I'm just checking that it's okay to use Cv all the time as a heat capacity of an ideal gas, even when the volume's not constant. This is because the average energy per molecule is 3/2*Kb*T from kinetic theory, therefore the average energy per mole is equal to 3RT/2 = CvT etc.(adsbygoogle = window.adsbygoogle || []).push({});

I'm currently doing a calculation for a heat engine and I'm working out the change in internal energy at a constant volume and I need to make sure that we use Cv and not Cp as the heat capacity.

Also, what is the significance of Cp if it's not used? Is it just so that we can set gamma=Cp/Cv?

Thanks

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# Homework Help: Heat capacity of an ideal gas

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