Question

Which one of the following statements is not true about the effect of an increase in temperature on the distribution of molecular speeds in a gas?

• A. The area under the distribution curve remains same as under the lower temperature.
• B. The distribution becomes broader.
• C. The fraction of the molecules increases with the most probable speed.
• D. The most probable speed increases.

Answer 1

Answer: (C)

The fraction of the molecules increases with the most probable speed.

Distribution of molecules (N) with velocity ($u$) at two temperature $T_1$ and $T_2$ ($T_2$ > $T_1$) is show in the diagram.
At both temperatures, with increase in velocity the distribution of molecules first increases then reaches a maximum value and finally it decreases.