How to calculate W

Boltzmann Equation for Entropy:

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Brandon Mo 4K
Posts: 70
Joined: Fri Sep 28, 2018 12:15 am

How to calculate W

Postby Brandon Mo 4K » Thu Feb 14, 2019 10:59 pm

How are we supposed to calculate W (degeneracy)?

Hovik Mike Mkryan 2I
Posts: 95
Joined: Fri Sep 28, 2018 12:25 am

Re: How to calculate W

Postby Hovik Mike Mkryan 2I » Thu Feb 14, 2019 11:07 pm

Hello, to calculate degeneracy one has to know how many molecules are present and how many orientations it can form. The # of orientations can be denoted x and the number of molecules can be denoted n. Therefore x^n will give you the degeneracy. Hope this helped!

Ethan Yi 1K
Posts: 62
Joined: Fri Sep 28, 2018 12:28 am

Re: How to calculate W

Postby Ethan Yi 1K » Fri Feb 15, 2019 2:24 am

W = (# of equal energy conformations)^(# of molecules)

Faith Fredlund 1H
Posts: 68
Joined: Fri Sep 28, 2018 12:18 am

Re: How to calculate W

Postby Faith Fredlund 1H » Fri Feb 15, 2019 10:43 am

Generally when you are supposed to find the degeneracy of a system you are ultimately trying to find the entropy of a system.

S= (Kb)ln(W)
entropy= (Boltzman's constant)ln(degeneracy)

Systems with higher degeneracy have higher entropy because the atoms or molecules can possess more disorder in the way the are arranged in the system.

LaurenJuul_1B
Posts: 65
Joined: Fri Sep 28, 2018 12:17 am

Re: How to calculate W

Postby LaurenJuul_1B » Fri Feb 15, 2019 1:43 pm

W=(# of micro states)^(# of molecules)

or using s=kb(ln(W))

Ashe Chen 2C
Posts: 31
Joined: Mon Jan 07, 2019 8:23 am

Re: How to calculate W

Postby Ashe Chen 2C » Sat Feb 16, 2019 9:57 pm

W is calculated by
and then is plugged into the equation
to find the statistical/residual entropy

Aili Ye 4L
Posts: 58
Joined: Fri Sep 28, 2018 12:16 am

Re: How to calculate W

Postby Aili Ye 4L » Sat Feb 16, 2019 10:16 pm

W (degeneracy) is calculated by the number of microstates/equal energy conformantions to the power of the number of molecules. S (entropy) is thus equal to the Boltzmann's constant multiplied by lnW.

Yvonne Du
Posts: 64
Joined: Fri Sep 28, 2018 12:23 am

Re: How to calculate W

Postby Yvonne Du » Sat Feb 16, 2019 11:31 pm

(Numbers of possible ways)^numbers of molecules.

Danny Zhang 4L
Posts: 62
Joined: Fri Sep 28, 2018 12:26 am

Re: How to calculate W

Postby Danny Zhang 4L » Sun Feb 17, 2019 1:07 am

(# of mircostates)^(# of molecules)

Rehan Chinoy 1K
Posts: 67
Joined: Fri Sep 28, 2018 12:25 am

Re: How to calculate W

Postby Rehan Chinoy 1K » Sat Mar 16, 2019 4:34 pm

(number of orientations) ^ (number of molecules). Side note: I've seen some problems where one has to use Avogadro's number to find the number of molecules.


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