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<font face="serif">The solution to quiz 9 is now posted on the class
website.<br>
<br>
While most of you did significantly better than the last quiz,
there were a few things that concerned me.<br>
<br>
1. In the first problem you were adding a weak acid and its
conjugate base together to make a buffer. There was therefore,
unlike the last quiz, no need to subtract from the amount of weak
acid placed in the solution. In the last quiz we added a STRONG
base that consumed some of the weak acid and made the conjugate
base -- that was not the case in the present quiz.<br>
<br>
2. If you have excess acid or base in your system then you are
outside of the buffer region and Henderson-Hasselbalch equation is
not applicable.<br>
<br>
<br>
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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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