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Landon Mutch
November 27, 2011
Chem 101 – B27
Lab 6: Caffeine in Cola Syrup
Abstract
Following the procedure outlined in the Lab Manual1, caffeine was extracted from cola syrup2
and the result for the class average weight by percent of the caffeine in the cola syrup was
found to be 0.89%.
Data and Results
Table 1. Class Data and Averages
Syrup Mass (g)
6.14 (mine)
6.17
6.15
6.170
5.54
7.07
6.01
6.15
6.22
Caffeine Mass (g)
0.1054 (mine)
0.0633
0.0578
0.0282
0.0349
0.0303
0.0973
0.0355
0.0358
Average Weight (%):
Weight (%)
1.72
1.03
0.940
0.457
0.630
0.429
1.62
0.577
0.576
0.89
Table 2. Density of Cola Syrup for my Experiment
Syrup Mass (g)
6.14
Syrup Volume (mL)
5.0
Syrup Density (g/mL)
1.2
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Discussion
In this experiment, caffeine (Fig. 1) was extracted from cola syrup by first diluting the syrup
with distilled water and dissolving sodium chloride3 and calcium hydroxide4 in the solution to
make the water heavier, then adding iso-propanol5 (Fig. 2) to bond with the caffeine and
remove it from the syrup solution, and finally adding ethanol6 to cause the caffeine to crystalize
out of the iso-propanol solution.
Figure 1.
Figure 2.
In the preparation of a standard cola product, one part cola syrup is usually added to five parts
carbonated water. So by knowing that the average amount of caffeine in the cola syrup is 0.89%
and that the syrup density is 1.2 g/mL, we can determine that there is an average of 0.76g of
caffeine in a typical 355 mL cola beverage (see calculations section). This may seem like quite a
bit of caffeine, but we must keep in mind that the process we used to extract the caffeine
results in a rather impure resulting product due to other substances in the cola being extracted
as well as caffeine. Also there may have been fibers of filter paper in the product from scraping
the crystals from the filter. If we wanted to obtain a much more pure extraction of caffeine
from the syrup, we would have to use a process such as sublimation which would very likely
result in a lower yield of caffeine than the one from this experiment.
Conclusion
Caffeine was extracted from cola syrup and the result for the average weight by percent of the
caffeine in the cola syrup was found to be 0.89%.
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References
1. Reimer, M., Chem 101 Lab Manual, pp. 6-1–6-5. (University of Victoria: Victoria, BC). Fall
2011.
2. Cola syrup. Pepsi Cola Canada Ltd.
3. sodium chloride. Lot: TI13CZEMS.
4. calcium hydroxide. FW 74.09.
5. iso-propanol.
6. ethanol. 100%