For which of the following ideal gas, is independent of temperature? — Thermodynamics and Thermochemistry Chemistry Question

💡 Solution & Explanation

Monoatomic gases like Helium (He) possess only translational degrees of freedom, which are fully active at all non-zero absolute temperatures, making their $C_{v,m}$ rigidly $3/2 R$. Diatomic and polyatomic molecules have vibrational modes that excite at higher temperatures, making their $C_{v,m}$ temperature-dependent.