$C_p$ and $C_v$ are specific heats at constant pressure and constant volume respectively. It is observed that <br> $C_p - C_v$ = a for hydrogen gas <br> $C_p - C_v$ = b for nitrogen gas <br> The correct relation between a and b is :

Question

( A ) $a = 28\; b$
( B ) $a = 14\;b$
( C ) $a = b$
( D ) $a = \frac{1}{14}b$