The Third Law

Boltzmann Equation for Entropy:

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Hector Acosta Discussion 1H
Posts: 51
Joined: Fri Sep 29, 2017 7:04 am

The Third Law

Postby Hector Acosta Discussion 1H » Fri Feb 02, 2018 3:15 pm

Can someone explain to me the third law of thermodynamics?

Cam Bear 2F
Posts: 60
Joined: Thu Jul 27, 2017 3:01 am

Re: The Third Law

Postby Cam Bear 2F » Fri Feb 02, 2018 3:55 pm

The third law of thermodynamics states that entropy of a perfect crystal is zero when the temperature is zero Kelvin. If it isn't a perfect crystal or if it is at a different temperature there will be residual entropy.

Cam Bear 2F
Posts: 60
Joined: Thu Jul 27, 2017 3:01 am

Re: The Third Law

Postby Cam Bear 2F » Fri Feb 02, 2018 3:58 pm

A perfect crystal only has one microstate so w=1. When you plug 1 into the equation S=kb*ln(w) and solve, you get zero.

Miguel Velasco 2J
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Joined: Fri Sep 29, 2017 7:07 am
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Re: The Third Law

Postby Miguel Velasco 2J » Sun Feb 04, 2018 11:44 pm

we know the micro state is w=1 because there exists no movement at 0 Kelvin therefore resulting in entropy equal to 0.


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