Isolation Of Caffeine From Tea (Chemistry)

Isolation of Caffeine from Tea CHEM243A 2-23-11 Abstract: The intend of this try was to isolate caffein from a tea bag. Once isolated, the caffein was purified exploitation sublimation. The percent recovery was calculated to be 83.3%. The run orientate of the original substance was 51ºC-139ºC. Since it was inaccurate, the melting school principal of some other groups sample was recorded. It was located to be 219ºC-227ºC. Results: part recovery=100*( lean of pure/weight of impure) Weight of gravelly Caffeine| Weight of Purified Caffeine| portion Recovery| 0.018 g| 0.015 g| 83.33%| | Started Melting| Completely resolve| Our essay| 51| 139| Other Groups Sample| 219| 227| Since the melting buck determined was so different from the cognise melting point of caffeine, there essential have been impurities in the sample. This is also wherefore some of sample melted presently while the stick took such(prenominal) longer. This wide melting mountain range also indicated impurities. reciprocation: The procedure used to isolate the caffeine from a tea bag is very particular. The first hound is to submerge the tea bag in hot water, much like when do tea to imbibe. This separates the soluble fraction from the water-insoluble cellulose, non-hydrolyzable, and tannins.

This step is moderately different from brewing tea because hardly 10 mL of water is used. All of the water without delay absorbs into the bag and must be squeezed out. Brewing tea to drink requires much more water. The next step in closing off is to add dichloromethane. The purpose of this step is to separat e the aqueous bed from the original socio-! economic class. This absorbs unloosen of the K-salts of gallic acid and glucose. The organic layer still contained caffeine and chlorophyll and any other organic compounds. The final step is to purify the caffeine from any impurities. Sublimation is the technique used. First, the vacuum is applied. whence ice water is placed in the inner tube. Last, the come alive is turned on below the device. The mixture of...If you want to get a full essay, ordinance it on our website: BestEssayCheap.com

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