Question

At ordinary temperature, the molecules of an ideal gas have only translational and rotational kinetic energies. At high temperatures they may also have vibrational energy. As a result of this at higher temperatures (Cv= molar heat capacity at constant volume) :–

(a) Cv = 3R/2 for a monoatomic gas

(b) Cv > 3R/2 for a monoatomic gas

(c) Cv > 5R/2 for a diatomic gas

(d) Cv = 5R/2 for a diatomic gas

Answer 1

Correct option**(c) Cv > 5R/2 for a diatomic gas**

Explanation:

Monoatomic gas Cv = 3R/2

This value is same for high temperature also, In case of diatomic gas

Cv = 5R/2 (at low temperature)

Also,Cv > 5R/2 (at high temperature due to vibrational kinetic energy)