Kinetic Theory

The ratio of vapour densities of two gases at the same temperature is 425, then the ratio of r.m.s. velocities will be :

1. 52
2. 254
3. 425
4. 25

The kinetic energy of translation of the molecules in 50 g of CO2 gas at 17 is :

1. 4205.5 J
2. 3582.7 J
3. 3986.3 J
4. 4102.8 J

For a diatomic gas, if 1= ( CpCv ) for rigid molecules and 2= ( CpCv ) for another diatomic molecules, but also having vibrational modes. Then, which one of the following options is correct? (Cp and Cv are specific heats of the gas at constant pressure and volume)

1. 2< 1
2. 2> 1
3. 2= 1
4. 2 2= 1

The temperature of a gas is -78 and the average translational kinetic energy of its molecules is K. The temperature at which the average translational kinetic energy of the molecules of the same gas becomes 2 K is :

1. -78
2. 127
3. -39
4. 117

A mixture of one mole of monoatomic gas and one mole of a diatomic gas (rigid) are kept at room temperature (27 ). The ratio of specific heat of gases at constant volume respectively is:

1. 32
2. 35
3. 75
4. 53

Given below are two statements : In the light of the above statements, choose the correct answer from the options given below :

1. Statement I is false but Statement II is true
2. Both Statement I and Statement II are true
3. Statement I is true but Statement II is false
4. Both Statement I and Statement II are false

A sample contains mixture of helium and oxygen gas. The ratio of root mean square speed of helium and oxygen in the sample, is :

1. 12 2
2. 14
3. 2 21
4. 132

Energy of 10 non rigid diatomic molecules at temperature T is :

1. 35 RT
2. 72 RT
3. 70 KBT
4. 35 KBT

If the collision frequency of hydrogen molecules in a closed chamber at 27 is Z, then the collision frequency of the same system at 127 is :

1. 32Z
2. 2 3Z
3. 34Z
4. 43Z

If n is the number density and d is the diameter of the molecule, then the average distance covered by a molecule between two successive collisions (i.e. mean free path) is represented by :

1. 1 2n d2
2. 1 2n2 2d2
3. 1 2n d2
4. 2n d2