Describe the temperature dependence of the heat capacity of a diatomic gas.© BrainMass Inc. brainmass.com June 3, 2020, 9:31 pm ad1c9bdddf
You should just draw the sketches qualitatively, don't do any complicated computations here.
At zero temperature the heat capacity is zero. All the degrees of freedom are "frozen", i.e. k T is smaller than the spacing of the energy levels. Then, if we raise the temperature, the heat capacity of the translational degrees of freedom rises to it's asymptotic value of 3/2 k. Depending on the volume this transition from zero to 3/2 k happens over the course of
10^(-10) K. So, this would be the first part of the sketch.
Next the rotational degrees of freedom start to kick in. This happens at a few tens of K, you can take e.g. 40 K. So, what you see is that the value of the heat capacity slowly starts to rise from 3/2 k to 5/2 k around 40 K ...
A detailed explanation is given. The expert examines temperature dependence of heat capacity of diatomic gas.