Thank you for reporting, we will resolve it shortly
Q.
At high pressures, the compressibility factor $ z $ is equal to
Uttarkhand PMTUttarkhand PMT 2007
Solution:
$P+\frac{a}{V^{2}}(V-d)=R T$
At high pressure $b$ can not be neglected in comparison to $V$.
Further though $V$ becomes small, $\frac{a}{V^{2}}$
is large but as $P$ is very high, $\frac{a}{V^{2}}$.
Can be neglected in comparison to $P$. Hence,
$P(V-d)=R T $ or $ P V=R T+P b$
or $\frac{P V}{R T}=1+\frac{P b}{R T} $
i.e, $z=1+\frac{P b}{R T}$