Question

The value of vander Waal's constant $a$ for the gases $O_2,N_2,{NH}_3,{CH}_4$ are $1.36,1.39,4.17$ and $2.253$ $P$ $atm$, $m^{-2}$ respectively. The gas which can most easily be liquefied is_____________.

• A. $O_2$
• B. $N_2$
• C. ${NH}_3$
• D. ${CH}_4$

Answer 1

The correct option is C ${NH}_3$

Van der Waals constant for the attraction (a) and volume (b) are characteristic for a given gas.

Some salient features of $a$ and $b$ are:

The gas having higher value of 'a' can be liquefied easily and therefore, hydrogen and helium are not liquefied easily.

So here, $N{H}_3$ will be liquefied easily.

Hence, the correct option is $\text{C}$