Critical temperature of a gas depends upon the magnitude of the intermolecular forces. Following are the critical temperatures of some gases-
H2 (33.2 K), CO2 (304.1 K), NH3 (405.5 K), O2 (154.3 K)
What would be the order of the tendency of liquefaction of gases1
H2 > O2 > CO2 > NH3
2
H2 > O2 > NH3 > CO2
3
NH3 > CO2 > O2 > H2
4
NH3 > CO2 > H2 > O2