For a rigid diatomic molecule,the universal gas constant $R = n C_P$,where $C_P$ is the molar specific heat at constant pressure and $n$ is a number. Hence,$n$ is equal to

If the degree of freedom of a gas is $f,$ then the ratio of two specific heats ${C_P}/{C_V}$ is given by

When an ideal diatomic gas is heated at constant pressure,the fraction of the heat utilized to increase the internal energy of the gas is

The molar specific heat of a gas as given from the kinetic theory is $\frac{5}{2} R$. If it is not specified whether it is $C_P$ or $C_V$,one could conclude that the molecules of the gas

$c_P$ and $c_V$ are specific heats at constant pressure and constant volume respectively. It is observed that
$c_P - c_V = a$ for hydrogen gas
$c_P - c_V = b$ for nitrogen gas
The correct relation between $a$ and $b$ is

The molar specific heat at constant pressure for a monoatomic gas is