Chemistry - Real Gas Question with Solution | TestHub

$\mathrm{P}\left(\mathrm{V}-\mathrm{b}\right)=\mathrm{R}\mathrm{T}$
$\Rightarrow \mathrm{P}\mathrm{V}-\mathrm{P}\mathrm{b}=\mathrm{R}\mathrm{T}$
$\Rightarrow \frac{\mathrm{P}\mathrm{V}}{\mathrm{R}\mathrm{T}}=\frac{\mathrm{P}\mathrm{b}}{\mathrm{R}\mathrm{T}}+1$
$\Rightarrow \mathrm{Z}=1+\frac{\mathrm{P}\mathrm{b}}{\mathrm{R}\mathrm{T}}$
Hence,$\mathrm{Z}>1$at all pressures.
This means, repulsive tendencies will be dominant when interatomic distance are small. This means, interatomic potential is never negative but becomes positive at small interatomic distances.