Practice Midterm

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Practice Midterm

Postby Jesse_torres2H » Sat Mar 17, 2018 4:30 pm

From the practice midterm question 6a reads we can expect an endothermic reaction to be favorable at a very hight temp. Why would this be false?

Diane Bui 2J
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Re: Practice Midterm

Postby Diane Bui 2J » Sat Mar 17, 2018 4:37 pm

It is false because we do not know the value of delta S.
Endothermic means that delta H is positive. According to the gibbs free energy equation (delta G = delta H - TdeltaS), an endothermic reaction would be favorable at a high temp if delta S was positive as well. If delta S was negative and delta H was positive, then the reaction would never be favorable.

Justin Bui 2L
Posts: 51
Joined: Fri Sep 29, 2017 7:06 am

Re: Practice Midterm

Postby Justin Bui 2L » Sat Mar 17, 2018 6:21 pm

Yeah, I agree with what Diane said but I feel like it being completely false is a little unfair of a generalization. I think a lot of the time delta S happens to be positive so it is true that an endothermic reaction is favorable at high temperatures but it is true that negative entropy would throw that all off.

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