Pressure Change

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

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Pressure Change

Why do we put the intiial pressure term above the final pressure term in the equation that solves for change in entropy? In other entropy equations, final volume and final temperature are in the numerator, while initial volume and initial temperature are in the denominator.

miznaakbar
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Re: Pressure Change

Since PV=nRT, P and V are inversely related. The entropy equation with pressure is derived from the volume equation, which is why the initial and final values flip places so that the initial pressure term is above the final pressure term.