## Ideal gas

$\Delta U=q+w$

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### Ideal gas

How do 3/2*R and 5/2*R correspond to PV=nRT and when would they be applicable?

Vincent Tse 2B
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### Re: Ideal gas

The values you listed correspond to molar heat capacities and are typically used for solving heat in terms of moles (q = nC(v/p)deltaT).

The subscripts V and P stand for either constant volume or pressure: so, Cv reads as molar heat capacity at constant volume and Cp as molar heat capacity at constant pressure.

Cv = 3/2*R and Cp = 5/2*R

Also, Cv and Cp can also be used to calculate change in entropy under changes in temperature; using Cv or Cp depends on the context of the reaction/problem (refer to page 34 in the course reader).

Hopefully this helped!