Cv vs Cp

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CHEM 14B Lover
Posts: 33
Joined: Fri Sep 28, 2018 12:19 am

Cv vs Cp

Postby CHEM 14B Lover » Tue Feb 05, 2019 9:15 pm

To clarify, Cp is larger than Cv because Cp = heat supplied to heat the system + work down to expand the gas above. Is this correct? Does this also mean Cv=Cp if the system proceeds in a vacuum?

Shally Li 2C
Posts: 30
Joined: Fri Sep 28, 2018 12:22 am

Re: Cv vs Cp

Postby Shally Li 2C » Tue Feb 05, 2019 9:25 pm

The heat capacity at constant pressure (Cp) is greater than Cv because when heat is added at constant pressure, the gas is allowed to expand and some of the heat is used as work. At constant volume, the gas cannot expand so no work is done and all the heat goes into raising the temperature of the system.

Ian Marquez 2K
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Re: Cv vs Cp

Postby Ian Marquez 2K » Tue Feb 05, 2019 9:33 pm

Like said before, when there is a constant volume, energy cannot be released through work. Therefore, the heat capacity at constant pressure is higher because this added energy through heat can be given off through work and expansion.

Letizia Ye 4F
Posts: 62
Joined: Fri Sep 28, 2018 12:28 am

Re: Cv vs Cp

Postby Letizia Ye 4F » Thu Feb 07, 2019 1:25 pm

If volume is constant, there can be no work done from expansion, thus the heat provided to the system is converted to work, which explains the lower Cv value.


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