## S=0

$w=-P\Delta V$
and
$w=-\int_{V_{1}}^{V_{2}}PdV=-nRTln\frac{V_{2}}{V_{1}}$

Dina Geotas 4A
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Joined: Fri Sep 28, 2018 12:29 am

### S=0

When is entropy equal to 0?

Courtney Quan 1C
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### Re: S=0

An entropy of zero indicates there is no disorder. An example of this would be in a perfectly ordered material. If a system can only be prepared one way (W=1), using S=kbln(W), we have S=0, which indicates that the system could be a perfect crystal. This leads us to the third law of thermodynamics, which states that as temperature approaches absolute zero, entropy (S) also approaches zero.

Samantha Man 1L
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### Re: S=0

A system at equilibrium has no tendency to change in either the forward or reverse direction so it would have an entropy of 0.

Phan Tran 1K
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### Re: S=0

I think it's deltaS that can be zero. Not too sure if S itself can be zero, maybe at the hypothetical subzero?

Elizabeth Gallmeister 1A
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### Re: S=0

deltaS is also zero when the start conditions and end conditions of a process are the same, because entropy is a state function.

LaurenJuul_1B
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### Re: S=0

delta S is zero when there is no change in the disorder of the system between the initial and final values

S itself I think can be zero if you have a perfect system, but I'm not 100%

Jason Ye 2I
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### Re: S=0

Entropy is equal to zero in a perfect crystal at T= 0K

Olivia L 4E
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### Re: S=0

Jason Ye 2I wrote:Entropy is equal to zero in a perfect crystal at T= 0K

This is for residual entropy (3rd Law of Thermodynamics) but if you are asking for when delta S = 0, that's entirely different and occurs when the system is reversible and returns to its original state.

EllaBerry
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### Re: S=0

S is equal to zero in a perfect crystal when the temperature is 0K.

chrisavalos-2L
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### Re: S=0

S is equal to zero when there is temperature is at zero Kelvin and when there is no disorder, in the instance of a perfect crystal.

404982241
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### Re: S=0

entropy is a state function therefore if the initial entropy is equal to the final entropy then the delta s is 0

Ricardo Martin 1J
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### Re: S=0

S=0 in a perfect crystal (T= 0 Kelvin)

Jacqueline Duong 1H
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### Re: S=0

S is equal to zero when there is no change in the state of entropy and temperature reaches 0 K