A molecule of a gas has six degrees of freedom. Then, the molar s

Previous Year Papers

Download Solved Question Papers Free for Offline Practice and view Solutions Online.

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsMultiple Choice Questions

11.

If m represents the mass of each molecule of a gas and T, its absolute temperature, then the root mean square velocity of the gaseous molecule is proportional to

  • mT

  • m1/2T1/2

  • m-1/2T

  • m-1/2T1/2


Advertisement

12.

A molecule of a gas has six degrees of freedom. Then, the molar specific heat of the gas at constant volume is

  • R2

  • R

  • 3R

  • 2R


C.

3R

We know that,

Specific heat of a gas (At constant volume)

           Cv = f2 × R

where R = number of independent relations
          f = degree of freedom

            = 62 × R

             = 3R


Advertisement
13.

Total number of degrees of freedom of a rigid diatomic molecule is

  • 3

  • 6

  • 5

  • 2


14.

If the pressure and the volume of certain quantity of ideal gas are halved, then its temperature

  • is doubled

  • becomes one-fourth

  • remains constant

  • is halved


Advertisement
15.

The ratio of the molar heat capacities of a diatomic gas at constant pressure to that at constant volume is

  • 72

  • 32

  • 35

  • 75


16.

The temperature at which oxygen molecules have the same root mean square speed as that of hydrogen molecules at 300 K is

  • 600 K

  • 2400 K

  • 4800 K

  • 300 K


17.

Mean free path of a gas molecule is

  • inversely proportional to number of molecules per unit volume

  • inversely proportional to diameter of the molecule

  • directly proportional to the square root of the absolute temperature

  • directly proportional to the molecular mass


18.

In a certain region of space there are only 5 molecules per cm3 on an average. The temperature there is 3 K.The pressure of this dilute gas is  (k = 1.38 x 10-23 J/K)

  • 20.7 × 10-17 N/m2

  • 15.3 × 10-15 N/m2

  • 2.3 × 10-10 N/m2

  • 5.3 × 10-5 N/m2


Advertisement
19.

The value of PVT for one mole of an ideal gas is nearly equal to

  • 2 J mol-1 K-1

  • 8.3 mol-1 K-1

  • 4.2 mol-1 K-1

  • 2 cal mol-1 K-1


20.

If P is the pressure, V the volume, R the gas constant, k the Boltzmann constant and T the absolute temperature, then the number of molecules in the given mass of the gas is given by

  • PVRT

  • PVkT

  • PRT

  • pV


Advertisement