The compressibility factor $(Z)$ of a gas is greater than unity at $1 \, atm$ and $273 \, K$. Therefore:

What are the values of $Z$ for $CO_2, CH_4$,and $O_2$ at $200 \ bar$ and $900 \ bar$ pressure?

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 $atm$? ($a = 4.17$,$b = 0.03711$)

Consider the following figure. Which of the following gases show negative as well as positive deviation from the ideal gas behaviour?

Explain: Why do real gases show deviation from ideal gas behavior?

Consider the van der Waals constants,$a$ and $b$,for the following gases:

Gas	$Ar$	$Ne$	$Kr$	$Xe$
$a / (atm \ dm^6 \ mol^{-2})$	$1.3$	$0.2$	$5.1$	$4.1$
$b / (10^{-2} \ dm^3 \ mol^{-1})$	$3.2$	$1.7$	$1.0$	$5.0$

Which gas is expected to have the highest critical temperature?