Objective: The objective of this experiment is to use acid-base extraction techniques to separate a mixture of organic compounds based on acidity and/or basicity. After the three compounds are separated we will recover them into their salt forms and then purify them by recrystallization and identify them by their melting points.
Procedure:
Extraction of Carboxylic Acid
A pre-weighed (0.315g) mixture of Carboxylic acid, a phenol, and neutral substance was placed into a reaction tube (tube 1). tert-Butyl methyl ether (2ml) was added to the tube and the solid mixture was dissolved. Next, 1 ml of saturated NaHCO3 solution was added to the tube and the contents were mixed separating the contents into three layers. Once this was completed…show more content… (note: the collection of crystals from tube 2 and 3 are done separately.) The crystals are then weighed to record the recovery of each substance. As in tube 4, ~0.1 g of the crystals are placed into a melting point tube and then the machine to record the melting point of the substances, as before with the collection of the crystals the melting point for tube 2 and 3 are recorded separately.
Results:
Neutral Substance:
For the neutral substance, 0.26g was recovered yielding a 26% recovery from the initial 0.315g sample. The melting point was recorded as 56-57℃.
Carboxylic Acid:
For the Carboxylic acid, 0.007g was recovered yielding a 7% recovery from the initial 0.315g sample. The melting point was recorded at 121-122℃.
Phenol:
For the phenol 0.018g was recovered yielding an 18% recovery from the initial sample of 0.315g sample. The melting point was recorded at 115-116℃.
Conclusion:
Neutral Substance:
Based on the melting point recorded for the neutral substance two possible candidates are 1,4-Dichlorobenzene (mp: 56℃) and 1,4 Dimethoxybenzene (mp: 57℃). Since, both of these candidates have a very similar melting point it can be hard to identify which one is our neutral substance. The recorded melting point was a range from 56-57℃ making the most likeliest identity of 1,4-Dimethoxybenzene.
Carboxylic Acid:
Based on the melting point recorded for carboxylic acid the two possible candidates are benzoic acid (mp:123℃) and
