Question

According to the kinetic molecular theory of gases, the average kinetic energy of gas molecules:

• A. Increases with increase in pressure
• B. Decreases with increase in volume
• C. Is directly proportional to the absolute temperature
• D. Is the same for all gases at the same volume

Hint:

In kinetic theory, the average kinetic energy depends only on temperature.

Answer 1

The Correct Option is C

Step 1: Recall the result
For gas molecules the average kinetic energy is \(\bar{E}_k=\frac{3}{2}k_BT\) per molecule.
It depends only on the absolute temperature.

Step 2: Check each option
(A) Pressure can rise with no change in \(T\), so \(\bar{E}_k\) does not depend on it.
(B) Volume changes do not alter \(\bar{E}_k\) at fixed \(T\).
(C) \(\bar{E}_k\propto T\), which is true.
(D) Volume has no role. The kinetic energy is the same for all gases at the same temperature, not at the same volume.

Final Answer:
Option (C) is correct. \[ \boxed{\text{(C)}} \]