A container is filled with a mixture of helium and oxygen gases. A thermometer in the container indicates that the temperature is 22.° C. Which gas molecules have the greater average kinetic energy?
A) It is the same for both because the temperatures are the same.
B) The oxygen molecules do because they are diatomic.
C) The oxygen molecules do because they are more massive.
D) The helium molecules do because they are less massive.
E) The helium molecules do because they are monatomic.

Question

Quizplus · Accepted Answer

The average kinetic energy of gas molecules in a mixture is determined by the temperature of the mixture. Since both helium and oxygen gases are at the same temperature (22°C), their average kinetic energies are the same, regardless of their molecular masses or whether they are monatomic or diatomic.

A Container Is Filled with a Mixture of Helium and Oxygen