Question

Specific heat of diatomic molecule at high temperature

Answer 1

At high temperatures, the specific heat at constant volume CvCv has three degrees of freedom from rotation, two from translation, and two from vibration.

That means Cv=72RCv=72R by the Equipartition Theorem.

However, I recall the Mayer formula, which states Cp=Cv+RCp=Cv+R.

The ratio of specific heats for a diatomic molecule is usually γ=Cp/Cv=7/5γ=Cp/Cv=7/5.