AP Chemistry / Unit 9: Thermodynamics and Electrochemistry

9.1 Introduction to Entropy

3 practice questions

Notes

Entropy ($S$) measures how dispersed matter and energy are.

$S$: gas > liquid > solid.
More gas moles, higher temperature, dissolving and mixing all increase entropy.

Practice

Which has the highest entropy?

$2H_2O(l)\to2H_2(g)+O_2(g)$. $\Delta S$ is:

Freezing water has $\Delta S$:

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