Teaching organic chemistry - Journal of Chemical Education (ACS

Edward Hart. J. Chem. Educ. , 1925, 2 (2), p 110. DOI: 10.1021/ed002p110. Publication Date: February 1925. Cite this:J. Chem. Educ. 2, 2, 110-. Note: ...
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JOURNAL OP C ~ M I C EDUCATION AL

FSBRUARY, 1925

TEACHING ORGANIC CHEMISTRY EDWARD HART, LAFAmTTE COLLEGE, EASTON, PA. It is true, is it not, that the teacher who is unable to put himself in the position of the pupil is unfit to teach ? If this be true, and I think it is, I shudder to think how many teachers of other things beside chemistry are unfit. It follows from a very superficial consideration of teaching, I think, that the view point of the beginner is all important. Dr. James W. Moore once said to me: "When I studied chemistry the professor began somewhat as follows: 'We will begin by studying oxygen. This is a colorless, tasteless gas (and I did not know what a gas was). This gas is prepared by heating a mixture of potassium chlorate and manganese dioxide (and I had never heard of either) in a tubulated retort (and what is that?), collecting the gas in a bell jar (and what is that?) in a pneumatic trough (another unknown) over water. The retort is heated with a Bunsen burner as you see ( I saw but did not understand) supported on a tripod (Ha! I had studied Greek-that meant three feet).' Do you," he asked, "teach chemistry like that?" and I found, to my dismay, that I did teach it very much like that. Fortunately this happened very early in my career as a teacher. In the early days of organic chemistry teaching we proceeded by a method equally questionable. I was for a long time unable to see why students hated organic and seemed unable to assimilate it. After years of growing dissatisfaction with the result I concluded to undertake what I should have done long before, look a t the matter through the eye of the student. We began then with CHa spread out on the blackboard, like a flounder, with only two dimensions, length and breadth. Out of this we built up CaHe. Both of these concepts were an insoluble puzzle to the student. He lost interest a t once and the game was lost. I figured that I must give the boy something to do first, and arouse his curiosity. The destructive distillation of wood was something most boys had heard about. I told them more about it and we distilled wood in a simple cast-iron apparatus and collected all the products, gaseous and liquid and also examined the charcoal. We analyzed the gas in a simple f o m of Hempel apparatus and fractionally distilled the liquid after having first neutralized the acid with chalk or lime. The acetate of lime was then examined and, with some more acetate taken from a barrel, converted into acetic acid. Some acetate was heated and acetone prepared; from this we made chloroform and iodoform. The methyl alcohol was separated and methyl iodide prepared. This usually ended the half year's work, of two periods a week. By this time the boys were very much interested and extremely curious, for we had carefully avoided all explanations. All inquiries were answered by the statement that full explana-

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tions would be given next term. Next term we trotted out the flounder with. an entirely different result: the boys were eager to learn. The whole subject was pronounced hard but very interesting. Try this plan and see whether you like it. But map out the course carefully beforehand, see that the apparatus is simple and will work and let each student make his own apparatus, so far as is possible. And try out everything yourself first. If it fails in your hands be sure it will do so in his.