Midterm 6B






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705121606
Posts: 68
Joined: Wed Sep 18, 2019 12:17 am

Midterm 6B

Postby 705121606 » Wed Feb 26, 2020 10:11 pm

It asks for which process with delta H and delta G be expected to be most similar? I narrowed it down to either a or b during the test but then I got confused on the difference between them. The only thing I noticed was that option a was all in the solid state whereas option b had many different phases. Can someone explain why option a was correct in this problem and why options b,c,d would be incorrect

Amanda Lin 2I
Posts: 101
Joined: Sat Aug 17, 2019 12:15 am

Re: Midterm 6B

Postby Amanda Lin 2I » Wed Feb 26, 2020 10:21 pm

ΔG° = ΔH° - TΔS°
ΔH° and ΔG° would be the most similar when ΔS° is closest to 0. Going from a solid to another solid would have the smallest change in entropy, so A is the correct answer.

Julie_Reyes1B
Posts: 105
Joined: Sat Jul 20, 2019 12:16 am

Re: Midterm 6B

Postby Julie_Reyes1B » Wed Feb 26, 2020 10:27 pm

This is the way I did it, but I'm not quite sure if it is correct. So I used the equation ΔG°= ΔH- TΔS°. So for G and H to be equal, TΔS°=0. B, C, and D would be wrong because there is a pretty clear change in entropy for each one.

Justin Seok 2A
Posts: 104
Joined: Sat Aug 24, 2019 12:15 am

Re: Midterm 6B

Postby Justin Seok 2A » Wed Feb 26, 2020 10:34 pm

Essentially, this problem is asking for which equation would cause the least entropy so that G and H are similar. Entropy changes quite significantly when phases change, so the equation with the least entropy change would be the one with the solids on both sides.


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