## Entropy Changes Due to Change in Pressure

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

Mia Navarro 1D
Posts: 52
Joined: Fri Sep 29, 2017 7:04 am

### Entropy Changes Due to Change in Pressure

Why is the initial pressure the numerator of the ln segment of the equation, though volume and temperature changes entail the respective final value as their numerators?

Isita Tripathi 2E
Posts: 52
Joined: Sat Jul 22, 2017 3:00 am
Been upvoted: 1 time

### Re: Entropy Changes Due to Change in Pressure

ΔS = nR ln (V1/V2)
using boyle's law for ideal gases:
P1V1 = P2V2
P1/P2 = V2/V1
replacing this in the equation:
ΔS = nR ln (P1/P2)

Britney Alvey 1B
Posts: 31
Joined: Fri Jun 23, 2017 11:39 am

### Re: Entropy Changes Due to Change in Pressure

It is always good to remember that pressure is inversely proportional to volume.