Skip to main content
Back to KINETIC THEORY OF GASES

Your Progress

0 / 290 Answered
0
Correct
0
Incorrect
0%
Accuracy
JEE • PHYSICS • KINETIC THEORY OF GASES

Kinetic theory of gases practice · Mixed difficulty

Try a question, then open “View answer” to check it. Sign in to submit answers and save progress.

Practice format and chapter quiz

These sets use single-correct-answer MCQs. They do not cover every JEE Main or JEE Advanced question format and are not full-length mock papers.

Take a chapter quiz →
Showing 241-270 of 290 questions
241 Medium
241 of 290
Understanding +4 | -1
In the expression for VrmsV_{r m s} of a mixture of 2 gases at same temperature, Vrms=3RTMV_{r m s}=\sqrt{\frac{3 R T}{M}}, the molecular weight M\mathrm{M} is
View answer and explanation
Correct option: B
Harmonic mean of molecular weights
Option B is correct because the molecular weight M in the Vrms expression for a gas mixture is the harmonic mean of the individual molecular weights.
242 Medium
242 of 290
Understanding +4 | -1
With increase in pressure at constant temperature, rms speed of gases
View answer and explanation
Correct option: C
Remains same
Option C (Remains same) is correct because the RMS speed of gas molecules depends only on temperature, and the temperature is held constant.
243 Medium
243 of 290
Understanding +4 | -1
Pressure of a gas at constant volume is proportional to
View answer and explanation
Correct option: D
Total internal energy of the gas
The correct answer is D because at constant volume, the pressure of a gas is directly proportional to its total internal energy.
244 Medium
244 of 290
Remembering +4 | -1
For a real gas (van der Waal’s gas)
View answer and explanation
Correct option: B
Critical temperature is a/Rba/Rb
Option A (Boyle temperature is a/Rba/Rb) is correct because the Boyle temperature for a van der Waals gas is given by TB=a/RbT_B = a/Rb.
245 Medium
245 of 290
Application +4 | -1
Calculate the ratio of rms speeds of oxygen gas molecules to that of hydrogen gas molecules kept at the same temperature.
View answer and explanation
Correct option: A
1:41:4
Option A (1:41:4) is correct because the rms speed is inversely proportional to the square root of the molar mass.
246 Medium
246 of 290
Understanding +4 | -1
The average kinetic energy per mole of hydrogen at given temperature is
View answer and explanation
Correct option: A
equal of that of oxygen
Option A (equal of that of oxygen) is correct because the average kinetic energy per mole of an ideal gas depends only on the temperature and is independent of the type of gas.
247 Medium
247 of 290
Remembering +4 | -1
The number of translational degrees of freedom for a diatomic gas is
View answer and explanation
Correct option: B
3
Option B (3) is correct because a diatomic gas, like any gas, can move freely in three-dimensional space, thus having 3 translational degrees of freedom.
248 Medium
248 of 290
Understanding +4 | -1
If the earth did not have atmosphere, the temperature would be
View answer and explanation
Correct option: A
Less
Option B (irreversible adiabatic) is correct because the bursting of a balloon is a rapid, uncontrolled expansion where no heat is exchanged with the surroundings.
249 Medium
249 of 290
Analyzing +4 | -1
Assertion: A gas is kept in an insulated cylinder with a movable piston, in compressed state. As the piston is released, temperature of the gas decreases.
Reason: According to the kinetic theory of gas, a molecule colliding with the piston must rebound with less speed than it had before the collision. Hence average speed of the molecules is reduced.
View answer and explanation
Correct option: A
If both assertion and reason are true and reason is the correct explanation of the assertion
The assertion and reason are both true, and the reason is the correct explanation of the assertion because the gas does work on the piston, reducing the average speed of the molecules and thus the temperature.
250 Medium
250 of 290
Understanding +4 | -1
The temperature of a gas is held constant, while its volume is decreased. The pressure exerted by its volume is decreased. The pressure exerted by the gas on the walls of the container increases, because its molecules
View answer and explanation
Correct option: A
Strike the walls more frequently
Option A (Strike the walls more frequently) is correct because decreasing the volume at constant temperature increases the frequency of molecular collisions with the container walls.
251 Medium
251 of 290
Application +4 | -1
Find the ratio of specific heat at constant pressure to the specific heat constant volume for NH3N{H_3}
View answer and explanation
Correct option: C
1.28
Option C (1.28) is correct because the ratio of specific heats for a polyatomic gas like NH3 is less than 1.33 and closer to 1.28 considering vibrational degrees of freedom.
252 Easy
252 of 290
Remembering +4 | -1
The critical volume of a gas obeying van der Waals' equation is
View answer and explanation
Correct option: C
3b3 b
Option C (3 b) is correct because the critical volume (VcV_c) in the van der Waals equation of state is given by Vc=3bV_c = 3b, where 'b' is the van der Waals parameter related to the volume of the gas molecules.
253 Medium
253 of 290
Application +4 | -1
For a gas at 300 K300 \mathrm{~K} temperature energy is 300 J300 \mathrm{~J} and speed is 300 m/300 \mathrm{~m} / sec. If temperature is made 2 times of initial then find out the final energy and speed.
View answer and explanation
Correct option: A
3002 m/sec300 \sqrt{2} \mathrm{~m} / \mathrm{sec}
Option A (3002 m/sec300 \sqrt{2} \mathrm{~m} / \mathrm{sec}) is correct because the final speed is 3002 m/sec300 \sqrt{2} \mathrm{~m} / \mathrm{sec}, calculated by using the relation between speed and temperature.
254 Medium
254 of 290
Understanding +4 | -1
The value of molar specific heat at constant volume for 1 mole of polyatomic gas having nn number of degrees of freedom at temperature T KT \, K is (here, R=R= universal gas constant)
View answer and explanation
Correct option: B
nR2\frac{n R}{2}
Option B (nR2\frac{n R}{2}) is correct because the molar specific heat at constant volume for a polyatomic gas with n degrees of freedom is given by nR2\frac{nR}{2}.
255 Medium
255 of 290
Understanding +4 | -1
Molecules of a gas behave like
View answer and explanation
Correct option: C
Perfectly elastic rigid sphere
Option C (Perfectly elastic rigid sphere) is correct because the kinetic theory of gases assumes that gas molecules undergo perfectly elastic collisions and are rigid spheres.
256 Medium
256 of 290
Application +4 | -1
Two gases occupy two containers A\mathrm{A} and B\mathrm{B} the gas in A\mathrm{A}, of volume 0.10 m30.10 \mathrm{~m}^3, exerts a pressure of 1.40MPa1.40 \mathrm{MPa} and that in B\mathrm{B} of volume 0.15 m30.15 \mathrm{~m}^3 exerts a pressure 0.7MPa0.7 \mathrm{MPa}. The two containers are united by a tube of negligible volume and the gases are allowed to intermingle. Then if the temperature remains constant, the final pressure in the container will be (in MPa\mathrm{MPa} )
View answer and explanation
Correct option: B
0.98
Option B (0.98 MPa) is correct because the final pressure is calculated using Boyle's law, considering the combined volume and constant temperature.
257 Medium
257 of 290
Analyzing +4 | -1
Assertion : Vibrational energy of particle at temperature T is kT.

Reason : For every particle, vibrational degree of freedom is 2.
View answer and explanation
Correct option: D
If both Assertion & Reason are False
Option D is correct because the vibrational energy of a particle at temperature T is not simply kT, and a particle can have more or less than 2 vibrational degrees of freedom depending on the molecular structure.
258 Medium
258 of 290
Understanding +4 | -1
Increase in temperature of a gas filled in a container would lead to:
View answer and explanation
Correct option: B
Increase in its kinetic energy
Option B is correct because increasing the temperature of a gas increases the average kinetic energy of its molecules.
259 Medium
259 of 290
Application +4 | -1
If three molecules of oxygen at 27∘C27^{\circ} \mathrm{C} have velocities 0.5 km/s,1 km/s0.5 \mathrm{~km} / \mathrm{s}, 1 \mathrm{~km} / \mathrm{s} and 2 km/s2 \mathrm{~km} / \mathrm{s} respectively. Then their root mean square speed will be
View answer and explanation
Correct option: B
1.32 km/s1.32 \mathrm{~km} / \mathrm{s}
Option B (1.32 km/s) is correct because the root mean square speed is calculated as the square root of the average of the squares of the velocities.
260 Medium
260 of 290
Understanding +4 | -1
Speed of sound in a gas is vv and r.m.s.r.m.s. velocity of the gas molecules is c.c. The ratio of vv to cc is
View answer and explanation
Correct option: D
γ3\sqrt {\frac{\gamma }{3}}
Option D (γ3\sqrt{\frac{\gamma}{3}}) is correct because it represents the ratio of the speed of sound in a gas to the RMS velocity of the gas molecules.
261 Medium
261 of 290
Understanding +4 | -1
For Boyle’s law to hold good, the gas should be
View answer and explanation
Correct option: B
Perfect and of constant mass and temperature
Boyle's law states that for a perfect gas with constant mass and temperature, pressure and volume are inversely proportional.
262 Medium
262 of 290
Understanding +4 | -1
A cylinder rolls without slipping down an inclined plane, the number of degrees of freedom it has, is
View answer and explanation
Correct option: A
2
Option A is correct because a cylinder rolling without slipping on an inclined plane has one translational and one rotational degree of freedom.
263 Medium
263 of 290
Understanding +4 | -1
What is the average velocity of the molecules of an ideal gas?
View answer and explanation
Correct option: D
Zero
Option D (Zero) is correct because the average velocity considers the vector sum of all molecular velocities, which cancels out to zero in an ideal gas.
264 Medium
264 of 290
Application +4 | -1
The velocity of 4 gas molecules are given by 1 km/s, 3 km/s, 5 km/s and 7 km/s. Calculate the difference between average and rms velocity.
View answer and explanation
Correct option: C
0.583
Option A ( - 5 < a < 2) is correct because the given inequality holds for all real x if the discriminant of the quadratic is negative, leading to this range for a.
265 Medium
265 of 290
Understanding +4 | -1
According to the kinetic theory of gases, at absolute temperature
View answer and explanation
Correct option: C
Molecular motion stops
The correct answer is C (Molecular motion stops) because at absolute zero temperature, the kinetic energy of the molecules becomes zero, resulting in no motion.
266 Medium
266 of 290
Application +4 | -1
At identical temperatures, the rms speed of hydrogen molecules is 4 times that for oxygen molecules. In a mixture of these in mass ratio H2:O2=1:8\mathrm{H}_2: \mathrm{O}_2=1: 8, the rms speed of all molecules is n\mathrm{n} times the rms speed for O2\mathrm{O}_2 molecules, where n\mathrm{n} is
View answer and explanation
Correct option: D
(11)1/2(11)^{1 / 2}
Option D (11\sqrt{{11}}) is correct because it correctly calculates the root mean square speed of the mixture based on the number ratio and individual rms speeds.
267 Medium
267 of 290
Analyzing +4 | -1
The internal energy (U)\left( U \right), pressure (p)\left( p \right) and volume (V)\left( V \right) of an ideal gas are related as U=3pV+4U = 3pV + 4. The gas is
View answer and explanation
Correct option: B
polyatomic only
Option B is correct because the internal energy equation implies a degree of freedom greater than 6, indicating a polyatomic gas.
268 Medium
268 of 290
Understanding +4 | -1
A polyatomic gas with n degrees of freedom has a mean energy per molecule given by
(NN is Avogadro’s number)
View answer and explanation
Correct option: C
nkT2\frac{{nkT}}{2}
Option C is correct because the mean energy per molecule for a polyatomic gas with n degrees of freedom is given by nkT2\frac{{nkT}}{2}.
269 Medium
269 of 290
Understanding +4 | -1
A flask contains Hydrogen and Argon in the ratio 2:12: 1 by mass. The temperature of the mixture is 30∘C30^{\circ} \mathrm{C}. The ratio of average kinetic energy per molecule of the two gases ( K\mathrm{K} argon/ K\mathrm{K} hydrogen) is:
(Given : Atomic Weight of Ar=39.9\mathrm{Ar}=39.9 )
View answer and explanation
Correct option: B
1
Option B (1) is correct because the average kinetic energy per molecule depends only on temperature, which is the same for both gases.
270 Medium
270 of 290
Understanding +4 | -1
Statement-I: Boltzmann's constant is a gas constant for 1 molecule of a gas
Statement-II: Universal gas constant is a gas constant for 1 mole of a gas
View answer and explanation
Correct option: A
Statement-I and statement-II are true
Option A (Statement-I and statement-II are true) is correct because Boltzmann's constant is the gas constant for one molecule, and the universal gas constant is for one mole.
Revision notes and key takeaways

Review KINETIC THEORY OF GASES in your textbook or class notes, then use this set to check your understanding.

Showing 241-270 of 290 questions
0 /290
0✓ 0✗
0% Accuracy
Type at least 2 characters or jump directly:
🔓

Save your learning progress

Sign in with a free account to save your practice answers and quiz results, then return to them when you revise.