THE CHEMISTRY LABORATORY: A LESSON IN
About 100 years ago, the Chairperson of the Chemistry Department at Johns
Hopkins University, and one of the pioneers of chemical education in America,
Ira Remsen, wrote the following: (uploaded to the web by Steve Murov, Modesto
Junior College).
While reading a textbook of chemistry, I came upon the statement "nitric acid acts upon copper." I was getting tired of reading such absurd stuff and I determined to see what this meant. Copper was more or less familiar to me, for copper cents were then in use. I had seen a bottle marked "nitric acid" on a table in the doctor's office where I was then "doing time!" I did not know its peculiarities, but I was getting on and likely to learn. The spirit of adventure was upon me. Having nitric acid and copper, I had only to learn what the words "act upon" meant. Then the statement, "nitric acid acts upon copper," would be something more than mere words.
All was still. In the interest of knowledge I was even willing to sacrifice one of the few copper cents then in my possession. I put one of them on the table; opened the bottle marked "nitric acid;" poured some of the liquid on the copper; and prepared to make an observation.
But what was this wonderful thing which I beheld? The cent was already changed, and it was no small change either. A greenish-blue liquid foamed and fumed over the cent and over the table. The air in the neighborhood of the performance became dark red. A great colored cloud arose. This was disagreeable and suffocating - how should I stop this? I tried to get rid of the objectionable mess by picking it up and throwing it out of the window, which I had meanwhile opened. I learned another fact -nitric acid not only acts upon copper but it acts upon fingers. The pain led to another unpremeditated experiment. I drew my fingers across my trousers and another fact was discovered. Nitric acid also acts upon trousers. Taking everything into consideration, that was the most impressive experiment, and, relatively, probably the most costly experiment I have ever performed. I tell of it even now with interest. It was a revelation to me. It resulted in a desire on my part to learn more about that remarkable kind of action. Plainly the only way to learn about it was to see its results, to experiment, to work in a laboratory.
The description above is very amusing and expresses an enthusiasm for chemistry that we all should strive for. Ira Remsen also recognized the vital importance of the laboratory experience in chemistry. However, he was very fortunate that this particular experiment did not have dire consequences. Experiments should never be conducted using the methods described. List all the violations of good safety practice in the experiment described by Ira Remsen and suggest some safer approaches to finding out what was meant by the words "acts upon". [Note: A question about the availability of hoods might emerge during a consideration of this exercise. Reference to some pictures of alchemists such as Weiditz (An Alchemist), van Ostade (The Alchemists), or Rink (Teniers' The Laboratory) might help provide an answer to this question. Copies of these pictures are available at the "Pictures of Alchemists' site (http://www.levity.com/alchemy/alchem-a.html) under the History of Chemistry (V-E) at the Chemistry Webercises Directory. Be sure to click on the desired picture to convert it into a full screen picture.]
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