## constant pressure and volume

Volume: $\Delta S = nR\ln \frac{V_{2}}{V_{1}}$
Temperature: $\Delta S = nC\ln \frac{T_{2}}{T_{1}}$

annikaying
Posts: 94
Joined: Sat Sep 14, 2019 12:16 am

### constant pressure and volume

How do constant pressures and volumes affect the calculations for entropy, enthalpy, and Gibbs free energy?

Kishan Shah 2G
Posts: 132
Joined: Thu Jul 11, 2019 12:15 am

### Re: constant pressure and volume

Constant volume means there is no work done. At constant pressures, q is equal to delta H and work is -PdeltaV.

cassidysong 1K
Posts: 100
Joined: Fri Aug 30, 2019 12:15 am

### Re: constant pressure and volume

^^ At constant pressure delta H equals q and at constant pressure work equals zero.

Kayli Choy 2F
Posts: 100
Joined: Sat Aug 24, 2019 12:17 am

### Re: constant pressure and volume

Additionally, if the problem says a reaction is isobaric, that implies that pressure is constant. If a reaction is isochoric, isovolumetric, or isometric, that implies that volume is constant.