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<font face="serif">I have had a couple of questions on how to use
Excel to make the graphs for the freezing point depression plots.
It's actually gotten easier to do this -- but it still will take a
little work.<br>
</font>
<ol>
<li><font face="serif">For one of your cooling curves enter the X
(time) and Y (temp) data in two columns.</font></li>
<li><font face="serif">Highlight the cells that represent the
"approach to freezing" where the slope is greatest. These
data will be used to draw the first line.</font></li>
<li><font face="serif">Once you have hightlighted them, click the
insert button at the top of the Excel window and look for the
scatter plot (the one with just data points and no lines).
Click this and you should see the first part of your plot.</font></li>
<li><font face="serif">In the plot itself click the right mouse
button. You should see an option to select data. Click on
this and then click "Add". This is going to allow you to add
another data series. You may have to mess with this some to
get it to work, but I was able to highlight the remaining X
data and then the Y data and add the new series to my plot. <br>
</font></li>
<li><font face="serif">Once you have both data series on the plot
you should be able to click on the individual data series on
the plot and add a trend line for each of them. Like I
mentioned in a prior e-mail, adjust the "forward" and "reverse"
forecast period so the two lines intersect.</font></li>
<li><font face="serif">Don'f forget to adjust your axes so your
plot fills the plot region. Also, I prefer full page graphs
to be turned in with the lab report -- not tiny graphs that
are the result of a "screen print".<br>
</font></li>
</ol>
<p><font face="serif">Hope that helps.<br>
<br>
</font></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
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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