How Does Pressure Affect Heat Capacity in Identical Systems?

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Heat capacity at constant volume is lower than at constant pressure because energy is used for work during expansion at constant pressure. In identical systems heated under constant pressure, the system at higher pressure cannot be compared directly to one at lower pressure without altering other variables like temperature or volume. Thermodynamically, it is impossible to maintain identical conditions while varying pressure without adding more molecules or changing temperature. Therefore, the question of which system has a higher heat capacity under these conditions is fundamentally flawed. Understanding these principles is crucial for accurate thermodynamic analysis.
dripdrop
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I understand that the heat capacity of something run at constant volume is lower than at constant pressure, as at constant pressure the substance can expand, so some of the energy put into the system is used for work.

If i have two identical systems and heat them under constant pressure conditions, one system at higher pressure than the other. which will have the higher heat capacity and why?

cheers.
 
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dripdrop said:
If i have two identical systems and heat them under constant pressure conditions, one system at higher pressure than the other. which will have the higher heat capacity and why?

cheers.

This condition is impossible thermodynamically. To do this, you need to add more molecules or increase temperature, or decrease volume.
 

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