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Someone help with this organic chemistry lab. I have one question, but for some information this is what we did: Dissolve 5 g of Na

Someone help with this organic chemistry lab. I have one question, but for some information this is what we did: Dissolve 5 g of Na2CO3 in 250 mL of ion-exchanged water in a beaker.
10 tea bags are added
The solution is heated on a hot plate. When the solution boils, the hob is switched off, while
the beaker still stands on the plate.
Leave the mixture for 20 minutes. Stir gently with a glass rod occasionally, to increase
the extraction of caffeine. The tea bags should preferably not be punctured, as this will do so
more difficult to filter the mixture.
Filter the hot mixture through a piece of gauze in a glass funnel into a
Erlenmeyer flask, but leave the tea bags in the beaker. Use a spatula and then press
as much liquid as possible out of the tea bags.
Cool the flask with the solution in cold water to room temperature.
The mixture is extracted with 3 x 25 mL of dichloromethane. Shake gently during extraction
to avoid the formation of an emulsion. If an emulsion is formed, this will
making separation of the water phase and organic phase difficult. The combined organic phases
washed with 20 mL deionized water and dried with MgSO4.
The desiccant is filtered off, and the filtrate is collected in a tared 100 ml round flask.
Dichloromethane is evaporated on a rotavapor. Determine weight of extracted caffeine.
Take a small sample for melting point measurement and thin layer chromatography.
Purification of caffeine by sublimation
Scrape out as much of the caffeine as possible from the round flask and weigh it. Transfer this to that
outer tube on a "cold finger".
Mount the cold-finger and gas washing bottle as shown in fig. 2 and put on water suction and
cooling water. Be careful to install the hoses correctly to avoid backlash.
Heat the cold finger using a heating mantle (step 8) until all the caffeine has sublimed. Hit
off the heat and carefully loosen the hose to the water suction.
Scrape the caffeine from cold-finger onto a tared watch glass and weigh.
Measure the melting point of purified and unpurified caffeine. The question is can you draw schematically the procedure for isolating and purifying caffeine from tea, please show structures too. Will leave an upvote. 

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