The heat capacity of an ideal gas.

AI Thread Summary
For an ideal gas, the relationship ∂U/∂V=0 indicates that internal energy does not change with volume, leading to the conclusion that the heat capacity CV is independent of volume. The heat capacity is defined as CV=∂U/∂T at constant volume, emphasizing its dependence solely on temperature changes. The discussion highlights confusion regarding the application of Maxwell Relations and the derivation of heat capacity in relation to volume and temperature. It is clarified that since volume does not vary with temperature in this context, certain derivative relationships do not apply. Understanding these principles is essential for solving related thermodynamic problems effectively.
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The question states: For an ideal gas ∂U/∂V=0. Show that this implies the heat capacity _{}CV of an ideal gas is independent of volume.

I can't wrap my mind around how I could answer this question besides just stating the obvious. The expression for heat capacity is:
_{}CV=∂U/∂T (with v held constant)
The subscript V means that volume must be held constant and that heat capacity is only dependent only upon a changing temperature.

The chapter of my thermodynmaics book that this homework problem comes from is about Maxwell Relations, if that helps at all. However, all that helped me do was derive the fact that ∂U/∂V=0 but not actually answer the question.

Any help would be WONDERFUL! thanks so much! :)
 
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Can one use

CV=∂U/∂T = (∂U/∂V)(∂V/∂T)?
 
I guess I'm not sure how exactly that works, but that would just make the heat capacity 0, which wouldn't necessarily answer the question.
Plus, volume is not a function of temperature, so that rule would not apply here... I don't believe.
 
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