Molar Entropies

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Coco Hailey 2E
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Joined: Fri Sep 25, 2015 3:00 am

Molar Entropies

Postby Coco Hailey 2E » Wed Feb 15, 2017 4:18 pm

When deciding which has the higher molar entropy, I understand that it depends on molar mass and residual energy. Which trumps which?
In other words if one compound had a greater mass but less residual energy and the other compound a lower mass and more residual energy which molecule would have the higher molar entropy? Which matters more - the number of positions of the compound or the mass?

MelanieAu1G
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Re: Molar Entropies

Postby MelanieAu1G » Wed Feb 15, 2017 4:22 pm

It depends primarily on the conditions that they are asking you about the entropy under. If they are asking you about entropy at 0 K, there is no thermal entropy to consider, therefore only residual entropy needs to be accounted for (this is based off of the number of positions/ arrangements for a molecule and then the mass, mass is last priority). If it is asking about entropy at 25 C, or any other non-zero temperature (non-zero as in K), then you would have to consider thermal entropy and then residual entropy.

Coco Hailey 2E
Posts: 32
Joined: Fri Sep 25, 2015 3:00 am

Re: Molar Entropies

Postby Coco Hailey 2E » Wed Feb 15, 2017 4:24 pm

thanks so much! But what do you mean by thermal energy?

jeree pucan
Posts: 20
Joined: Wed Nov 18, 2015 3:00 am

Re: Molar Entropies

Postby jeree pucan » Thu Feb 16, 2017 4:35 pm

thermal energy as in heat q

404757006
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Joined: Wed Sep 21, 2016 3:00 pm

Re: Molar Entropies

Postby 404757006 » Fri Feb 17, 2017 2:52 pm

So when does molar mass come in as a factor of more/less entropy?


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