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<div class="moz-cite-prefix">On 11/02/2017 04:45 PM,<br>
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cite="mid:16a1b48b55e543b88193a5078f76850d@spiderman.MercerU.local">
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Good Afternoon,
<div>I am doing Ch 18 practice problems and I am lost on a
problem. I know that in order to predict the sign of entropy
change, you can look at which side of the reaction has more
moles of gas. What do you do when both sides have the same # of
gas moles?</div>
<div>For example:</div>
<div>PCl3 (l) + Cl2 (g) —> PCl5 (g)</div>
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<p>In this case the entropy would be greater in the products because
there are lots more places to put the energy. Think about the Cl2
molecule -- you basically have the one bond length and then the
rotation about the axes. In PCl5 you have give different bonds to
store energy plus the rotations about the axes.</p>
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<pre class="moz-signature" cols="72">--
Andrew J. Pounds, Ph.D. (<a class="moz-txt-link-abbreviated" href="mailto:pounds_aj@mercer.edu">pounds_aj@mercer.edu</a>)
Professor of Chemistry and Computer Science
Mercer University, Macon, GA 31207 (478) 301-5627
<a class="moz-txt-link-freetext" href="http://faculty.mercer.edu/pounds_aj">http://faculty.mercer.edu/pounds_aj</a>
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