In this issue. - ACS Publications

media attention right now is solarenergy, and teachers find that experiments that ... perimentfor their environmental chemistry course in which they i...
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The Interaction of Light with Matter Light is a pervasive commodity in our daily life because it is a source of energy for driving chemical reactions. The interaction of light with matter manifests itself in many ways that are of interest to the chemist. Light can initiate reactions, he converted to other forms of energy and trapped within the products of a reaction, he converted to other forms of energy and emitted, or be produced and emitted from the reaction rather than absorbed and used by it. Three articles in this issue deal with some of these phenomena. Balzini, Bolletta, Ciano, and Maestri (page 447) discuss the involvement of light in electron transfer reactions, both as a reactant and as a nroduct: thev also emnhasize "the important role that can Ge played ir. .hese p r o c k m by suitable chemical species called sensitizers." One of the applications of the reaction of light with matter which is receiving a lot of media attention right now is solar energy, and teachers find that experiments that are related to this topic are received enthusiastically by students. Boudreau, Rauh, and Boud r e a u (page 498) have designed a solar cell laboratory experiment for their environmental chemistry course in'which they illustrate solid state semiconductor and electrochemical principles by having the students prepare and study a CdSe . . photoelectrochemi~alcell. An interesting chapter in the history of photochemistry is presented by Nada (page 451) who tells the story of how photochemical research in Egypt began when Schonherg fled there from Nazi Germany and took advantage of the abundant sunlight as a source of energy for initiating his reactions.

Teaching the "Basics" in Chemistry There was a time when teachine" the Basics in Chernistrv meant introducing the atomic theory, explaining the mole concept, illustrating the balancing of equations, and starting on the general concepts underlying kinetics, thermodynamics, and theoretical chemistry; that the student had already mastered the Basics of Learning, such as reading, writing and thinking, was treated as a given. The exnanding student populaGon and the decliningstandards in ;re-coliege preparation, however, have made this assumption risky, if not downright dangerous, for a teacher of introductory chemistry. The recent President's Commission Report on the crisis in education has drawn public attention to this problem, but it is obvious from the papers which are published in this issue that it is a problem which teachers have recognized for some time now and have been working to combat. Science is a human enterprise-its body of knowledge is built by literally millions of individual contributions of data and theorv and its rrowth is denendent UDon the continued communiiation of results from all those wbrking in the field. If a researcher is unable to communicate his or her results, those results are useless, no matter how brilliant. Written communication of an idea is the final (and seldom-mentioned) step in the scientific method; and many teachers have been guilty of asssuming their students had learned this skill before they came to college. However, the declining ability of stu-

446

Journal of Chemical Education

dents to produce intelligible reports coupled with statements from prospective employers that their new employees' numher one problem is a lack of communication skills has motivated teachers to make formal attempts to stress writing abiliiy in their chemistry classes. Since chemistry teachers, even those who are excellent writers themselves. are not trained in the techniques for teaching writing, their efforts have often been made jointly with colleagues in the English Department. One such successful collaboration is described by Bailey and Markowicz (oaee . 467) who concentrated on -euidine- the students' efforts to write better lahoratory reports for a course in instrumental analysis. They worked together to produce a revised syllabus which included writing and formating standards and iointlv eraded and rave feedback to the students for each ;eport. As the course progressed they noticed substantial improvement in the quality of the reports and the students' attitudes toward them. Burkett and DunMe (page 469) use their experience from teaching a course in technical writing to analyze the common deficiencies of undergraduate chemistry and engineering majors and relate the techniques that they use to overcome these difficulties. They conclude with some suggestions for how technical faculty members can address these problems themselves. Goodman and Bean (page 483) have incorporated their efforts to develon writine skills into an extended lahoratorv project in organic chemGtry which was also designed to d i velop the students' problem-solving and analytical skills. The project requires each student to carry out an independent investigation and then report the results in the form of a paper suitahle for publication in a professional journal. The authors and their students both feel the interaction of the two obiectives have made the participants not only better writersbnt better thinkers as well. Teaching future chemists to express their ideas clearly is an admirable goal; however, for the teacher of the general introductory c&rse, the goal often has to he to teach students how to think clearly enough to have an idea to express. Many students still work at the concrete onerational level and need to he taught problem%olvingskills defore they can handle the basic concepts of chemistry. Genyea (page 478) describes a preparatory course designed expressly for improving prohlem-solving ability for students who wish to take the regular two-semester sequence of introductory courses. He outlines a eeneral nrohlem-solvine aonroach which he teaches to his .. &dents and gives examples of how it is applied. Battino (naee 485) has dealt with the nrohlem of concrete o~erational students who cannot invisibn the abstract constructs of chemistry by designing oversize lecture demonstration models which work well in a large lecture hall. He gives instructions for constructing these models and explains how he uses them to allow his students to "see" how chemical reactions take place. Even concrete operations need to be done with skill, and Beasely and Heikkinen (page 488) have developed a technique, based on research in psychomotor learning, to improve laboratory technique in such areas as weighing, pipeting, and titrating. ~~~~~~

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