The mean energy of a molecule of an ideal gas is

Vessel $A$ is filled with hydrogen while vessel $B,$ whose volume is twice that of $A,$ is filled with the same mass of oxygen at the same temperature. The ratio of the mean kinetic energies of hydrogen and oxygen is

Estimate the average thermal energy of a helium atom at:
$(i)$ room temperature $(27^{\circ} C)$,
$(ii)$ the temperature on the surface of the Sun $(6000\; K)$,
$(iii)$ the temperature of $10$ million kelvin (the typical core temperature in the case of a star).

If $E$ is the kinetic energy per mole of an ideal gas and $T$ is the absolute temperature,then the universal gas constant is given as

The total internal energy of $4$ moles of a diatomic gas at a temperature of $27^{\circ} C$ is (Universal gas constant $R = 8.31 \ J \ mol^{-1} \ K^{-1}$) (in $kJ$)

$A$ gas exerts pressure on the walls of a container because the molecules .......