## 5/2R vs 3/2R

$\Delta S = \frac{q_{rev}}{T}$

Briana Yik 1H
Posts: 30
Joined: Fri Sep 28, 2018 12:20 am

### 5/2R vs 3/2R

how do we know when to use 5/2R versus 3/2R?

lizettelopez1F
Posts: 29
Joined: Fri Sep 28, 2018 12:19 am

### Re: 5/2R vs 3/2R

Cp=5/2r is used when you need to find the heat capacity of an ideal gas with a constant pressure. Cv=3/2R is used when you need to find the heat capacity of an ideal gas with a constant volume

KatrinaPho_2I
Posts: 60
Joined: Fri Sep 28, 2018 12:28 am

### Re: 5/2R vs 3/2R

These values only work if you are dealing with monoatomic ideal gases.

abbydouglas1K
Posts: 65
Joined: Fri Sep 28, 2018 12:26 am

### Re: 5/2R vs 3/2R

If the question says that the pressure is being kept constant(Cp) or that the volume is being kept constant (Cv) you will use 5/2R and 3/2R respectively if the molecule in question is a monatomic gas.

Christopher Anisi 2K
Posts: 30
Joined: Fri Sep 28, 2018 12:21 am

### Re: 5/2R vs 3/2R

For a monoatomic gas under a constant pressure the Cp value is equal to 5/2R however if it is under a constant volume the Cv value is equal to 3/2R.