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Acid Base Extraction

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Acid Base Extraction
The purpose of this experiment is to separate a solution of an acidic and organic compound and purify its respective acidic product through the techniques of an acid base extraction, recrystallization, and use of Melt Temp (melting point range). The reaction of an unknown acid (3-chlorobenzoic acid) with diethyl and sodium hydroxide was observed, and the solution naturally separated into an aqueous and organic solution.

The mixture of acid and organic solution was created and then separated through the Hirsch funnel into separate beakers of an aqueous and organic solution. The neutral compound was obtained through evaporation, while the unknown acid was identified though the addition of hydrochloric acid. The melting point of both the neutral compound and unknown acid will be taken. The melting point of the organic solid will be compared with its literature value, and the identity of the unknown acid will be revealed through its melting point range.

In this experiment, in order to identify the purified acid, the melting point of the unknown product was to be compared with the three known products. The melting point range of the product was found to be 152.4 C – 155.0 C. Of the three melting point ranges of the known products, 3-chlorobenzoic acid matched up the best, as the theoretical melting point is 154.0 C – 157.0 C. Thus, the product obtained was 3-chlorobenzoic acid. Additionally, 0.238g of the 3-chlorobenzoic acid were obtained. Of the 0.238g of acid used in recrystallization, 0.228g were recovered, yielding a 95.8% recovery rate. As for the organic compound, 0.166g of fluorene was secured and its respective melting point range was 116.0 C – 117.0 C.

The identity of final acidic product was revealed through the comparison in melting points of the three known products. The melting point range matched up similarly with 3-chlorobenzoic acid.

The experiment began with 0.210g of the mixture of an unknown acid and fluorene. The yield in products

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