All gases deviate from gas laws at

What is free path and mean free path?

If $n$ is the number density and $d$ is the diameter of the molecule,then the average distance covered by a molecule between two successive collisions (i.e. mean free path) is represented by :

The diameter of an oxygen molecule is $2.94 \times 10^{-10} \ m$. The van der Waals gas constant '$b$' in $m^3/mol$ is:

$A$ fixed amount of nitrogen gas ($1$ mole) is taken and subjected to pressure and temperature variations. The experiment is performed at high pressures and various temperatures. The results obtained are shown in the figure. The correct variation of $PV/RT$ with $P$ for nitrogen gas at high temperatures will be exhibited by:

The change in volume $V$ with respect to an increase in pressure $P$ has been shown in the figure for a non-ideal gas at four different temperatures ${T_1}, {T_2}, {T_3}$ and ${T_4}$. The critical temperature of the gas is