48672903-Chem-31-Experiment-No-1

The chloroform evaporated first so it was the one

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Unformatted text preview: . The chloroform evaporated first so it was the one that was collected as the distillate and the remaining liquid in the distilling flask contains the caffeine. The remaining liquid in the distilling flask was further heated until all the chloroform evaporated leaving caffeine crystals. An empty evaporating dish was weighed and it weighs 51.3522 g. After the caffeine crystals were isolated, the evaporating dish containing the crystals wasweighed again. It weighed 51.3826 g . By subtracting the weight of the crystals together with the evaporating dish and the evaporating dish we can get the weight of the caffeine that was extracted. Its weight is 0.0504 g. Thus the percentage yield of caffeine in the tea is1.42 %. The small amount of caffeine crystals that are obtained is attributed to some errors occurred during the experiment. In our first trial of liquid-liquid extraction, the solution that we extracted evaporated so in this experiment we only used the solution that we extracted from the 2nd trial that is why the amount of caffeine crystals that we extracted is half of the actual expected amount of the extracted caffeine. IV. CONCLUSION In order to isolate caffeine from tea, different types of extraction methods were done. T...
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