Same chapter3 marksDifficulty: Medium
State the relation between Gibbs energy, enthalpy and entropy, and the condition for a spontaneous process.
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3 marksDifficulty: Medium
What is entropy, and how does it change when a solid melts and when a gas is compressed?
Original Khojo Papers practice question — not from a past board paper.
Answer
Entropy is a measure of the disorder or randomness of a system. Melting increases the disorder of the particles, so the entropy increases. Compressing a gas confines the molecules to a smaller volume and reduces the number of arrangements available, so the entropy decreases.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The second law says the entropy of an isolated system never decreases.
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