2.3 Exercise 3

One might think that the internal energy of diatomic gases is given by $E_{\text{int}} = 5 R T / 2 .$ For diatomic gases near room temperature, what additional considerations would cause the internal energy to be less than that? What would cause the internal energy to be more than that? Hint: Their internal energy includes the total energy added in raising the temperature from the boiling point (very low) to room temperature.