Molar Entropy

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Jacquelyn Hill 1
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Molar Entropy

Postby Jacquelyn Hill 1 » Sun Mar 11, 2018 4:54 pm

Is the size of a molecule significant in determining whether it has a higher molar entropy than another molecule?

Alyssa Pelak 1J
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Re: Molar Entropy

Postby Alyssa Pelak 1J » Sun Mar 11, 2018 6:01 pm

Yes! A larger molecule has a higher molar entropy. This is because it is more complex and has more electrons.

ConnorThomas2E
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Re: Molar Entropy

Postby ConnorThomas2E » Sun Mar 11, 2018 6:41 pm

Things that often lead to higher molar entropy are more complex structures (the bonds can absorb more vibration energy), heavier atoms, and formation of gas particles. Therefore, size and complexity are helpful to determine the molar entropy.

Sophia Bozone 2G
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Re: Molar Entropy

Postby Sophia Bozone 2G » Sun Mar 11, 2018 7:14 pm

Yes, the larger a molecule is, the larger it's molar entropy. This is because a larger molecule has more possible substates, positions, or orientations. It's degeneracy is higher. For example, a linear molecule can have two possible orientations, whereas a trigonal planar molecule could have more.

Jacquelyn Hill 1
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Joined: Sat Jul 22, 2017 3:01 am

Re: Molar Entropy

Postby Jacquelyn Hill 1 » Sun Mar 11, 2018 8:34 pm

Also, is the size a more significant factor in determining this than the state that the molecule is in?

Mishta Stanislaus 1H
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Re: Molar Entropy

Postby Mishta Stanislaus 1H » Sun Mar 11, 2018 11:03 pm

Jacquelyn Hill 1 wrote:Also, is the size a more significant factor in determining this than the state that the molecule is in?


I have this same question.

AtreyiMitra2L
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Re: Molar Entropy

Postby AtreyiMitra2L » Sun Mar 11, 2018 11:12 pm

Generally, the heavier the substance, the higher the molar entropy. This occurs because the energy levels are closer together, which means there are more possible orientations the substance can acquire. Therefore, it will have a higher molar entropy.

604807557
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Joined: Wed Nov 16, 2016 3:02 am

Re: Molar Entropy

Postby 604807557 » Sun Mar 11, 2018 11:45 pm

Large = more complex = more possible orientations = higher entropy
Small = less complex = less possible orientations = lower entropy

Jacquelyn Hill 1
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Re: Molar Entropy

Postby Jacquelyn Hill 1 » Tue Mar 13, 2018 6:36 pm

Between a solid and liquid, which substance would have a higher molar entropy? Would a heavy solid have a higher or lower molar entropy than a lighter liquid or vice versa? Would a lighter solid have a higher or lower molar entropy than a heavy liquid?

Lorena Zhang 4E
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Joined: Fri Sep 28, 2018 12:16 am

Re: Molar Entropy

Postby Lorena Zhang 4E » Thu Feb 07, 2019 8:42 pm

The mass is definitely a determining factor. However, we usually consider degeneracy first then the mass of the molecule.


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