Test 2 Q 7  [ENDORSED]






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Katherine Grillo 1B
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Joined: Fri Sep 28, 2018 12:28 am

Test 2 Q 7

Postby Katherine Grillo 1B » Fri Mar 15, 2019 9:32 pm

Why is the change in Gibbs free energy negative when ice melts? Isn't it gaining heat or in other words, isn't delta H positive?

annabel 2A
Posts: 67
Joined: Fri Sep 28, 2018 12:18 am

Re: Test 2 Q 7  [ENDORSED]

Postby annabel 2A » Fri Mar 15, 2019 10:12 pm

Although deltaH is positive, deltaS is also positive (water is less orderly than ice), and deltaS*T is probably a greater value than deltaH which makes deltaG=deltaH-TdeltaS negative

taywebb
Posts: 60
Joined: Fri Sep 28, 2018 12:15 am

Re: Test 2 Q 7

Postby taywebb » Sat Mar 16, 2019 1:23 pm

Because the outside environment is providing that heat directly, making this a naturally occurring reaction, no extra energy must be put in to make this reaction occur, so it is spontaneous.

Rehan Chinoy 1K
Posts: 67
Joined: Fri Sep 28, 2018 12:25 am

Re: Test 2 Q 7

Postby Rehan Chinoy 1K » Sat Mar 16, 2019 4:39 pm

Just think about it conceptually -- the melting of ice is spontaneous in most temperatures, so deltaG should be negative.

Selina Bellin 2B
Posts: 62
Joined: Fri Sep 28, 2018 12:25 am

Re: Test 2 Q 7

Postby Selina Bellin 2B » Sat Mar 16, 2019 6:00 pm

the situation is spontaneous bc there's nothing else that needs to be done to the ice in order to melt it

Jonathan Christie 1I
Posts: 32
Joined: Mon Apr 09, 2018 1:38 pm

Re: Test 2 Q 7

Postby Jonathan Christie 1I » Sat Mar 16, 2019 7:37 pm

I was wondering how to come to this conclusion, thank you


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