Thursday, July 2, 2009

Fun with Aspirin

Today was just another fun at the lab. For our experiment, the class was given the meticulous task of making aspirin. Before the lab begun, our mentors gave us as brief of an explanation to the theory of the lab, although it did take a while -- more normal than usual. The material was hard stuff; sure, I understood the basic concepts that they taught, but the rest of the lecture on organic chemistry blew my mind. 

Thus, the lab begun. Aspirin is acetylsalicylic acid, a combination of acetic anhydride and salicylic acid. The lab required multiple steps. First, salicylic had to carefully be measured out of a protectively covered weigher while water was boiled at a constant temperature of 80-90 degrees Celsius. Once the water reached the perfect temperature, the salicylic acide would be mixed with other very acidic acids only to be heated over the hot water and after placed into an ice bath. Here, white crystals began to form from the reaction, and were then later scraped, mixed with water, and dried. Then, the crystallization process begun. The formed crystals were placed in boiling ethanol, where the crystals began to melt and return to a liquid state. The process where the solution was placed into an ice bath and sucked was then repeated. 

Once all the drying was finished, the finished aspirin crystals were placed in an oven for a final drying, weighed in a scale, and packed in a vile. Upon returning from lunch, our groups had to find the molar mass of the lab experiment if it went perfect, meaning that there were no mistakes such as dropping a few amounts of the aspirin crystals. Of course, this is impossible, so we calculated and compared the molar masses of both the experiment conducted without any flaws and our own. It turns out that we had a 98% yield -- what a success!

1 comment:

Don Gosney said...


Isn't it great to know that if all of the Walgreen's were to burn down a once you could make a killing by manufacturing your own aspirin? Just having fun with you.

I remember the first time I made aspirin (10th grade chemistry) by the time we finished there was a great demand for the finished product (no sense wasting it).

My recollections are that our end product wasn't quite as pure. Then again, we were still in a high school lab.

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