The postulates of the kinetic molecular theory are related to what?

Two gases $A$ and $B$ are released from the two ends of a tunnel of length $100 \ m$. $A$ travels $40 \ m$ before meeting the gas $B$ in the tunnel. If the molecular weight of $B$ is $18$, what is the molecular weight of $A$ (in $.5$)?

The Kelvin temperature of an ideal gas is

What is the average kinetic energy per molecule of an ideal gas in $SI$ units at $25 \, ^\circ C$?

What is the average translational kinetic energy of a gas molecule?

According to the kinetic theory of gases,which of the following statements are correct?
$A$. Collisions are always elastic.
$B$. Heavier molecules transfer more momentum to the wall of the container.
$C$. Only a small number of molecules have very high velocity.
$D$. Between collisions,the molecules move in straight lines with constant velocities.