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<p>Here is some assistance for the lab. It would be helpful if you
calculated the molarity of NaOH for each of your "good" trials
from lab today.</p>
<p>The molar mass of KHP is 204.22 g/mol, so to calculate the
molarity of the NaOH</p>
<p><img alt="$\mathrm{\frac{\frac{(mass\ of\ KHP)}{204.22}}{(volume\
of\ NaOH)}}$" style="vertical-align: middle;"
src="cid:part1.59DB2D9B.3E76B2B1@mercer.edu"></p>
<p><br>
</p>
<p>where all of your volumes are in liters and your masses in grams.</p>
<p><br>
</p>
<p>Now, once you have calculated the molarities (to four significant
figures), select the THREE molarities from todays lab that have
the best precision. Circle these in your lab notebook and on your
report form. Compute the average molarity for your NaOH using
the THREE molarities that have the best precision.</p>
<p>For example, if in lab I had the following results...</p>
<p>0.1301</p>
<p>0.1289</p>
<p>0.1296</p>
<p>0.1240</p>
<p>0.1304</p>
<p>I would use 0.1296, 0.1301, and 0.1304 (Average Deviation:
0.0003) and come up with an average of 0.1300.</p>
<p>Let me know if you have questions about this.<br>
</p>
<p> <br>
</p>
<p><br>
</p>
<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
Director of the Computational Science Program
Mercer University, Macon, GA 31207 (478) 301-5627
</pre>
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