Van der Waal's equation $\left[ p + \frac{a}{V^2} \right] (V - b) = nRT$ is applicable for

The pressure exerted by $5 \, mol$ of a real gas in a $1 \, L$ container at $47 \, ^oC$ is ............. $atm$. $\left( a = 3.592 \, atm \, L^2 \, mol^{-2}, b = 0.0427 \, L \, mol^{-1} \right)$

At a temperature of $27\,^{\circ}C$,if the volume of $2\, \text{moles}$ of $NH_3$ gas is $5\, L$ according to the van der Waals equation,what will be its pressure in $atm$? ($a = 4.17$,$b = 0.03711$)

Calculate the compressibility factor for $SO_2$,if $1 \ mol$ of it occupies $0.35 \ L$ at $300 \ K$ and $50 \ atm$ pressure.

At very low pressure,if the molar volume of $CO_2$ is constant,its compressibility factor is ..........

For real gases,the relation between $p$,$V$,and $T$ is given by the van der Waals equation:
$(p + \frac{an^2}{V^2})(V - nb) = nRT$
Where $a$ and $b$ are van der Waals constants,$nb$ is approximately equal to the total volume of the molecules of a gas,and $a$ is the measure of the magnitude of intermolecular attraction.
$(i)$ Arrange the following gases in the increasing order of $b$. Give reason: $O_2, CO_2, H_2, He$
$(ii)$ Arrange the following gases in the decreasing order of magnitude of $a$. Give reason: $CH_4, O_2, H_2$