Which of the following statement(s) is/are correct about a fixed mass of gas compressed in an inexpansible container

I. The average speed of the molecules increases

II. The temperature of the gas increases

III. The molecules hit the walls of the container more often than before the compression

A. I only
B. I and II only
C. I, II, and III only
D. I and III

Correct Answer:

Option C = I, II, and III only

Explanation

The kinetic-molecular theory of gases assumes that ideal gas molecules:

(1) are constantly moving;

(2) have negligible volume;

(3) have negligible intermolecular forces;

(4) undergo perfectly elastic collisions; and

(5) have an average kinetic energy proportional to the ideal gas’s absolute temperature.