Question

The van der Waals' constants for four gases $P, Q , R$ and $S$ are $4.17, 3.59, 6.71$ and $3.8$ atm $ L^{2} mol^{-2} $ Therefore, the ascending order of their liquification is

• A. $R < P < S < Q$
• B. $Q < S < R < P$
• C. $Q < S < P < R$
• D. $R < P < Q < S$

Answer 1

Answer: (C)

As the value of van der Waal's constant increases, ease of liquification of a gas also increases. The ascending order of van der Waal's constants for gases $P, Q, R, S$ is as
$\underset{(Q)}{3.59} < \underset{(S)}{3.8} < \underset{(P)}{4.17} < \underset{(R)}{6.71}$
Thus, the order of ease of liquification is $Q < S < P < R$