Kinetic Theory · Question 3

An ideal gas at pressure P and temperature T is expanding such that PT3 = constant. The coefficient of volume expansion of the gas is .

1. 2T
2. 1T
3. 4T
4. 3T

One gas of n1 mole of molecules at temperature T1, volume V1, and pressure P1, and another gas of n2 mole of molecules at temperature T2, volume V2, and pressure P2, are mixed resulting in pressure P and volume V of the mixture. The temperature of the mixture is .

1. (T1+T2)2
2. T1T2PVT2P1V1+T1P2V2
3. (T2P1V1+T1P2V2)T1T2PV
4. |T1-T2|2

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Choose the correct answer from the options given below :

1. Both (A) and (R) are true and (R) is the correct explanation of (A)
2. Both (A) and (R) are true but (R) is NOT the correct explanation of (A)
3. (A) is true but (R) is false
4. (A) is false but (R) is true

A mixture of carbon dioxide and oxygen has volume 8310 cm3, temperature 300 K, pressure 100 kPa and mass 13.2 g. The number of moles of carbon dioxide and oxygen gases in the mixture respectively are . (Assume both carbon dioxide and oxygen gases behave like ideal gases) [R = 8.31 J/mol K]

1. 0.15 and 0.18
2. 0.25 and 0.08
3. 0.21 and 0.12
4. 0.13 and 0.20

The mean free path of a molecule of diameter 5 10-10 m at the temperature 41 C and pressure 1.38 105 Pa, is given as m. (Given kB = 1.38 10-23 J/K).

1. 2 2 10-10
2. 10 2 10-8
3. 2 2 10-8
4. 2 10-8

Consider two boxes containing ideal gases A and B such that their temperatures, pressures and number densities are same. The molecular size of A is half of that of B and mass of molecule A is four times that of B. If the collision frequency in gas B is 32 1018 /s then collision frequency in gas A is /s.

1. 8 1018
2. 2 1018
3. 32 1018
4. 4 1018

An insulated cylinder of volume 60 cm3 is filled with a gas at 27 and 2 atmospheric pressure. Then the gas is compressed making the final volume as 20 cm3 while allowing the temperature to rise to 77 . The final pressure is atmospheric pressure.

The r.m.s. speed of oxygen molecules at 47 is equal to that of the hydrogen molecules kept at . (Mass of oxygen molecule/mass of hydrogen molecule = 32/2)

1. -100
2. -253
3. -20
4. -235

Match the List I with List II Choose the correct answer from the options given below:

1. A-III, B-IV, C-I, D-II
2. A-II, B-IV, C-I, D-III
3. A-IV, B-II, C-III, D-I
4. A-III, B-II, C-IV, D-I

The helium and argon are put in the flask at the same room temperature (300 K). The ratio of average kinetic energies (per molecule) of helium and argon is: (Given: Molar mass of helium = 4 g/mol, Molar mass of argon = 40 g/mol)

1. 1 : 10
2. 10 : 1
3. 1 : 10
4. 1 : 1