## Entropy and Work

LMendoza 2I
Posts: 41
Joined: Sat Jul 22, 2017 3:00 am

### Entropy and Work

What's the main relationship between entropy and work that is not done as heat?

Samantha Joseph 1F
Posts: 48
Joined: Fri Sep 29, 2017 7:04 am
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### Re: Entropy and Work

Since the relationship between entropy and work that IS done as heat is S = Q/T, and we know that Q = U - w, where U is the total internal energy and w is work that's not done as heat, then you can substitute that in and say S = (U-w)/T, showing the relationship between S and w.

Aijun Zhang 1D
Posts: 53
Joined: Tue Oct 10, 2017 7:13 am

### Re: Entropy and Work

$\Delta S = \frac{q_{reversible}}{T}$
When T (in Kelvin) is constant, then q = -w since U = q + v.
So $\Delta S = \frac{-w}{T}$ (T constant)

Also, any energy lost by doing work is compensated by heat going into the system.Then another equation about w is $W = -nRTln\frac{V_{2}}{V_{1}}$

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