Exploring Path Length ⦁ Generate a graph of height of liquid (cm) on the x-axis vs. optical rotation in degrees on the y-axis. You may do this on the Vernier or you may take your data and use Excel.

Part I Exploring Path Length
⦁ Generate a graph of height of liquid (cm) on the x-axis vs. optical rotation in degrees on the y-axis. You may do this on the Vernier or you may take your data and use Excel.
LabQuest App
⦁ Save your raw polarimetry data file on to LabQuest. Choose New from the File menu.
⦁ Tap the Data Table tab. You should see a data set with a column named “X” and a column named “Y.”
⦁ To rename the x column, tap the x-column heading. Enter Height as the Column Name and cm as the Units. Select OK.
⦁ In the same manner, rename the y-column. Enter Angle as the column name and deg as the units. Select OK.
⦁ Enter your data in the appropriate columns. Tap the Graph tab and confirm the graph is displaying Height on the x-axis and Angle on the y-axis.

2. Using the curve fit option in the Analysis menu, determine the relationship between liquid height and optical rotation.
3. Find the best-fit line through the data points. Determine the angle of rotation when the height of the sample is exactly 10.0 cm.
4. Calculate the specific rotation of sucrose using Biot’s law. Compare this value to the accepted literature value and calculate your percent difference.

Part II Exploring Concentration
5. Using the observed angle of rotation and Biot’s law, calculate the exact concentrations of each sample in g/mL. Record these values in Table II.

6. Generate a plot of the calculated concentration values in g/mL vs. optical rotation in degrees, as you did above. Again you may use the handheld or Excel to generate your graph. Don’t forget the 10% data point.

7. Based on your data, what is the relationship between optical rotation and concentration?

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