midterm vs final question

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Kim
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midterm vs final question

Postby Kim » Sun Mar 19, 2017 12:48 pm

in the winter 2014 final exam, #2 part B is based on a container with two compartments separated by a divider. when the divider is lifted, there is considered a change in volume. But in this year's midterm, 2A has the same set up (two compartments divided by a wall) but opening the valve is not considered a change in volume, thus resulting in work=0 (something needed for the rest of the problem). Why is that? Don't these two contradict each other?

Chem_Mod
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Re: midterm vs final question

Postby Chem_Mod » Sun Mar 19, 2017 1:08 pm

In both questions the calculations are the same because they are very similar set-up.

In both questions the total volume of the system does not change.
In both questions the volume available to each gas increases. Hence both questions calculate the entropy the same way.

In 2014 final exam there was no work done, same for the midterm question.

Although the 2014 final exam has more questions and harder because it is a final exam.


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