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Can you answer the laboratory ISOLATION OF

Procedure1. Put 5 g Na:CO, and 50 mL water in a beaker and heat to boiling.2. To this solution immerse 2 tea bags and allow an infusion for approximately 7minutes.3. Meanwhile prepare 25 mL of boiling water. Remove hot tea bags and immerse themthis time in 25 mL hot water, wait for 5 minutes. Remove the tea bags by squeezing asmuch as possible.4. Combine the two extracts and cool to room temperature. Extract the aqueous teasolution. 3 times with 20 mL chloroform. Do not shake the separatory funnelvigorously, in order to avoid a possible emulsion,5. Decant into an evaporating dish and evaporate chloroform in order to obtain crudecaffeine.SafetySodium carbonate is an irritant. It may be harmful if swallowed.Chloroform may cause irritation, nausea and vomiting and drowsiness uponshort term exposure.. Never try to taste the caffeine you separated!Be Careful with EmulsionsYou obtain an emulsion when one phase is dissolved in the other. If you get an emulsion youdo not have two layers but a kind of a fog of particles. Formation of an emulsion can be aproblem in extractions, because emulsions once formed can be quite stable and regaining ofthe two layers can be rather difficult. The best way to avoid this problem is not to let ithappen. Vigorous shaking may cause emulsions, therefore shake the separatory funnel gently.Sometimes you can get rid of an emulsion by swirling the funnel very gently in its uprightposition. If the emulsion persists you can add a small amount of saturated salt solution whichwill decrease the miscibility with the organic solvent and break the emulsion by salting-outeffect. Stirring the solutions slowly with a glass rod may also help. Finally if the aqueouslayer is not of any importance, separate as much of this layer as possible and place the organicphase plus the emulsion in an Erlenmeyer flask containing some drying agent covering thebottom of the flask. Swirl about 5-10 minutes and gravity filter the system using fluted filterpaper. Rinse the drying agent with the solvent and discard the drying agent. This way you

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