Materials Needed:
- Separatory Funnel
- 1 ring stand
- Steam Distillation Kit
- Thermometer
- Thermowell heater (heating well)
- 250 mL beaker (as receiver)
- Hot plate
- 100 mL beaker
- 50 mL beaker
- Spatula
- Some ice
- Boiling water bath
Procedure:
- Seperated excess molsh from caffeine dichloromethane solution with the use of the separatory funnel
- Then took solution and began a simple distillation to seperate the caffeine from the dichloromethane solution.
- After the dichloromethane was distilled, we took the received solution and poured successive amounts of the dichloromethane into the dried caffeine in the bottom of the round bottom flask.
- The small amount of dichloromethane and caffeine was poured into a 100 mL beaker(preweighed at 49.77g).
- The 100 mL with the caffeine solution was taken to a boiling water bath to evaporate the remaining dichloromethane.
- The remaining caffeine in the 100 mL beaker was then weighed(50.6 g)
- The 50 ml beaker was then placed on top of the 100 mL beaker with the caffeine to create sublimation.
- The 100 mL kit with the 50 mL beaker was placed on top of a heating plate.
- Ice was inserted in the 50 mL beaker.
- The sublimated caffeine stuck on the bottom of the 50 mL beaker was then placed scraped of and weighed. 0.140 g
Observations
- Simple distillation of the dichloromethane-caffeine solution began and proceeded rapidly. (approx. 10 min) Due to the low boiling point of dichloromethane. Distillation of the solution was done under an elephant trunk to absorb the fumes from the dichloromethane.
- After the distillation finished the caffeine was dried on the bottom of the round bottom flask.
- To remove the caffeine small portions of dichloromethane were placed into the round bottom flask.
- The dichloromethane in the solution was rapidly evaporated inside the boiling water bath. Evaporation was also done under the elephant trunk to absorb the fumes from the dichloromethane.
- The caffeine inside the 100 mL flask was weighed at 50.6 g. The total caffeine weighed 0.83 g. This also included some excess materials.
- When doing sublimation, the smoke began at approximately 220°C.
- After the sublimation, the total caffeine weighed 0.140g.
Percent Yield of caffeine in the 30 g of tea
.5%
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