The molar heat capacity at constant volume of a colourless gas is found to be 25 J mol⁻¹ K⁻¹ at room… · ABC26PH0708
Subject: Physical Chemistry · Chapter: Gaseous State · Topic: Gaseous State – General · Exam: JAM 2001-2022 · Marks: 2 · Difficulty: Medium
The molar heat capacity at constant volume of a colourless gas is found to be $25 \mathrm{J} \mathrm{mol}^{-1} \mathrm{K}^{-1}$ at room temperature. The gas must be
(a)$\mathrm{N_2}$
(b)$\mathrm{O_2}$
(c)$\mathrm{CO_2}$
(d)$\mathrm{SO}_{2}$
Answer
Answer: D ✓ checked by 4AB · confidence high
Explanation
Cv = 25 J ≈ 3R: translation (3/2R) + rotation of a non-linear molecule (3/2R) — the colourless bent SO₂ (d); N₂, O₂ and linear CO₂ give 5/2R.