Given below are two statement : one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : SO₂(g) is absorbed to a large extent than H₂(g) on activated charcoal.
Reason R : SO₂(g) has a higher critical temperature than H₂(g).
In the light of the above statements, choose the most appropriate answer from the options given below.

Solution

Chemistry ma’am · 4 steps

Higher critical temperature means easier liquefaction, and easily liquefied gases stick more to charcoal.

1. Check the Assertion. Activated charcoal holds far more SO₂ than H₂. The question says "absorbed", but it means adsorbed: the gas collects on the charcoal surface. So A is correct.
2. Check the Reason. The critical temperature of SO₂ is about 430 K. That of H₂ is only about 33 K. So R is correct.
3. Link them. Physical adsorption works through van der Waals forces, the same forces that turn a gas into a liquid. A high critical temperature means strong intermolecular forces and easy liquefaction. Such a gas is therefore adsorbed more readily.
4. So. Both statements are true, and the higher critical temperature of SO₂ is exactly why it is adsorbed more. The answer is (b).

The idea to keep. For physisorption, a higher critical temperature means easier liquefaction and more adsorption. So SO₂, NH₃ and HCl beat H₂, N₂ and O₂.

Answer from the NTA final answer key. Solution by PrepWiser.