Answer
a. All gases have the same average kinetic energy.
b. $H_2$, $O_2$, $Cl_2$, $Xe$
c. We can raise $O_2$ and $H_2$ to relative temperatures such that the difference between $O_2$ and $H_2$ masses are compensated by a greater average kinetic energy for $O_2$.
Work Step by Step
a. Temperature is proportional to average kinetic energy. Therefore, since all of these gaseous samples are at the same temperature of 273 K, all gaseous samples possess the same kinetic energy.
b. Average velocity is indirectly proportional to atomic mass. Therefore, a lower atomic mass results in a greater average velocity. The order of gases of increasing atomic mass is $H_2$, $O_2$, $Cl_2$, $Xe$. Therefore, the order of increasing average velocity is also $H_2$, $O_2$, $Cl_2$, $Xe$.
c. The difference between the masses of $O_2$ and $H_2$ can be compensated by increasing the temperature and average kinetic energy of the $O_2$ gas. Therefore, $O_2$ is able to reach the same average velocity as $H_2$.
