Path Independence of Entropy Change

Thread starter sigmaro
Start date Jan 12, 2011
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Change Entropy Independence Path

AI Thread Summary

The discussion centers on proving the path independence of entropy change, with participants exploring various equations related to entropy (dS), heat transfer (dQ), and thermodynamic variables. Key equations presented include dS=dQ/T and its transformations, highlighting relationships between entropy, temperature, and volume changes. The conversation involves manipulating these equations to demonstrate that the change in entropy does not depend on the specific path taken in a thermodynamic process. Participants seek verification of their derivations to ensure accuracy in their understanding. The thread emphasizes the mathematical relationships that underpin the concept of entropy in thermodynamics.

Jan 12, 2011

sigmaro

Is there any way to prove that entropy change is independent from the path?

dS=dQ/T
dQ=dE+PdV
d(PV)=PdV+VdP
dS=nCd[ln(T)]+nR[ln(T)]-VdP/T
i go this far, but it is not very different from dS=nCd[ln(T)]+PdV/T

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Jan 12, 2011

sigmaro

i think i got it
dS=dQ/T
dS=(nCdT+PdV)/T
PV=nRT
dS=nCd[ln(T)]+nRTdV/TV
dS=nCd[ln(T)]+nRd[ln(V)]
can somebody check?

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