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Question
Answer in brief.
What is entropy? Give its units.
Solution
- Entropy is a measure of molecular disorder or randomness.
- An entropy change of a system is equal to the amount of heat transferred (Qrev) to it in a reversible manner divided by the temperature (T) in Kelvin at which the transfer takes place. Thus,
`triangle "S" = ("Q"_"rev")/"T"` - Units of entropy: J K–1
Note: Entropy or its change ∆S is a state function and depends on the initial and final states of the system and not on the path connecting two states
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