# Kinetic Theory of Gases Obj-2 HC Verma Solutions Vol-2 Ch-24

Kinetic Theory of Gases Obj-2 HC Verma Solutions Vol-2 Ch-24 Concept of Physics for Class-12. Step by Step Solutions of Objective -2 (MCQ-2) Questions of Chapter-24 Kinetic Theory of Gases (Concept of Physics) .Visit official Website CISCE for detail information about ISC Board Class-12 Physics.

## Kinetic Theory of Gases Obj-2 (MCQ-2) HC Verma Solutions Ch-24 Vol-2 Concept of Physics for Class-12

 Board ISC and other board Publications Bharti Bhawan Publishers Chapter-24 Kinetic Theory of Gases Class 12 Vol 2nd writer HC Verma Book Name Concept of Physics Topics Solution of Objective-2 (MCQ-2) Questions Page-Number 33, 34

-: Select Topics :-

Objective-I

Objective-II

Exercise

Kinetic Theory of Gases Obj-2 (MCQ-2) HC Verma

### HC Verma Solutions of Ch-24  Vol-2 Concept of Physics for Class-12

(Page-33)

#### Question-1 :-

Consider a collision between an oxygen molecule and a hydrogen molecule in a mixture of oxygen and hydrogen kept at room temperature. Which of the following are possible?
(a) The kinetic energies of both the molecules increase.
(b) The kinetic energies of both the molecules decrease.
(c) kinetic energy of the oxygen molecule increases and that of the hydrogen molecule decreases.
(d) The kinetic energy of the hydrogen molecule increases and that of the oxygen molecule decreases.

The options (c) and (d) are correct

Explanation:

According to Kinetic theory, postulates collision between molecules are elastic. This means that kinetic energy after any collision is conserved because while one one gains kinetic energy, another loses it. Both options, (c) and (d) consider the conservation of kinetic energy in the collision.

(Page-34)

#### Question-2 :-

Consider a mixture of oxygen and hydrogen kept at room temperature. As compared to a hydrogen molecule an oxygen molecule hits the wall

(a) with greater average speed

(b) with smaller average speed

(c) with greater average kinetic energy

(d) with smaller average kinetic energy

The option (b) with smaller average speed is correct

Explanation:

The average speed of molecules is given by √8kT/πm .

We observe that greater the mass, lesser is the average speed of the molecule. Since an oxygen molecule is heavier than a hydrogen molecule, the oxygen molecule will hit the wall with smaller average speed.

#### Question-3 :-

Which of the following quantities is zero on an average for the molecules of an ideal gas in equilibrium?

(a) Kinetic energy

(b) Momentum

(c) Density

(d) Speed

The option (b) Momentum is correct

Explanation:

The molecules move in all possible directions in an ideal gas at equilibrium. Since momentum is a vector quantity for every direction of motion of the molecules, there exists an opposite direction of motion of the other. Hence, the average momentum is zero for an ideal gas at equilibrium.

The average momentum of a molecule in a sample of an ideal gas depends on

(a) temperature

(b) number of moles

(c) volume

(d) none of these.

The option (d) none of these. is correct

Explanation:

Average momentum of a gas sample is zero, so it does not depend upon any of these parameters.

The option (d) nature of the gas. is correct

Explanation:

In  an  ideal  gas,   the  equation  of  state  is  given  by  PV=nRT

Multiplying  both  sides  by  mass  of  the  gas  M,   we  get

Now,   n N_A   gives  the  total  number  of  molecules  of  the  gas .

Also,

gives  the  mass  of  a  single  molecule .

Hence,

is  the  mass  of  a  single  molecule  of  the  gas,   Molecular  mass  is  a  property  of  the  gas .

—: End of Kinetic Theory of Gases Obj-2 (mcq-2) HC Verma Solutions Vol-2 Chapter-24 :–