Arrange the following gases in increasing order of van der Waals constant '$a$':
$A$. $Ar$; $B$. $CH_4$; $C$. $H_2O$; $D$. $C_6H_6$
Choose the correct option from the following:

For $1 \ mol$ of gas,the plot of $pV$ vs $p$ is shown below. $p$ is the pressure and $V$ is the volume of the gas. What is the value of compressibility factor at point $A$?

Which intermolecular force is most responsible for the liquefaction of inert gases?

Which among the following statements is/are incorrect regarding real gases?
$(i)$ Their compressibility factor is never equal to unity $(Z \neq 1)$.
$(ii)$ The deviations from ideal behavior are less at low pressures and high temperatures.
$(iii)$ Intermolecular forces among gas molecules are equal to zero.
$(iv)$ They obey Van der Waals equation,$PV = nRT$.

The given graph represents the variation of $Z$ (compressibility factor = $\frac{PV}{nRT}$) versus $P$,for three real gases $A, B$ and $C$. Identify the only incorrect statement.

Identify the correct variation of pressure $(p)$ and volume $(V)$ of a real gas $(A)$ and an ideal gas $(B)$ at constant temperature. ($y = p$; $x = V$)