Irreversible Expansion


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Hannah Lee 2F
Posts: 117
Joined: Thu Jul 11, 2019 12:15 am

Irreversible Expansion

Postby Hannah Lee 2F » Sat Feb 08, 2020 8:10 pm

How would you calculate the entropy of an irreversible expansion of an ideal gas at constant temperature? Could that occur at changing temperatures?

005324438
Posts: 51
Joined: Sat Aug 24, 2019 12:16 am

Re: Irreversible Expansion

Postby 005324438 » Sat Feb 08, 2020 9:02 pm

If the temperature is constant, we have to use the equation S=nKln(V2/V1), reversible or irreversible. A reversible change can happen without a constant temperature, but if the pressure is constant, we have to use different equations depending on what is constant.

Caroline Zepecki
Posts: 101
Joined: Fri Aug 09, 2019 12:16 am

Re: Irreversible Expansion

Postby Caroline Zepecki » Sun Feb 09, 2020 7:49 pm

If the temperature is constant, but you have changing pressure instead, you would use S = nKln(p1/p2), so same equation but replace V2 with P1 and vice versa because they're inversely proportional.


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