W. W. Wendlandt, R. A. Geanangel, ond D. Barry
A Tape-Slide Freshman Chemistry Course for Non-Science Majors
University of Houston Texas 77004
A cassette tape-35mm slide teaching format was applied to a non-science major freshman chemistry course. T h e tape/slides, which were used to replace two of the three live class lectures per week, were also available to the students for audio-tutorial use outside of the classroom. We wish to describe the contents of this course and its application to the first year chemistry course. Course Content
The tapelslide format was applied to a non-science major, three-credit hour, two-semester, introductory chemistry course, Chemistry 135-136. This course was developed for non-science majors (usually liberal arts or business school majors) to partially satisfy the science requirement for their degree programs. Its primary purpose is to educate the student in the fundamentals of chemistry and its application to everyday life. It is not a rigorous course in subject matter content hut rather, an attempt is made to introduce an appreciation of chemistry and its impact on society. The first semester consists mainly of Titles of Taoe-Slide Lectures Ledvre No 1
2
7
42 43
44 45 46
47
4s
49
110
Title The Metric System Matter and Energy: Heat, Temperame. and Density Matter; ~ t o i i Mass c kale Chemical Combination Chemical Formula Writing Chemical Equations Atomic Structure Electronic Structure of the Atom Wave Functions: Orbitals The Chemical Bond: Ionic Bonding The Chemical Bond: Covalent Bonding Nueles* Chemistry I Nvdear Chemistry I1 The Gas Laws 1 The Gas Laws I 1 The Solid s t a t e The Periodic Table oxyeen and Oxidation I OX;& and Oxidation I 1 Chemistry of Hydrogen I Chemistry of Hydrogen I 1 Solutions I Solutions I1 Chemical Equilibria Acids and Bases The Halogens Interhalogene and Noble Gas Compounds T h e Metals I The Metals I 1 Electrochemistry I Electrochemistry I 1 Asymmetry in Nature I Asymmetry in Nature I 1 Organic Chemistry I Orxanic Chemistry I 1 Organic Chemist~yI11 Ozganic Chemistry 1V %me ~ e a d i o n of s Ozganie Compounds Polymers Fats and Carbohydrates carbohydratesand Biaehemioal Energetics ~ m i n o i c i d sand Proteins ~ ~ ~ lAcids e i and c the Genetic Code The Chemistry of Food Household Chemistry ~ i Pollvtion r Water Pollution The Chemistry of Medicine Metal Complexes
/ Journal of Chemical Education
fundamental principles of chemistry while applications are stressed during the second semester. The basic routine consisted of the following: Two tape/ slide lectures per week are given to the entire class as a group; the third period is devoted to discussion and prohlem solving by the instructor. Each tapelslide lecture is 30-40 min in length and usually contains from 20-30 slides. The work load for preparing the lectures was rotated so that the students heard three different instructors, each for a one-week period. Each of the instructors taught a section of the course and was responsible for the operation of the audio-visual equipment during the lecture and also conducted the discussion and problem solving period. In this manner, the students could identify with a given instructor and relate, to some extent, his voice and personality with the taped lecture. Some 49 lectures were prepared in this format, the contents of which are given in the table. About 25 of these are given during the first semester and the remainder in the second semester. To accompany the lectures, a hook1 containing copies of all of the slides was available to the students so that they could concentrate their attention on the taped audio part rather than note taking on the slide contents. The hook contained exercises and problems for each of the lectures and these were frequently used as the basis for discussion durina the weekly discussion periods. It also permitted an audi&utorial approach to the course since the students could check out a copy of the tape along with a small tape recorder. A small seminar classm m was available to the students as a listening area. If a student missed one of the lectures due to illness, or simply wanted to review the lecture, this approach was used. Since a laboratory was not given, short (-5 min) tape/ slide lecture demonstrations were prepared. These illustrated numerous experimental and synthetic approaches to chemistry and through the use of close-up photography, enabled each of the students to observe them in detail. Slide and Tape Details
Because a large quantity of slides was required (-1000), lack of funds dictated the use of Kodak Kodalith Ortho Film 6556, Type 3, for the slides. This is a negative type, high resolution film that is satisfactory for line drawings and typewritten copy hut is not very good for half-tone illustrations. Colored slides are highly recommended for this type of presentation; hence, the slides were colored either with colored light bulb paint or colored transparent tape (Chart-Pak). A good quality cassette tape is recommended, especially if the tapes are to he used for several years. Since a recording time of 30-40 min is required, the C-90 type was satisfactory as two lectures could he recorded on one tape. There are numerous tape recorders and slide projectors available; some of the former have built in projector synchronizers. The apPresented at the 29th Southwest Regional Meeting, American Chemical Society, EIPaso. Texas, December 5-7, 1973. 'Wendlandt, W. W., Geanangel, R. A., and Barry, D., "Chemistry, An Audio-visual Approach," University of Houston Press, Houston, Texas, 1973.
pmach used here was to couple a Kodak Carousel projector with a stereo cassette tape recorder using an Edmund Scientific Co. synchronizer. Conclusions
The progress of the tapelslide lecture technique was monitored periodically during the 1972-73 academic year by carefully constructed questionnaires. From the student responses, it was judged that this approach was successful as a lecture medium and, in fact, the students favored it by a two-to-one margin over the traditional lecture approach. This is perhaps not difficult to understand because of the time and effort used to prepare well organized and effective tapelslide lectures. Approximately eight hours of preparation were needed for each of the lectures, which included the slide presentation, taping, and numerous other details. However, much more time than this would have been required if a formal script were used for the tape lectures. Thus, this approach requires the ex-
penditure of a great amount of preparation time and perhaps should not be attempted by a single instructor but rather, a team approach as described here should be employed. As with every teaching technique, there are distinct advantages and disadvantages for the tapelslide format. Some advantages are: (1) inexpensive compared to CCTV or 8 or 16mm film; (2) better organized than the "typical" live lecture; (3) same course content can be used for multi-section courses; (4) may be used for several years without changes; (5) can be used for audio-tutorial instruction as well as lecture; and (6) lecture demonstrations can be readily illustrated. As for disadvantages, the following are perhaps pertinent: (1) no data hank of tape/ slide lectures exists commercially; (2) length of time needed for preparation; (3) removes personality of instmctor to a certain extent; and (4) interaction between student and instructor is decreased.
Volume 52, Number 2. February 1975
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