Answer:
In system A: A gas and a solid react to form a new solid product. the system entropy decreases.
In System B: Rubbing alcohol evaporates on the skin. liquid alcohol is converting to gas by evaporation so the system entropy increases.
Explanation:
Entropy is a thermodynamic quantity measure the degree of disorder of a certain system.
Gases have larger entropy compared to liquids which is larger than solids.
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(A) When a gas convert to a solid, its entropy decreases. ... because solids have less energy and entropy than solids.
So, in system A: A gas and a solid react to form a new solid product. the system entropy decreases.
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(B) Any chemical reaction that increases the number of gas molecules also increases entropy.
So, in System B: Rubbing alcohol evaporates on the skin. liquid alcohol is converting to gas by evaporation so the system entropy increases
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