CHEM 12A
NAME__________________________
FOOTHILL COLLEGE
DISTILLATION SUMMARY
1. Report the Density of your distillate in the table below:
DATA TABLE
Density (g/mL)
Density (g/mL)
% Ethanol by
Trial #1
Trial #2 (if
volume
applicable)
Simple
Fractional (F1)
2. To determine the % Ethanol by volume (column 3 above), use Table 3.1 in
your Mohrig Procedure text and find the six data points closest to your
density (2 above and 2 below your density).
Determine a least squares equation for the relationship between % Ethanol (y)
and density (x) using the data points. Since your two distillates have very
different densities, you will need to repeat the calculation twice.
[(y=mx +b) where y= %vol and x= density]
Simple
Fractional
Slope m
y-intercept b
Plug in your density as x and calculate your % Ethanol (y) then record it in
the Data Table above. Repeat for Fractional distillate.
3. Use a spreadsheet to plot your data points collected in lab: Temp(°C) (y)
versus vol distillate (mL) (x) for both simple and fractional distillations.
Plot them separately and attach copies of the plots to this summary sheet.
4. What is your yield of Ethanol from the simple distillation in
mL?____________________
%EtOH/100 (from Table above) • vol distillate (50 mL)
5. What is the theoretical yield of Ethanol from the
fermentation?____________________
(Note: Use the quantity of sucrose to compute the the quantity of Ethanol as your
theoretical yield here, rather than assuming 12% Ethanol by volume. Show your work
below.)
6. What is the % yield of Ethanol from your fermentation?____________________
Show your work
CHEM 12A
FOOTHILL COLLEGE
DISTILLATION SUMMARY
NAME__________________________
7. How many mL of azeotrope did you collect during your Fractional
Distillation?____________________
Estimate this from your Plot, from the # mL collected before the temperature rose
abruptly.
8. What volume of Ethanol was collected during your Fractional
Distillation?__________________
[Note: this is (volume of azeotrope) x %EtOH (v/v) in Fractional distillate]
show your work.
9. What is your % recovery of Ethanol from Fractional
Distillation?____________________
volume of EtOH in Fractional distillate/ vol EtOH in simple distillate
10. How successful was your Fractional Distillation? (Compare composition to
literature ethanol: water Azeotrope)
11. If you were to repeat this experiment, what, if anything, would you do
differently?