AGaeta_2C
Posts: 112
Joined: Wed Sep 18, 2019 12:21 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 :)

Donna Nguyen 2L
Posts: 100
Joined: Sat Aug 24, 2019 12:17 am

### Re: Questions about Equation Sheet

I believe that Cp = (5/2) R applies to diatomic and polyatomic gases, while Cv = (3/2) R applies to monoatomic gases.

ALegala_2I
Posts: 102
Joined: Thu Jul 11, 2019 12:17 am

### Re: Questions about Equation Sheet

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.

[img]Screen%20Shot%202020-02-11%20at%2011.53.40%20AM[/img]
Attachments

Jack Riley 4f
Posts: 100
Joined: Sat Aug 24, 2019 12:17 am

### Re: Questions about Equation Sheet

Cp = 5/2R and Cv = 3/2R both apply to monoatomic gases. Cp is for constant pressure and Cv is for constant volume