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I guess some of you have started your reports for exp 15 since<br>
I've received questions about it.<br>
<br>
I have a help file. You will find it by going to the following
link,<br>
<br>
<a
href="http://www.chemistry.ohio-state.edu/%7Erzellmer/chem1220/faq/faq_1220.htm">
<b>Helpful Tidbits for 1220</b></a><br>
<br>
and then clicking on the link for exp 15,<br>
<br>
<a
href="http://chemistry.osu.edu/%7Erzellmer/chem1220/faq/exp15.txt"><b>Exp
15 - Help for Exp 15</b></a><br>
<br>
I also have an example of the data tables and graphs for exp 15,<br>
<br>
<a
href="http://chemistry.osu.edu/%7Erzellmer/chem1220/lab/exp15.pdf"><b>Exp
15 - Example of Data Tables and Graphs Using MS Excel</b></a><br>
<br>
These are simply examples. It doesn't show how to do them.
Please<br>
note a couple of things:<br>
<br>
1) Parts A and B are both in H2O as solvent and are graphed
as<br>
<b>ONE </b>set of data. Make them <b>one set of
data </b>in Excel. There<br>
should be a smooth curve fit. It shouldn't be a
straight line in<br>
this case (although it can be for certain substances).
<br>
<br>
Part C is a separate set of data and should be a
separate line. Again,<br>
use a non-linear best-fit line.<br>
<br>
2) Do <b>NOT </b>draw the lines by hand. There is NO need
to. If you have<br>
decent data <b>Excel </b>should be able to do a
pretty good job at putting<br>
a smooth curve "through" your points. You should NOT
have a wavy<br>
line. You should use a "scatter" graph with no lines
and then fit the<br>
points with a trend line. Use a non-linear best-fit
line. Look at the<br>
curves I used for the fits.<br>
<br>
3) If you have a point which seems to be out of place you
should include<br>
it on the graph but not the trend line fit. You do
this by plotting all the<br>
"good" points as one set of data and the "bad" point
as a separate data<br>
set. Then you can have Excel draw the trend line for
the "good" points.<br>
<br>
4) Note what is plotted on the x and y axes on graph 2 and
the direction<br>
of curvature for the 2nd graph in my example. You
should have that<br>
same curvature. If you don't (it looks more like
graph 1) you've likely<br>
graphed mole fraction on the y-axis vs. temp. on the
x-axis (reversed<br>
from what you should have).<br>
<br>
Also, someone asked about the "Points to Consider" on page 25.
These <br>
are there to help you with some of the things you should discuss in
the<br>
Results/Discussion section. I've also got some things in the "Exp
15 Help File"<br>
about this section.<br>
<br>
Dr. Zellmer
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