JEE Main · 2022 · 27 Jul 2022 · Shift 2 · Heat & Thermodynamics

Statement A is incorrect: a molecule with $n$ degrees of freedom has $n$ ways of storing energy, not $n^2$. Statement B is correct: by equipartition theorem, each degree of freedom contributes $\frac{1}{2}RT$ per mole. Statement C is incorrect: monoatomic molecules have 0 rotational degrees of freedom, diatomic molecules have 2. Statement D is correct: ${\mathrm{CH}}_4$ (tetrahedral) has 3 translational + 3 rotational = 6 degrees of freedom. Thus B and D are correct.