Isolation of Caffeine
weight of tea bags:
weight of crude caffeine:
weight of recrystallized caffeine:
% recovery of purified caffeine:
% caffeine in tea bags (by weight):
observed mp of recrystallized caffeine:
literature mp of caffeine:
Sketch TLC results.
Report Rf values either in a Table or on the sketch.
- What is a natural product? What is an alkaloid? What is caffeine? Be
sure to include the structure of caffeine.
- Discuss the theory of the isolation experiment. What properties allow
you to separate the caffeine from the other compounds present in tea leaves?
- How much caffeine is in tea based on the results of your experiment?
How accurate do you think your results are? At what points in the experiment
might you have "lost" some of the caffeine?
- What did you learn from mp and TLC analyses? Did your recrystallization
step provide you with purer caffeine?