Burdge/Overby, Chemistry: Atoms First, 2e Ch14 | Page 5
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CHAPTE R 14? Entropy and Free Energy
14.3 ? Entropy Changes in a System
Calculating ????Ssys
The change in entropy of a system is the difference between the entropy of the final state and the
entropy of the initial state.
?Ssys = Sfinal ? Sinitial
Equation 14.3
Using Equation 14.1, we can write an expression for the entropy of each state,
Student Annotation: ?Remember that
the difference between two logs is equal to
the log of the corresponding quotient:
A
ln A ? ln B = ln ??__???
B
and that ln Ax = x ln A [: Appendix 1].
Wfinal
?Ssys = k ln Wfinal ? k ln Winitial = k ln _____?
??
???
Winitial
Combining this result with Equation 14.2 gives
(? )
(? )
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???
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