Match the following gases with the shape of their Z versus P curve at 273 K. Gases: (P) H2, (Q) CO2. Curves: (1) Z rises continuously above 1 from the start; (2) Z falls deeply below 1 before rising. The correct matching is

JEE Main levelSingle correct optionDifficulty 2 of 3rg117

Match the following gases with the shape of their $Z$ versus $P$ curve at $273 K$ . Gases: (P) $H X_{2}$ , (Q) $CO X_{2}$ . Curves: (1) $Z$ rises continuously above 1 from the start; (2) $Z$ falls deeply below 1 before rising. The correct matching is

Hydrogen at

273 K

is above its Boyle temperature (

110 K

), so only the excluded volume effect is seen and

Z

rises from 1.

CO X_{2}

has a large

a

and is well below its Boyle temperature (

715 K

), so

Z

dips strongly before rising.