Essay about Identifying a Constituent of Panacetin

1072 Words Oct 24th, 2011 5 Pages
Emily Davis
Partner: None
Chemistry 253- TA: Alma Wellensiek
Lab 3: Identifying a Constituent of “Panacetin”
9/15/2011

Purpose: The purpose of this experiment is to determine the unknown component of Panacetin.

Theory: Panacetin is an analgesic (pain reducing) and antipyretic (fever reducing) drug that is sold in drug stores. However, there is a suspicion that this bottle may be counterfeit, not containing the chemicals that it should. Panacetin should be made up of about 50 percent of the unknown component that we previously separated out of Panacetin for testing. We suspect that this unknown compound is either acetanilide or phenacetin, both of which can be toxic to humans. It is very important that this component is
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These were most likely impurities, in which case I added a bit more water than was necessary. Also, the lab manual says to take two samples of each mixture (unknown; ½ phenacetin; ½ acetanilide) for the melting point, but we only conducted one. There were a few safety concerns in this lab. Both phenacetin and acetanilide are known to be mild irritants, thus contact with skin and eyes should be avoided or minimized around the unknown. Another issue to keep in mind is that we will be moving glass from hot to cold surfaces, which can cause the glass to crack or break. Extra care should be taken when lowering the temperature of a beaker to avoid this issue.

Observations/ Results: When boiling the water before placing it in the unknown, my water never actually came to a boil. It was steaming very heavily and I was losing a considerable amount of water, especially from my smaller beaker, so I had to just assume that it was hot enough. This may have affected the amount of material that I got to dissolve. Either way, the fact that it took 51mL was a good indicator that my unknown was phenacetin, due to phenacetin having a much lower solubility than acetanilide. I also noticed that even though I had put in more hot water than phenacetin should have needed to dissolve (45.9mL), white flakes still remained in the beaker. I assumed these to be impurities. Observations/
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