2. Add 100 ml of deionized water and 2.0 g of anhydrous sodium carbonate. Place the beaker on a hotplate. Place a watch glass on top of the beaker. Gently boil the contents of the beaker for 10 minutes.
3. Decant the hot liquid into a 100 ml Erlenmeyer flask. Add 50 ml of deionized water to the tea beaker and again bring the contents to a boil for 10 mins. Again decant the liquid in the beaker into the 100 ml Erlenmeyer flask.
4. Cool the tea extract to room temperature.
5. Transfer the tea extract from the 50 ml Erlenmeyer flask to a 250 ml separatory funnel that is supported by a ring on a ring stand.
6. Add 10 milliliters of dichloromethane to the separatory funnel and extract Caffeine into dicloromethane for 2 times.
7. Dried the combined dicloromethane layer with Na2SO4.
8. Decant dichloromethane into 25 mL beaker.
9. Place the beaker in hot plate and slowly heat the beaker to evaporate dichloromethane until it remain 5 mL of dichloromethane.
10. Allow the beaker to cool and crystals of caffeine will form in the solution.
11. Set the aspirator pump apparatus and fil Caffeine using Buchner funnel.
12. Weight the dry Caffeine and calculate weight percent of Caffeine in Tea leaves.
3. Pre-Lab questions
1. What is Alkaloids.
2. Why we have to put Na2CO3 into hot water.
3. What is the function of Na2SO4.
4. The extract of Caffeine from Tea leaves using hot water is liquid-liquid or solid-liquid extraction, and extract of Caffeine using dichloromethane is liquid-liquid or solidliquid extraction.