Test 2: Melting Ice


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Faith Fredlund 1H
Posts: 68
Joined: Fri Sep 28, 2018 12:18 am

Test 2: Melting Ice

Postby Faith Fredlund 1H » Fri Mar 08, 2019 5:05 pm

On test two its states:

Circle the one that best decsribes the change in Gibbs Free Energy (ΔG) for the process described below:
a) The melting of snow caused by a sunny day
ΔG<0 ΔG=0 ΔG>0

I put ΔG>0, but that is not the answer and I was wondering why. I thought melting was an endothermic process and doesn't that indicate a non-spontaneous process and a +ΔG?

Carine Tamamian 2B
Posts: 61
Joined: Fri Sep 28, 2018 12:23 am

Re: Test 2: Melting Ice

Postby Carine Tamamian 2B » Fri Mar 08, 2019 7:18 pm

I was confused about this as well. Sun is melting the ice, so it the ice has to be absorbing heat?
someone help, thanks

Ricky Ma DIS 4E
Posts: 72
Joined: Fri Sep 28, 2018 12:27 am

Re: Test 2: Melting Ice

Postby Ricky Ma DIS 4E » Fri Mar 08, 2019 9:46 pm

Ice melts by itself which requires no direct input of energy. A piece of ice outside would melt by itself thus spontaneous.

Chloe Likwong 2K
Posts: 70
Joined: Fri Sep 28, 2018 12:23 am

Re: Test 2: Melting Ice

Postby Chloe Likwong 2K » Sun Mar 10, 2019 12:58 pm

Melting of ice is a spontaneous reaction, it releases heat. Therefore, it has a negative deltaG.
You can also think about it another way. Liquid water has more entropy than solid ice. Thus, it can imply that deltaG is more (-).

Katie Sy 1L
Posts: 57
Joined: Fri Sep 28, 2018 12:18 am

Re: Test 2: Melting Ice

Postby Katie Sy 1L » Sun Mar 10, 2019 1:33 pm

it's a spontaneous reaction because ice will melt by itself, not needing any external heat to be added to the system, which is why deltaG is negative

Ashley P 4I
Posts: 64
Joined: Wed Nov 15, 2017 3:04 am

Re: Test 2: Melting Ice

Postby Ashley P 4I » Fri Mar 15, 2019 9:38 am

Is this the case with the sublimation of dry ice as well?

Nghi Nguyen 2L
Posts: 61
Joined: Fri Sep 28, 2018 12:18 am

Re: Test 2: Melting Ice

Postby Nghi Nguyen 2L » Fri Mar 15, 2019 9:39 pm

i just thought of it like when you put ice in room temperature, it starts melting without you having to heat it, so therefore it's spontaneous


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