The specific heats, $\mathrm{C}_{\mathrm{P}}$ and $\mathrm{C}_{\mathrm{V}}$ of a gas of diatomic molecules, A , are given (in units of $\mathrm{J} \mathrm{mol}^{-1} \mathrm{~K}^{-1}$ ) by 29 and 22 , respectively. Another gas of diatomic molecules, B, has the corresponding values 30 and 21 . If they are treated as ideal gases, then :