Question

Given below are the critical temperatures of a few gases. When the gases are started cooling, which gas will liquefy first and which will liquefy in the end?

Gas	$T_C/K$
$N_2$	$126.0$
$C{O}_2$	$304.10$
$N{H}_3$	$405.5$
$O_2$	$154.3$

• A. $N_2$ will liquefy first and $N{H}_3$ at last
• B. $N{H}_3$ will liquefy first and $C{O}_2$ at last
• C. $N{H}_3$ will liquefy first and $N_2$ at last
• D. $C{O}_2$ will liquefy first and $N{H}_3$ at last

Answer 1

The correct option is C $N{H}_3$ will liquefy first and $N_2$ at last

Higher the critical temperature, faster is the liquefaction of the gas. Hence, $N{H}_3$ will liquefy first and $N_2$ at last.