Which of the following can be most easily liquefied? (Value of $a$ for $NH_3 = 4.17, CO_2 = 3.59, SO_2 = 6.71, Cl_2 = 6.49$)

Under which conditions does a real gas show maximum deviation from ideal gas behavior?

In van der Waals equation of state,the constant $b$ is a measure of

Which statement is correct regarding a real gas?

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: $CH_4, O_2, H_2$

The Van der Waals constants '$a$' and '$b$' are related to which of the following respectively?