1. Why was the solution heated and then cooled during the recrystallization of the crude acetaminophen?
Recrystallization is a very important method of purification for organic solids. This process is carried out by the separation of compounds based on the difference in solubility. The steps to recrystallization can be described by the following
• Choose an appropriate solvent based on the compound’s characteristics
• Dissolve the compound in the minimum amount of solvent
• Slowly cool the solution to form the crystals
• Collect and wash the crystals utilizing a filtration set up
• Dry the crystals through vacuum filtration and natural evaporation in the laboratory drawer
The heating and cooling of the crude acetaminophen …show more content…
First, the contaminants during the transition steps of the experiment appear in the final product. These contaminants in starting materials could appear and cause the melting point of the product to have a larger range. Second, during purification measures, such as recrystallization and filtration, these steps may not go to competition leaving behind some of the undesired experiment materials. Third, there are several side reactions that occur between the p-aminophenol and acetic anhydride. These side reactions produce substances other than the desired product. When this occurs, there is less desired product …show more content…
The reagents, p-aminophenol and acetic anhydride, were synthesized into acetaminophen by utilizing a hot plate and catalytic acid. Additional measures were taken throughout the synthesis in order to ensure the purity of the acetaminophen. These measures included using suction filtration and recrystallization which also reinforced previous laboratory experience. After one week of drying in the laboratory drawer, the acetaminophen was assessed for purity through calculating the percent yield, gathering the melting point range and determining major peaks from the IR spectrum. The overall percent yield was 32.5% which was below the desired 100% yield. The percent yield was less than one hundred percent because the reaction did not go to completion, and some of the product may have been lost during transition steps. For future experiments, it would be interesting to synthesize the compound that is made by Ibuprofen. This is a drug that has similar medical uses as a fever and pain reducer. Additionally, it would be interesting to compare the synthesized acetaminophen and the synthesized Ibuprofen under the IR spectrum and determine the different functional groups associated with the two