Entropy of the System for irreversible expansions


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Amir Bayat
Posts: 115
Joined: Sat Sep 07, 2019 12:16 am

Entropy of the System for irreversible expansions

Postby Amir Bayat » Tue Feb 11, 2020 9:19 pm

What is the difference between the change in entropy for a reversible isothermal expansion vs an irreversible expansion? Are they exactly the same?

Cole Woulbroun 1J
Posts: 56
Joined: Thu Jul 25, 2019 12:16 am

Re: Entropy of the System for irreversible expansions

Postby Cole Woulbroun 1J » Tue Feb 11, 2020 10:00 pm

Yes, they are the same because entropy is a state function.

Cooper Baddley 1F
Posts: 100
Joined: Wed Sep 18, 2019 12:19 am

Re: Entropy of the System for irreversible expansions

Postby Cooper Baddley 1F » Tue Feb 11, 2020 10:04 pm

State functions means that the path doesn't matter so it is the same.

Amir Bayat
Posts: 115
Joined: Sat Sep 07, 2019 12:16 am

Re: Entropy of the System for irreversible expansions

Postby Amir Bayat » Wed Feb 12, 2020 3:29 pm

Also,

When is the change in internal energy zero for an irreversible expansion?

KaleenaJezycki_1I
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Re: Entropy of the System for irreversible expansions

Postby KaleenaJezycki_1I » Wed Feb 12, 2020 4:24 pm

Amir Bayat wrote:Also,

When is the change in internal energy zero for an irreversible expansion?


Internal energy is zero when Temperature is constant because there is no energy transfer if there is no change in temperature ( Internal energy measure the heat transfer) so there is none if temperature isn't changing. DeltaU= DeltaH-Deltan*R*T so if there is no temp change it all comes to be deltaU=0

Bryan Chen 1H
Posts: 58
Joined: Mon Jun 17, 2019 7:24 am

Re: Entropy of the System for irreversible expansions

Postby Bryan Chen 1H » Wed Feb 12, 2020 5:03 pm

i believe they are the same, or at least you assume its always reversible

205389184
Posts: 100
Joined: Sat Sep 07, 2019 12:18 am

Re: Entropy of the System for irreversible expansions

Postby 205389184 » Sun Feb 16, 2020 10:25 pm

Since entropy is a state function, that means the path you take does not matter, so they will technically be the same.

Rida Ismail 2E
Posts: 139
Joined: Sat Sep 07, 2019 12:16 am

Re: Entropy of the System for irreversible expansions

Postby Rida Ismail 2E » Sun Mar 01, 2020 12:06 pm

entropy is the same in both scenarios because entropy is a state function. It doesn't matter what path you take to get the change in entropy, it will be the same.


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