Question

Define entropy. Derive the relation for Entropy change in a chemical reaction.

Answer 1

The second law of thermodynamics states that a closed system has entropy which may increase or otherwise remain constant. Chemical reactions cause changes in entropy and entropy plays an important role in determining in which direction a chemical reaction spontaneously proceeds.

Answer 2

In statistical mechanics, entropy is an extensive property of a thermodynamic system. ... In this viewpoint, thermodynamic properties are defined in terms of the statistics of the ... The fact that entropy is a function of state is one reason it is useful.

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