Q 8.17

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Affy_Hussain_3A
Posts: 9
Joined: Wed Sep 21, 2016 2:56 pm

Q 8.17

Postby Affy_Hussain_3A » Sun Jan 29, 2017 6:32 pm

Answer key says for diagram A, "work is done by the system" and for diagram B, "work is done on the system." Why isn't it "work done by the system" for both diagrams?
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Adam_Alyafaie_1L
Posts: 12
Joined: Wed Sep 21, 2016 2:58 pm

Re: Q 8.17

Postby Adam_Alyafaie_1L » Sun Jan 29, 2017 7:02 pm

Hey so your question is on part b right? Think of it through the formula w=-NRTlnV2/V1 where V2 is final volume and V1 is the initial volume. Since we are going from a gas to a liquid the volume will decrease, lets say it goes from 2 to 1. Then you will get ln1/2 which will give you a negative number and will overall give you a positive work. When work is positive that means work was done on the system. Hope this helps

Isaiah Sandoval 1D
Posts: 8
Joined: Wed Sep 21, 2016 2:58 pm

Re: Q 8.17

Postby Isaiah Sandoval 1D » Sun Jan 29, 2017 9:04 pm

To add on to Adam, the reason why you can use this equation is because this is reversible.


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