Why are more Massive compounds or elements greater in molar entropy than those that have less mass?
Also, does this only apply to gas or does it apply to any state of matter?
Mass vs Entropy
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Re: Mass vs Entropy
Larger atoms tend to have higher entropies because of increased molecular motion and disorder. Following that note, entropy of a molecule will increase with increasing complexity. This is because in every molecule, there is a certain number of states (degeneracy), and the number of available states increases with molecular complexity. This applies to any molecule in any state. Entropy also changes across phases. A general rule in that delta S (gas) >delta S (liquid) >delta S (solid). This makes sense if you think of the ability for molecules to move in a gas versus solid.
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Re: Mass vs Entropy
Larger elements/compounds have greater entropy because all of the different positions it could be in (more disorder). To add on, a molecule with a linear orientation with different elements has greater entropy that a molecule in a pentagon or octagon shape because the linear one can bend and is less rigid so it has higher entropy.
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Re: Mass vs Entropy
To add on, more massive atoms have larger molar entropy because they have a greater number of fundamental particles (electrons, protons, etc.), so they have a greater number of possible states.
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Re: Mass vs Entropy
More mass means that molecule is more complicated and therefore has more options for possible states, which leads to greater entropy
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Re: Mass vs Entropy
Larger molecules have more overall configurations which allow for a higher entropy.
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Re: Mass vs Entropy
Atoms with larger mass tend to have more particles, which makes their entropies higher. Molecules with high mass will also tend to have more atoms, which means more positional entropy.
Re: Mass vs Entropy
In general, more complex molecules will have greater molar entropy because they are more complicated, meaning there are a greater number of microstates associated with the compound. This is true for all molecules, regardless of state.
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