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Posted: Tue Feb 11, 2020 12:45 am
On the constant and equation sheet, I saw the equations Cp= (5/2) R, Cv= (3/2) R, and U= (3/2)nRT, and it brought up some questions.
I know the equation to calculate heat capacity under a constant pressure is Cp= (5/2) R, but for which kinds of molecules does this apply to? monoatomic or diatomic? I also have the same question for the equation Cv= (3/2) R.
And what would the equation U= (3/2)nRT apply to?

Thank you :)

### Re: Questions about Equation Sheet

Posted: Tue Feb 11, 2020 1:00 am
I believe that Cp = (5/2) R applies to diatomic and polyatomic gases, while Cv = (3/2) R applies to monoatomic gases.

### Re: Questions about Equation Sheet

Posted: Tue Feb 11, 2020 11:54 am
Actually, both of the c values are for monoatomic gases. Cv is used when the reaction is carried out at a constant volume and Cp is used at constant pressure.

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### Re: Questions about Equation Sheet

Posted: Tue Feb 11, 2020 1:14 pm
Cp = 5/2R and Cv = 3/2R both apply to monoatomic gases. Cp is for constant pressure and Cv is for constant volume