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Recrystallization Lab Report

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Recrystallization Lab Report
The objective of this experiment was to learn the process of recrystallization and how this process removes the impurities from a pure solid compound. The methods used to achieve this objective were also hot vacuum filtration in order to remove suspended solid impurities, and isolating the pure acetanilide. In the next lab, percent recovered was obtained through weighing the acetanilide sample as well as comparing its melting point range.
In this experiment, the sample, acetanilide was weighted to be 1.523 grams. The sample appeared to be a pale mixture of brown flakes before it was crushed into small flakes. When boiling the sample with 25 mL of water over the 75 mL of water steam bath, the sample started to change to dark drown flakes in some areas. When the water began to evaporate in the flask contain the impure acetanilide, 10 mL of water was added to keep it boiling. A hot vacuum filtration was conducted and after all the impurities were removed, the flask was set to cool down to room temperature before being placed into an ice bath to be recrystallized. During the filtration, changes in the sample occurred. The sample of brown flakes changed into snow-white crystals. Another vacuum filtration had to take place to obtain the crystals. When conducting the vacuum filtration, the small filter paper had to be weighed before hand for later purposes. The weight of the small filter paper was 0.098 grams. After the crystals were obtained in the small filter paper, it was folded up in a bigger filter paper to
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A few errors that could have been made during the experiment was not clearing out the flask, too much solvent could have been used, or even not enough time was allowed to recrystallize. The overall experiment was successful because the right measurements were taken in order to compare to the actual properties of the pure

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