An inexpensive alternative to steam - Journal of Chemical Education

An alternative to the smelly water that comes out of steam lines or for labs that do not have steam lines at all. Keywords (Subject):. Laboratory Equi...
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switch texts or switch t o a new edition, which means a major review of the study sheets to fit the new text. The review is no more complex than redoing lecture notes to fit anew text. If the material was well organized originally, the preparation of new study sheets for the new text goes rapidly. Obviously, if a topic included on a study sheet is not in the text or lab manual, then one must prepare a handout on the topic or be sure to explain i t in class. Actually the biggest chore in switching texts is checking the new problems to assign. Class Activities

Once students get over the initial shock of learning that the textbook is the text for the course and that thev do not have to copy everything down in class, the coursk moves quite smoothly. Student course evaluations a t the end of the year have always been favorable, and often enthusiastic. A typical comment is "don't change anything". The best part is that I really look forward to class. Students are alert and responsive. Time goes quickly. There is a electricity in the air as we do my favorite thing: organic rhemistrv. . ..--.-. a. Instead of talking about organic chemistry and giving students basic information, we go ahead and do organic. Let us look a t some examples. Instead of lecturing on nomenclature of unsaturated and cyclic compounds, I put the structure of beta-carotene on the board and have the class work out the systematic name. Initially they are stunned a t the size of the molecule, but then suggestions come bit by bit until the right name appears. There is a good feeling when the class realizes they can tame a monstrous molecule like that. Rather than lecturing extensively on elimination mechanisms, we do a few. For example, DDT-resistant insects have an enzvme that detoxifies DDT hv doine an elimination reaction. I put the structure of DDT on the board and have the class predict the product and then draw out the s t e ~of s the mechkism. Later in the course we synthesize com~oundson the board from simple starting materials. We make compounds such as cinnamonaldehyde, 2,4-D, benzedrine, aspirin, tvlenol, harhiturates, and a variety of familiar suhstakes.

Note that we bring into class many topics that catch the students interest but that also give us the opportunity to use the organic chemistry we are learning. Many new drugs or other com~oundsin the newspapers are mentioned in class and oftenmade the subject i f problem: how could i t be synthesized? or what would the NMR soectrum look like? Instead of lecturing on qual, I put a fist of qua1 tests and spectral properties on the board (or spectra on the screen) and have the class interpret each bit of information and then deduce the structure. For each kind of problem I first work a few while thinking out loud. I t is most important that students catch the organic chemistry way of thinking and approaching problems. I t is difficult to learn these skills from a text. I t is so much easier to learn bv observine a real oreanic chemist doine real nrohlems. A good tradiiional lec&er will also teach problem solving this wav, .. if he does not omit i t in the rush to cover the material. Actually, what we are trvina to do is save the eood noints of the traditional lecture system but eliminate the dr;dgery of covering material. I am sure that if Nisbet were here todav he would approve. Asample copy of astudy sheet may he obtained by writing the author.

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2. Khruaaeh. N. J. Chem. Edur. 1961,28.280. 3. Levine, a. J. C k m . Edue. 1962.29, 224. 4. Battino, R. J. Chsm. Edue. 1366.43,228. 5. Atkinaon, G.F. J. Ckm.Edur. 1970,47,561. 6. Lamben,F. L.J Chem. Educ. 1963,40.173. 7. Smith,R.B.J. Chsm.Edu. I967,44 14s. 8. Tmhanovsky, W . S. J. Chom.Edur. 198.45.536, 9. Harrison, E.A. In Dimrrary 01 Teaehiw I n n o u o t i o ~in Chemistry; Meeth, L. R: Gregory, D. S.,Eda.: Studies in Higher Education: Arlington, VA, 1981: p3.59. 10. Harrison, EA.; Harrison,A.M.J. Chem.Edue. 197.5,32,654. 11. Burmeister, J. L. In Directory of Teaching Innovoliom in Chomiafry; Mmh, L. R.: Gregory, D. S., Eds.: Studies in Higher Education: Arlington, VA, 1981:p237. ; of 12. Boaz. P. lo Soume Book lor Ckmlatry T e m k n ; Lippincott. W.T., ~ d .~ivisioa Chemical Education, American Chemical Soeiety: Washingtan, DC, 1981:p 119. 13. Shani, A.: Singerman, A.J Chsm.Edur. 1982,69,221. 14: Morrison, R. T. In Placeedinga 01 the Chicogo Conformce an Libem1 Eduotion. Number I. October 18-19. 1985: Rice, M. R.Ed: College Cenkr for Curricular Thought. Univeniity of Chicago: Chicago, 1986; p 50.

An Inexpensive Alternative to Steam Not all laboratories have steam lines. In some that do, the steam lines take a long time to clear the water that has condensed in them since their previous use. As a result, the steam and water are dirty and, often, foul smelling. We have found an inexpensive alternativeto steam and hot water baths. Four-cup (coffeeor tea) water heaters may he purchased for less than $7 each. They are one-piece,sturdy, flameless, have an insulated handle and cover, require minimal additional instruction in their proper use, and heat rapidly. They will easily accommodate a 250-mLround-bottom flask. These units can be used in conjunction with a Power Mite to control the rate of heating. Ben Ruekberg Kansas Newman College Wichita, KS 67213

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