 8 ) times of that on the earth’s surface D. 3 times of that on the surface of the earth | 11 |

154 | An air bubble rises from the bottom to the surface of lake and it is found that its diameter is doubled. If the height of water barometer is ( 11 mathrm{m} ), the depth of the lake in meters is A. ( 70 mathrm{m} ) B. 77m ( c .7 .7 mathrm{m} ) D. 78m | 11 |

155 | For which of the following ideal gas ( C_{V, m} ) is independent of temperature? A. ( H e ) в. ( H_{2} ) c. ( C O ) ( mathrm{D} cdot mathrm{SO}_{2} ) | 11 |

156 | Water is falling from 160m height. Assuming that half the K.E. of falling water gets converted into heat, the rise in temperature of water is approximately ( mathbf{A} cdot 0.1^{0} C ) B. ( 0.2^{0} C ) ( mathbf{c} cdot 0.3^{0} C ) D. ( 0.4^{circ} mathrm{C} ) | 11 |

157 | From what minimum height, a block of ice has to be dropped in order that it may melt completely on hitting the ground: ( A cdot m g h ) в. ( frac{m g h}{l} ) c. ( frac{l}{g} ) D. ( frac{h}{l g} ) | 11 |

158 | Variation of ( Delta boldsymbol{H} ) vs temperature is given by: A. Kirchhoff’s equation B. Gibbs-Helmholtz equation c. Clausius-Clapeyron equation D. Van’t Hoff’s equation | 11 |

159 | Which of the following is an assumption of Kinetic theory of matter? A. Molecules are in a state of continuous motion and possess kinetic energy B. The kinetic energy of molecules increases with increase in temperature. c. The molecules of matter always attract each other due to forces of cohesion and adhesion D. All of the above | 11 |

160 | The heat capacity of a certain amount of a particular gas at constant pressure is greater than that at constant volume by ( 29.1 mathrm{J} / mathrm{K} . ) Match the items given in Column I with the items given in Column II. List 1 If the gas is monatomic, heat capacity at constant volume If the gas monatomic, heat capacity at constant pressure | 11 |

161 | Two metal balls of same material having masses ( 50 mathrm{gm} ) and ( 100 mathrm{gm} ) collides with a target with same velocity. Then the ratio of their rise in temperature is A . 1: 2 B. 4: c. 2: D. 1: | 11 |

162 | The ratio of average translational kinetic energy to rotational kinetic energy of a diatomic molecule at temperature ( mathrm{T} ) is ( mathrm{x} / mathrm{y} ) then value of ( x+y ) is | 11 |

163 | A gas in a ( 1 mathrm{m}^{3} ) container has a molecular diameter of ( 0.1 mathrm{m} . ) There are 10 molecules. What is its mean free path? A . ( 2.25 mathrm{m} ) B. 2m ( c .3 m ) ( D cdot 1 m ) | 11 |

164 | A vessel of volume 4 litres contains a mixture of 8 gms of ( mathrm{O}_{2}, 14 ) gms of ( mathrm{N}_{2} ) and 22 gms of ( mathrm{CO}_{2} ) at ( 27^{0} mathrm{C} ). The pressure exerted by the mixture is A. 10 atmosphere B. ( 5 times 10^{6} mathrm{N} / mathrm{m}^{2} ) C ( .7 .79 times 10^{5} mathrm{N} / mathrm{m}^{2} ) D. ( 6 times 10^{5} 5 mathrm{N} / mathrm{m}^{2} ) | 11 |

165 | Energy of all molecules of a monatomic gas having a volume ( V ) and pressure ( P ) is ( frac{3}{2} P V . ) The total translational kinetic energy of all molecules of a diatomic gas at the same volume and pressure is A ( cdot frac{1}{2} P V ) в. ( frac{3}{2} P V ) c. ( frac{5}{2} P V ) D. 3 PV | 11 |

166 | If an air bubble rises from the bottom of the lake to its surface at constant temparature, its volume A . decreases B. increases c. remain same D. can’t say | 11 |

167 | In a thermodynamic process, helium gas obeys the law, ( boldsymbol{T} boldsymbol{P}^{-2 / 5}= ) constant. The heat is given to ( n ) moles of ( H e ) in order to raise the temperature from ( boldsymbol{T} ) to ( mathbf{2} T ) is : ( A cdot 8 R T ) в. ( 4 R T ) c. ( 16 R T ) D. Zero | 11 |

168 | The average kinetic energy of the particles of a gas is most closely associated with which of the following quantity? A. heat capacity. B. temperature c. specific heat D. absolute zero. E. potential enemy. | 11 |

169 | What is the name of ( h & ) what is the value? | 11 |

170 | Ten small planes are flying at a speed of ( 150 mathrm{km} h^{-1} ) in total darkness in an air space that is ( 20 times 20 times 1.5 k m^{3} ) in volume. You are in one of the planes, flying at random within this space with no way of knowing where the other planes are. On the average about how long a time will elapse between near collision with your plane. Assume for this rough computation that a safety region around the plane can be approximated by a sphere of radius 10 ( mathrm{m} ) A. 125 h в. 220h c. 432 h D. 225h | 11 |

171 | A vertical hollow cylinder of height ( 1.52 mathrm{m} ) is fitted with a movable piston of negligible mass and thickness. The lower half portion of the cylinder contains an ideal gas and the upper half is filled with mercury. The cylinder is initially at ( 300 mathrm{K} ) When the temperature is raised half of the mercury comes out of the cylinder. Then the temperature is (the thermal expansion of mercury to be negligible) ( A cdot 437 mathrm{K} ) B. 337.5 K c. ( 275 mathrm{k} ) D. 137.K | 11 |

172 | Explain the inter-conversion of the three states of matter in terms of force attraction and K.E of the molecules. | 11 |

173 | At what temperature the rms velocity of helium molecules will be equal to that of hydrogen molecules at NTP? A . ( 844 k ) B. 64 K c. ( 273^{0} mathrm{C} ) D. 273k | 11 |

174 | The heat capacity of liquid water is ( mathbf{7 5 . 6 J} / boldsymbol{K}-boldsymbol{m o l}, ) while the enthalpy of fusion of ice is ( 6.0 k J / ) mol. What is the smallest number of ice cubes at ( 0^{circ} C ) each containing ( 9.0 g ) of water, needed to cool ( 500 g ) of liquid water from ( 20^{circ} mathrm{C} ) to ( 0^{circ} C ? ) A . 1 B. 7 c. 14 D. 21 | 11 |

175 | When the temperature is increased from ( 0^{circ} mathrm{C} ) to ( 273^{circ} mathrm{C}, ) in what ratio the average kinetic energy of molecules changes? A. B. 5 ( c cdot 4 ) ( D cdot 2 ) | 11 |

176 | The mass of hydrogen molecule us ( 3.32 x ) ( 10^{-27} ) kg.If ( 10^{23} ) hydrogen molecules strike per second at ( 2 mathrm{cm}^{2} ) area of a rigid wall at an angle ( 45^{0} ) from the normal and rebound back with speed of ( 1000 mathrm{m} / mathrm{s} ) then the pressure exerted on the wall is A. 2 Pascal B. 2.34 times 10 ( ^{3} ) Pascal c. ( 0.23 times 10^{3} ) Pascal D. 23.4 x 10 ( ^{3} ) Pascal | 11 |

177 | If the kinetic energy of the molecules in 5 litres of helium at 2 at ( m ) is ( E ). What is the kinetic energy of molecules in 15 litres of oxygen at 3 at ( m ) in terms of ( E ? ) A . ( 7.5 E ) в. ( 7 E ) ( c .8 .5 E ) D. ( 8 E ) | 11 |

178 | The poisson’s ratio for ( O_{2} ) is ( 1.4 . ) Which of the following are correct for ( O_{2} ? ) This question has multiple correct options A. ( C_{V M}=5 c a l ) В. ( C_{V}=0.156 mathrm{cal} ) ( mathbf{c} cdot C_{P}=frac{R Upsilon}{Upsilon-1} ) D. ( C_{V}=frac{R}{(Upsilon-1)} ) | 11 |

179 | A gas mixture consists of 2 moles of oxygen and 4 moles of Argon at temperature T. Neglecting all vibrational moles, the total internal energy of the system is A . ( 4 mathrm{RT} ) в. 15RT c. 9 RT D. 11RT | 11 |

180 | If the total number of ( boldsymbol{H}_{2} ) molecules is double of the ( O_{2} ) molecules then the ratio of total kinetic energies pf ( boldsymbol{H}_{2} ) to that of ( O_{2} ) at ( 300 mathrm{K} ) is : A .1: 1 B. 1: 2 ( c cdot 2: ) ( D cdot 1: 3 ) | 11 |

181 | The amount of heat energy required to raise the temperature of ( 1 g ) of helium in a container of volume ( 10 L, ) from ( T_{1} K ) to ( T_{2} K ) is ( left(N_{a}= ) Avogadros number, right. ( k_{B}= ) Boltzmann constant A ( cdot frac{3}{2} N_{a} k_{B}left(T_{2}-T_{1}right) ) в. ( frac{3}{7} N_{a} k_{B}left(T_{2}-T_{1}right) ) c. ( frac{3}{4} N_{a} k_{B}left(T_{2}-T_{1}right) ) D ( cdot frac{3}{8} N_{a} k_{B}left(T_{2}-T_{1}right) ) | 11 |

182 | A flask contains argon and chlorine in the ratio of 2: 1 by mass. The temperature of the mixture is ( 27^{0} C . ) The ratio of average kinetic energies of two gases per molecule is A . 1: 1 в. 2: 1 ( c .3: 1 ) D. 6: 1 | 11 |

183 | The internal energy of a gas: ( A . ) is the sum total of kinetic and potential energies. B. is the total transitional kinetic energies C . is the total kinetic energy of randomly moving molecules. D. is the total kinetic energy of gas molecules | 11 |

184 | A sample of helium gas is at a temperature of ( 300 mathrm{K} ) and a pressure of 0.5 atm. What is the average kinetic energy of a molecule of a gas? | 11 |

185 | If the average kinetic energy of a molecule of a hydrogen gas at ( 300 mathrm{K} ) is ( mathrm{E} ) then the average kinetic energy of a molecule of a nitrogen gas at the same temperature is: A . ( 7 mathrm{E} ) в. ( E / 14 ) ( c .14 E ) D. ( E / 7 ) ( E . ) | 11 |

186 | The total Kinetic energy of 1 mole of ( N_{2} ) at ( 27^{circ} C ) will be approximately :- A . ( 1500 J ) B . 15633 cal c. ( 1500 mathrm{kcal} ) D. 1500 erg | 11 |

187 | Two glass bulbs of volumes ( 500 mathrm{cm}^{3} ) and ( 200 mathrm{cm}^{3} ) are connected with a narrow tube. Both of them are filled with air at 70mm of ( mathrm{Hg} ) and at ( 17^{circ} mathrm{C} ) and sealed. The bulb of small volume is kept in ice and the other with larger volume is kept in steam. Then find the pressure of the gas in the bulb. A. ( 51 mathrm{mm} ) of ( mathrm{Hg} ) B. 200cm of Hg c. 873mm of Hg D. 200m of Hg | 11 |

188 | If for a gas ( frac{boldsymbol{R}}{boldsymbol{C}_{boldsymbol{v}}}=mathbf{0 . 6 7}, ) then the gas is made up of molecules which are : A. Diatomic B. Monoatomic c. Polyatomic D. Mixture of Diatomic & Polyatomic | 11 |

189 | The ratio of a specific heats of a gas is ( 9 / 7, ) then the number of degrees of freedom of the gas molecules for translation motion is: | 11 |

190 | f ( mathrm{K} ) is the average kinetic energy per atom, find ( x, ) such that ( x=K times 10^{23} ) | 11 |

191 | A gas has an average speed of ( 10 m / s ) and a collision frequency of ( 10 s^{-1} ) What is its mean free path? A. ( 1 m ) в. ( 2 m ) ( c .3 m ) D. ( 0.1 m ) | 11 |

192 | A barometer reads ( 75 mathrm{cm} ) of Hg. When ( 2 mathrm{cc} ) of air at atmpospheric pressure is introduced into the space above the mercury level, the volume of this space becomes 50 cc. The length by which the mercury column descends is A. ( 3 mathrm{cm} ) B. 6 ( mathrm{cm} ) c. ( 1.5 mathrm{cm} ) D. 25 cm | 11 |

193 | A vessel contains a mixture consisting of ( m_{1}-7 g ) of nitrogen ( left(M_{1}=28right) ) and ( m_{2}= ) 11 g of carbon dioxide ( left(M_{2}=44right) ) at temperature ( T-300 K ) and pressure ( P_{0}= ) atm. The density of the mixture is A. ( 1.46 g ) per litre B. ( 2.567 g ) per litre c. ( 3.752 g ) per litre D. ( 4.572 g ) per litre | 11 |

194 | The most probable velocity for monoatomic gas is A ( cdot sqrt{frac{3 k T}{m}} ) в. ( sqrt{frac{8 k T}{pi m}} ) c. ( sqrt{frac{2 k T}{m}} ) D. zero | 11 |

195 | A mercury barometer is known to be defective. It contains a small quantity of air in the space above the mercury. When an accurate barometer reads 770 ( mathrm{mm}, ) the defective one reads ( 760 mathrm{mm} ) and when the accurate one reads 750 ( mathrm{mm}, ) the defective one reads ( 742 mathrm{mm} ) The true atmospheric pressure when the defective barometer reads ( 750 mathrm{mm} ) is A. ( 68 mathrm{cm} ) of ( mathrm{Hg} ) в. ( 79.88 mathrm{cm} ) of ( mathrm{Hg} ) ( c .75 .88 mathrm{cm} ) of ( mathrm{Hg} ) D. 72.15 cm of Hg | 11 |

196 | The mean kinetic energy of a gas molecule is proportional to ( mathbf{A} cdot sqrt{T} ) B . ( T^{3} ) ( c . T ) D. None of the above | 11 |

197 | A thin tube of uniform cross-section is sealed at both ends. It lies horizontally, the middle ( 5 mathrm{cm} ) containing mercury and the two equal ends containing air at the same pressure ( P_{o} . ) When the tube is held at an angle ( 60^{circ} ) with the vertical, the lengths of the air column above and below the mercury are 46 and ( 44.5 mathrm{cm} ) respectively. The pressure ( P_{o} ) in ( mathrm{cm} ) of ( mathrm{Hg} ) is: (The temperature of the system is left at ( 30 mathrm{K} ) A. 80 cm of ( H g ) B. ( 75.4 mathrm{cm} ) of ( mathrm{Hg} ) c. 70 cm of ( H g ) D. 90 cm of ( H g ) | 11 |

198 | Assertion Vibrational energy of diatomic molecule corresponding to each degree of freedom is ( k_{B} T ) Reason For every molecule, vibrational degree of freedom is 2 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 |

199 | A gaseous mixture enclosed in a vessel consists of one ( g ) mole of a gas ( A ) with ( gamma=left(frac{5}{3}right) ) and some amount of gas ( mathrm{B} ) with ( gamma=frac{7}{5} ) at a temperature The gasses ( A ) and ( B ) do not react with each other and are assumed to be ideal Find the number of ( g ) moles of the gas ( B ) if ( gamma ) for the gaseous mixture is ( left(frac{19}{13}right) ) ( A cdot 2 ) ( B .5 ) ( c cdot 4 ) D. 3 | 11 |

200 | A vessel of volume ( V ) contains a mixture of 1 mole of hydrogen and 1 mole of oxygen(both considered as ideal). Let ( f_{1}(v) d v ) denote the fraction of molecules with speed between v and ( (boldsymbol{v}+boldsymbol{d} boldsymbol{v}) ) with ( boldsymbol{f}_{2}(boldsymbol{v}) boldsymbol{d} boldsymbol{v}, ) similarly for oxygen. then ( mathbf{A} cdot f_{1}(v)+f_{2}(v)=f(v) ) obeys the Maxwell’s distribution law B. ( f_{1}(v), f_{2}(v) ) will obey the Maxwell’s distribution law separately C. Neither ( f_{1}(v) ) nor ( f_{2}(v) ) will obey the Maxwell’s distribution law D. ( f_{2}(v) ) and ( f_{1}(v) ) will be the same | 11 |

201 | Significant motion for the molecules of a monoatomic gas corresponds to : A. translatory B. vibratory c. rotatory D. none of these | 11 |

202 | A diatomic gas is heated at certain pressure. What fraction of the heat energy is used to increase the internal energy? A ( .3 / 5 ) B. ( 3 / 7 ) c. ( 5 / 7 ) D. ( 5 / 9 ) | 11 |

203 | At constant temperature and pressure, the volume of a given gas is related to mass as A. Volume is not related to mass B ( cdot v propto frac{1}{m} ) c. ( v propto-frac{1}{m} ) D. ( v propto m ) | 11 |

204 | Pressure of an ideal gas is increased by keeping temperature constant. What is effect on kinetic energy of molecules? A. Increase B. Decrease c. No change D. Cannot be determined | 11 |

205 | State the law of equipartition of energy | 11 |

206 | A barometer reads ( 75 mathrm{cm} ) of mercury. When ( 2.0 mathrm{cm}^{3} ) of air at atmospheric pressure is introduced into space above the mercury level, the volume of the space becomes ( 50 mathrm{cm}^{3} ). The length by which the mercury column descends is A. ( 3 mathrm{cm} ) of ( mathrm{Hg} ) B. ( 6 mathrm{cm} ) of ( mathrm{Hg} ) c. ( 30 mathrm{cm} ) of ( mathrm{Hg} ) D. ( 10 mathrm{cm} ) of ( mathrm{Hg} ) | 11 |

207 | The graph drawn between pressure and volume in Boyle’s law experiment is shown in figure for two different gases. If the same amount of both the gases has been taken, then the relationship between their molecular weights will be A ( . M_{2}<M_{1} ) ( mathbf{B} cdot M_{1}<M_{2} ) ( mathbf{c} cdot M_{1}=M_{2} ) ( mathbf{D} cdot M_{1}^{3}=M_{2} ) | 11 |

208 | If for a gas ( frac{boldsymbol{R}}{boldsymbol{C}_{boldsymbol{V}}}=mathbf{0 . 6 7}, ) this gas is made up of molecules which are. A. Monatomic B. Diatomic c. Polyatomic D. Mixture of diatomic and polyatomic molecules | 11 |

209 | The internal energy of one gram of helium at ( 100 mathrm{K} ) and one atmospheric pressure is? A . 100 B . 1200 J c. 300 D. 500 | 11 |

210 | Estimate the mean free path of a cosmic ray proton in the atmosphere at sea level. Given ( sigma=10^{-26} mathrm{cm}^{2} ) ( mathbf{A} cdot 10^{4} c m ) B. ( 10^{-4} mathrm{cm} ) ( mathbf{c} cdot 10^{6} c m ) D. ( 10^{-6} mathrm{cm} ) | 11 |

211 | Figure shows the variation of the internal energy ( U ) with density ( rho ) of one mole of an ideal monatomic gas for thermodynamic cycle ABCA. Here process ( A B ) is a part of rectangular hyperbola A. process AB is isothermal & net work in cycle is done on gas B. process AB is isothermal & net work in cycle is done by the gas c. process AB is isobaric & net work in cycle is done on the gas D. process AB is adiabatic & net work in cycle is done by gas | 11 |

212 | ( N^{prime} ) moles of a diatomic gas in a cylinder are at a temperature ( ^{prime} boldsymbol{T}^{prime} . ) Heat is supplied to the cylinder such that the temperature remains constant but ( n ) moles of the diatomic gas get converted into monatomic gas.What is the change in the total kinetic energy of the gas? A ( cdot frac{5}{2} n R T ) B. ( frac{1}{2} n R T ) c. 0 D. ( frac{3}{2} n R T ) | 11 |

213 | Match List I and List II List-I List-II a) Barometer e) Charles law b) specific gas constant ( f ) ) ( J m o l e^{-1} K ) -1 c) gas thermometer g) Boyels law d) universal gas constant h) ( operatorname{JKg}^{-1} mathrm{K}^{-1} ) A. a-h,b-e,c-f, d-g. B. a-g, b-h, c-e,d-f. c. a-f, b-g,c-h,d-e. D. ( a-f, b-e, c-h, d-g . ) | 11 |

214 | The kinetic energy of ( 1 g ) molecule of a gas at normal temperature and pressure is : ( mathbf{A} cdot 1.3 times 10^{2} J ) B . ( 2.7 times 10^{2} J ) c. ( 0.56 times 10^{4} J ) D. ( 3.4 times 10^{3} J ) | 11 |

215 | Liquid is filled in a vessel which is kept in a room with temperature ( 20^{circ} mathrm{C} ). When the temperature of the liquid is ( 80^{circ} C ) then it losses heat at the rate of 60 cal/sec.What will be the rate of loss of heat when the temperature of the liquid is ( 40^{circ} mathrm{C} ) A . 180 cal / sec B . 40 cal/sec c. 30 cal/sec D. 20 cal/sec | 11 |

216 | At constant pressure, the heat of formation of a compound is not dependent on temperature, when: ( mathbf{A} cdot Delta C_{p}=0 ) В. ( Delta C_{v}=0 ) ( mathbf{c} cdot Delta C_{p}>0 ) D. ( Delta C_{p}<0 ) | 11 |

217 | The mean free path of a molecule of He gas is a its mean free path along any arbitary coordinate axis will be. | 11 |

218 | The mean free path of the molecule of a certain gas at ( 300 mathrm{K} ) is ( 2.6 times 10^{-5} mathrm{m} ) The collision diameter of the molecule is ( 0.26 mathrm{nm} . ) Calculate (a) pressure of the gas, and (b) number of molecules per unit volume of the gas. B. (a) ( 1.281 times 10^{22} mathrm{m}^{-3} ) (b) ( 5.306 times 10^{3} mathrm{Pa} ) D. (a) 2.56 ( times 10^{23} mathrm{m}^{-3} ) (b) ( 10.612 times 10^{2} mathrm{Pa} ) | 11 |

219 | ( N_{2} ) gas is assumed to behave ideally ( A ) given volume of ( N_{2} ) originally at ( 373 mathrm{k} ) and 0.1013 M pa pressure is adiabatically compressed due to which its temperature rises to ( mathbf{6 7 3} boldsymbol{K}left(boldsymbol{C v}=frac{mathbf{5}}{mathbf{2}} boldsymbol{R}right) ) Which of the following statement(s) is/are correct? This question has multiple correct options A. The change in internal energy is 6235.5 J mole ( ^{-1} ) B. In this case the final internal pressure is equal to the external pressure C. The final pressure of ( N_{2} ) is approximately 0.38 MPa D. The final pressure of ( N_{2} ) is approximately 0.02 Mpa | 11 |

220 | When an ideal diatomic gas is heated at constant pressure, the fraction of the heat energy supplied which increase the internal energy of gas is? ( A cdot frac{2}{5} ) B. ( c cdot frac{3}{7} ) ( D cdot frac{5}{7} ) | 11 |

221 | The mean free path of molecules of a gas (radius ‘r’) is inversely proportional to A ( cdot r^{3} ) В ( cdot r^{2} ) ( c cdot r ) D. ( sqrt{r} ) | 11 |

222 | The mass of hydrogen molecule us ( 3.32 x ) ( 10^{-27} ) kg.If ( 10^{23} ) hydrogen molecules strike per second at ( 2 mathrm{cm}^{2} ) area of a rigid wall at an angle ( 45^{0} ) from the normal and rebound back with speed of ( 1000 mathrm{m} / mathrm{s} ) then the pressure exerted on the wall is A. 2 Pascal B. 2.34 times 10 ( ^{3} ) Pascal c. ( 0.23 times 10^{3} ) Pascal D. 23.4 x 10 ( ^{3} ) Pascal | 11 |

223 | Oxygen is filled in a closed metal jar of volume ( 1.0 times 10^{-3} m^{3} ) at a pressure of ( 1.5 times 10^{5} ) Pa and temperature ( 400 K ) The jar has a small leak in it. The atmospheric pressure is ( 1.0 times 10^{5} mathrm{Pa} ) and the atmospheric temperature is ( 300 K . ) Find the mass of the gas that leaks out by the time the pressure and the temperature inside the jar equalize with the surrounding. | 11 |

224 | In the nuclear fusion reaction, ( _{1}^{2} mathbf{H}+_{1}^{3} ) ( mathbf{H} rightarrow_{2}^{4} H e+n ) given that the repulsive potential energy between the two nuclei is ( 7.7 times 10^{-14} J, ) the temperature at which the gases must be heated to initiate the reaction is nearly [Boltzmann’s constant ( mathbf{k}=mathbf{1 . 3 8} times ) ( left.mathbf{1 0}^{-mathbf{2 3} mathbf{J}} / mathbf{K}right] ) ( mathbf{A} cdot 10^{7} K ) В. ( 10^{5} K ) ( mathbf{c} cdot 10^{3} K ) ( mathbf{D} cdot 10^{9} K ) | 11 |

225 | Two moles of an ideal monoatomic gas at ( 27^{circ} mathrm{C} ) occupies a volume of ( V ). If the gas is expanded adiabatically to the volume ( 2 V ), then the work? | 11 |

226 | There are two vessels of same consisting same no of moles of two different gases at same temperature. One of the gas is ( C H_{4} & ) the other is unknown X. Assuming that all the molecules of ( X ) are under random motion whereas in ( C H_{4} ) except one all are stationary. Calculate ( Z_{1} ) for ( X ) in terms of ( Z_{1} ) of ( C H_{4} . ) Given that the collision diameter for both gases are same ( &left(U_{r m s}right)_{x}=frac{1}{sqrt{6}}(U a v)_{C H_{4}} ) A ( cdot frac{2 sqrt{2}}{3 sqrt{pi}} Z_{1} ) B ( cdot frac{3 sqrt{2}}{2 sqrt{pi}} Z_{1} ) c. ( frac{2 sqrt{3}}{2 sqrt{pi}} Z_{1} ) D. ( frac{4 sqrt{2}}{3 sqrt{pi}} Z_{1} ) | 11 |

227 | For a given gas, which of the following relationships is correct at a given temp? ( mathbf{A} cdot u_{r m s}>u_{a v}>u_{m p} ) B . ( u_{r m s}<u_{a v} u_{a v}<u_{m p} )D. ( u_{r m s} u_{m p} ) | 11 |

228 | A drop of alcohol is introduced into the vaccum space of mercury barometer completely evaporates and then slightly lowers the height of the barometer. If the barometer tube is raised from this position, the height of the barometer will A. fall B. rise C. remains stationery D. falls first and then rises | 11 |

229 | A piece of lead falls from a height of 100m on a fixed non-conducting slab which brings it to rest. The temperature of the lead piece immediately after collision increases by (Sp.heat of lead is ( 30.6 mathrm{cal} / mathrm{kg} /^{0} C ) and ( g=9.8 m / s e c^{2} . ) ( A cdot ) ок в. ( 27^{circ} mathrm{C} ) c. ( 7.62 k ) D. 4.2k | 11 |

230 | Which of the following quantities is the same for all ideal gases at the same temperature? This question has multiple correct options A. The kinetic energy of 1 molecule B. The kinetic energy of ( 1 mathrm{g} ) c. The number of the molecules in 1 mole D. The number of molecules in 1 ( g ) | 11 |

231 | What is the total random translational energy of the molecules in one mole of this gas? | 11 |

232 | The number of degrees of freedom for each atom of a monoatomic gas is : ( A cdot 3 ) B. 5 ( c cdot 6 ) ( D ) | 11 |

233 | One mole of an ideal monoatomic gas is heated at a constant pressure from ( 0^{circ} mathrm{C} ) to ( 100^{circ} mathrm{C} . ) Then the change in the internal energy of the gas is (Given ( boldsymbol{R}=mathbf{8 . 3 2} boldsymbol{J} boldsymbol{m o l}^{-1} boldsymbol{K}^{-1} mathbf{)} ) A ( .0 .83 times 10^{3} J ) в. ( 4.6 times 10^{3} J ) c ( .2 .08 times 10^{3} J ) D. ( 1.25 times 10^{3} J ) | 11 |

234 | Gas exerts pressure on the walls of container because the molecules- A. Are loosing the kinetic energy B. Are getting stuck to the walls C. Are transferring their momentum to walls D. Are accelerated toward walls. | 11 |

235 | One ( k g ) of diatomic gas is at a pressure of ( 8 times 10^{4} N / m^{2} . ) The density of the gas is ( 4 k g / m^{3} . ) What is the energy of the gas due to its thermal motion? A ( .5 times 10^{4} J ) B . ( 6 times 10^{4} J ) c. ( 7 times 10^{4} J ) D. ( 3 times 10^{4} J ) | 11 |

236 | In a certain gas ( frac{2}{5} ) th of the energy of molecules is associated with the rotation of molecules and the rest of it is associated with the motion of the centre of mass. The average translation energy of one such molecule, when the temperature is ( 27^{circ} mathrm{C} ) is given by ( x times ) ( 10^{-23} J ),then find ( x ? ) A . 62 B. 623 c. 6.21 D. 62.1 | 11 |

237 | State whether true or false: Linear molecules have ( 3 N-5 ) vibrational degrees of freedom, whereas non linear molecules have ( 3 N-6 ) vibrational degrees of freedom, where ( N ) is no. of atoms present in a molecule. A. True B. False | 11 |

238 | Assertion Mean free path of a gas molecules varies inversely as density of the gas Reason Mean free path varies inversely as pressure of the gas A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion c. Assertion is correct but Reason is incorrect D. Assertion is incorrect and Reason is correct | 11 |

239 | Root mean square speed of the molecules of ideal gas is ( v ). If pressure is increased two times at constant temperature, the ( r m s ) speed will become: A ( .2 v ) в. ( frac{v}{2} ) c. ( 4 v ) D. | 11 |

240 | A gas thermometer measures the temperature from the variation of pressure of a sample of gas. If the pressure measured at the melting point of lead is 2.20 times the pressure measured at the triple point of water find the melting point of lead. ( mathbf{A} cdot 600 K ) B. ( 420 K ) ( mathbf{c} .790 K ) D. ( 510 K ) | 11 |

241 | A gas has a density of 10 particles ( / m^{3} ) and a molecular diameter of ( 0.1 mathrm{m} ). What is its mean free path? ( mathbf{A} cdot 2.25 m ) в. ( 1 m ) ( c .3 m ) D. ( 0.25 m ) | 11 |

242 | The internal energy of an ideal gas increases during an isothermal process when the gas is A. Expanded by adding more molecules to it B. Expanded by adding more heat to it c. Expanded against zero pressure D. Compressed by doing work on it | 11 |

243 | Boyle’s law holds good for an ideal gas during: A. Isobaric changes B. Isothermal changes c. Isochoric changes D. Isotopic changes | 11 |

244 | A diatomic gas is filled inside a conducting cylinder. Now we push the piston slowly to make volume of gas half of initial. Pick correct statements begin{tabular}{|ccccc|} hline & & & & \ hline & & & & \ ( bullet ) & ( bullet ) & ( bullet ) & ( bullet ) & & \ & ( bullet ) & ( bullet ) & ( bullet ) & & ( bullet ) & ( bullet ) \ ( bullet ) & ( bullet ) & ( bullet ) & ( bullet ) & ( bullet ) \ hline end{tabular} This question has multiple correct options A. Pressure of gas Increases because there is more average change in linear momentum of molecule in each collision B. Pressure force on side wall of container increased C. Pressure force on piston is increased D. More molecules collide with piston per unit time | 11 |

Hope you will like above questions on kinetic theory and follow us on social network to get more knowledge with us. If you have any question or answer on above kinetic theory questions, comments us in comment box.

**help, strategies and expertise**.