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Chemistry 2720 Fall 1999 Quiz 4 Solution

The reaction has a certain entropy change tex2html_wrap_inline15 . The reaction is exothermic so it will heat the contents of the adiabatic container, resulting in an entropy increase tex2html_wrap_inline17 . Since the reaction is spontaneous, the second law requires that tex2html_wrap_inline19 , i.e.\ that tex2html_wrap_inline21 . Note that tex2html_wrap_inline26 so that we cannot determine the sign of tex2html_wrap_inline15 from this argument. It is tempting to conclude that tex2html_wrap_inline15 is positive (due to the gaseous product), but it is in fact negative. Roughly speaking, the ionic products organize the solution in a way which more than compensates for the increased disorder due to the hydrogen gas.



Marc Roussel
Fri Dec 10 14:02:00 MST 1999