Absolute zero is the temperature at which:

$A$ gas is contained in a vessel at pressure $P_0$. If the mass of all molecules is halved and their speed is doubled,what will be the final pressure?

The translational kinetic energy of the molecules of a gas at absolute temperature $T$ can be doubled by

If the number of hydrogen molecules is twice the number of oxygen molecules at the same temperature,what is the ratio of their total kinetic energies? (Hydrogen : Oxygen)

Obtain an expression for the momentum of a gas transferred to the walls of a container in time $\Delta t$.

$A$ balloon has $5.0$ $g$ mole of helium at $7^{\circ} C$. Calculate
$(a)$ the number of atoms of helium in the balloon,
$(b)$ the total internal energy of the system.