The number of statement's, which are correct with respect to the compression of carbon dioxide from point (a) in the Andrews isotherm from the following is ____.
A. Carbon dioxide remains as a gas upto point (b) B. Liquid carbon dioxide appears at point (c) C. Liquid and gaseous carbon dioxide coexist between points (b) and (c) D. As the volume decreases from (b) to (c), the amount of liquid decreases
Answer: 2
Solution
Compressing from point (a), the carbon dioxide stays entirely gaseous until liquefaction sets in at point (b), so the claim that it remains a gas up to that point is sound. Liquid first appears at (b), not at (c); by the time the system reaches (c) the gas is fully converted, so placing the first liquid there is wrong. Along the flat stretch between (b) and (c) liquid and vapour sit in equilibrium together, so that statement is sound. As the volume shrinks from (b) to (c) more vapour turns to liquid, so the amount of liquid grows rather than falls, and that statement is wrong. Two of the statements are correct.
JEE Main · 2023 · 24 Jan 2023 · Shift 2 · Integer answer
