Extraction Of Caffeine Lab Template (Page 6 of 8) in pdf

Extraction Of Caffeine Lab Template Page 6

Turn the hotplate on “high.” The water in the beaker will begin to boil and its heat will cause the

dichloromethane inside the flask to boil. At that point, you will soon see dichloromethane begin

to drip out of the condenser into the waste beaker.

7. As the dichloromethane becomes hot and vaporizes (boils), the dichloromethane vapor will

travel into the cool condenser where it will condense back to liquid and drip out of the bottom of

the condenser into the waste beaker. The caffeine should not vaporize and travel with the

dichloromethane. Rather, it should be left behind in the flask.

Once all the dichloromethane has boiled out of the flask and the flask is dry, turn off the heat and

disassemble the apparatus. There should be caffeine residue inside the flask.

Record the appearance of the caffeine on the report sheet. Wipe the outside of the flask

completely dry and weigh the flask containing the caffeine. Record the total mass on the report

sheet, and then calculate the mass of caffeine extracted by subtracting the mass of the empty

flask. Complete the lab report by calculating your percent recovery of caffeine.

8. Pour the distilled dichloromethane into the bottle labeled “recycled dichloromethane.” The

coffee in the sep funnel can be discarded down the drain. Wash the sep funnel with water, rinse

it with acetone from the bottles with red lids near the sink, and return the funnel. The caffeine

can be washed out of the flask using water (and acetone if necessary). Return the 125 mL flask

(do not put it in your drawer).

Extraction Of Caffeine Lab Template Page 6