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Question
In which of the following, entropy of the system decreases?
Options
Crystallization of liquid into solid.
Temperature of crystalline solid is increased from 0 K to 115 K
H2(g) → 2H(g)
2 NaHCO3(s) → Na2CO3(s) + CO2(g) + H2O(g)
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Solution
Crystallization of liquid into solid
Explanation:
- A system's disorder or difficulty is measured by its entropy.
- A liquid turns into a solid—a more ordered state—during the crystallisation process.
- Because the particles become more organised and have less mobility, entropy consequently falls.
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