## Entropy of gas vs liquid vs solid

$\Delta S = \frac{q_{rev}}{T}$

Nancy Le - 1F
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Joined: Fri Sep 29, 2017 7:07 am

### Entropy of gas vs liquid vs solid

Why is the entropy of a gas much greater than that of a liquid or solid?

Ava Harvey 2B
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Joined: Fri Sep 29, 2017 7:04 am

### Re: Entropy of gas vs liquid vs solid

The basic idea of why gases have a greater entropy than liquids or solids has to do with the spacing of particles. Gases have a higher entropy because they occupy a greater volume in comparison to liquids and solids. Gas molecules move freely at high speeds and are more spread out, thus they have more room and more positions in which they can be arranged. The more positions or microstates that can be occupied, the greater the entropy. Hope that helps!

Salma Quintanilla 1J
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### Re: Entropy of gas vs liquid vs solid

Liquids have more energy and entropy than solids. When there is an increased number of gas molecules, there is also an increase in entropy.

Ya Gao
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### Re: Entropy of gas vs liquid vs solid

When the molecules are in gas phase, there are many more possible states they can occupy compared to the possible states molecules can occupy when they are in liquid phase or solid phase. With more possible states, the entropy will be higher.

Brandon Fujii 1K
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### Re: Entropy of gas vs liquid vs solid

Whenever a substance is being heated AND is not going through a phase change, the temperature of the substance (average Kinetic Energy of each particle) increases. As the total kinetic energy of the particles of the substance increases, entropy increases. Therefore, because a gas has a higher temperature than that of a solid, the gas has a greater entropy.

Wayland Leung
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### Re: Entropy of gas vs liquid vs solid

What does it mean when there are more possible states a gas can occupy?

RussellChin_3A
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### Re: Entropy of gas vs liquid vs solid

By more "possible states" I think you mean more possible positions, as this determines the entropy of a substance. For a gas, it can occupy more possible positions, because like the person above said, gases can occupy a larger volume compared to liquids and solids. They are more able to freely move in a space, therefore can occupy more possible positions.

Justin Folk 3I
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### Re: Entropy of gas vs liquid vs solid

Because gas has more "randomness" by intuition. THere is inherently order in a liquid and solid-- they are all contained and there is only a set place that they can go. Gravity dictates this in a liquid and the lattice of a solid dictates this