Charles’ Law Lab

Using Graphical Analysis

 

1.  Find Graphical Analysis on the desktop and open it.

2.  Double Click on the “x” in the x-column of data.  This is in the upper left hand corner of your screen.  VERY UPPER LEFT CORNER IF YOU PLEASE!

3.  Name it “Temperature”

4.  Go down to the UNITS and put in “oC”.  (Hint:  If you use INSERT SYMBOL, you will find a “o”

5.  Click OK

 

6.  Now click on “y” and title it “Volume” with units of “mL”.

 

7.  Enter your numerical values for T2 in “x” and V2corrected in “y”.  Then enter your numerical values for T1 in “x” and V1experiment in “y”.

 

8.  Go up to ANALYZE and choose LINEAR FIT.  A line should appear through your two points which tells you the slope.

 

9.  Go up to ANALYZE and choose ZOOM GRAPH OUT.  You want to keep zooming out until your see the LINEAR FIT line cross the X-axis.  (A cute trick is to click on the magnifying glass with the negative sign in it on the tool bar along the top.)

 

10. Once you find the X-Axis intercept, go up to ANALYZE and choose INTERPOLATE.  Now, run your mouse arrow over the x-axis intercept area and record what value that is.  This should be the temperature at which the volume drops to zero.

 

11.  Now go up to DATA and choose NEW DATA SET.  A new column of x and y will appear to the right of your original column of data.  Click on these “x”s and “y”s and label them as you did before.  Put in your data for your second trial here. 

 

12.  Move your mouse arrow over to the word “volume” on the graph.  Double click on it.  Now you will need to select DATA SET 2 and check the box for Volume.  What you should see now is two lines on your graph.  If you can’t see both of them, try ANALYZE and AUTO SCALE GRAPH. 

 

13.  Go to ANALYZE and LINEAR FIT for the second set of data.  Where does it hit the x-axis?  (HINT:  If a box comes up and asks you which lines you want to linear fit, you just click on all of them and then it will linear fit each one).

 

14.  Now do this again with your 3rd set of data.

 

15.  When you are all done, call over Mr. Young for inspection.