Liquids diffuse more slowly than gases because.....

For a fixed number of moles of a gas at constant volume,the pressure of the gas increases with a rise in temperature due to:

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

The mass of molecule $A$ is half the mass of molecule $B$. The $rms$ speed of $A$ is twice the $rms$ speed of $B$. If two samples of $A$ and $B$ contain the same number of molecules and are taken in two separate containers of equal volume,what will be the ratio of the pressure of $A$ to the pressure of $B$ $(P_A/P_B)$?

Assertion $(A)$ At $300 \ K$, kinetic energy of $16 \ g$ of methane is equal to the kinetic energy of $32 \ g$ of oxygen.
Reason $(R)$ At constant temperature, kinetic energy of one mole of all gases is equal.

The diffusion coefficient of an ideal gas is proportional to its mean free path and mean speed. The absolute temperature of an ideal gas is increased $4$ times and its pressure is increased $2$ times. As a result,the diffusion coefficient of this gas increases $x$ times. The value of $x$ is