Malcolm E. Kenney, Robert F. Toomey, and John R. Martin Core lnst~tuteof Technology Cleveland 6, Ohio
Closed-Circuit Television as a Supplement to the General Chemistry Program
During the academic year 1958-59 closed circuit televisiou was employed in the general chemistry course at Case as a means of augmenting the program, not as a method of displacing live instruction.' Supplementation and not replacement was the basic premise; this application of television required an increased teaching staff. Television was utilized in the lectures to show apparatus which was permanently mounted in research laboratories and enlarged views of experiments on the lecture table which involved equipment too small to be seen by the whole class.2 It was also used in the laboratory in connection with an experiment on the mass spectrometer.
Students viewing a te1eca.t of the moss spectrometer
The program was supported by a grant from the Case Project. Additional information on this type of demonstration is given by GLEMSER, O., J. CHEM.EDTC., 35, 573 (1958).
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Journal of Chemicol Education
In those lectures which were supplemented by television short periods of live instruction were interspersed with televised demonstrations, a procedure which called for rehearsals and careful synchronization. This was made possible by means of two-way sound and an independently manned two-way telephone. In addition it was found that smooth presentation required separate personnel for the television camera, the monitor, the slide projector, and the lights and continuity sheet. The following paragraphs outline the manner in which television was used in specific instances. Research Instruments. This demonstration was used to present the methods of operation of certain instruments, the types of results that they yield, and the means used to convert these results into the solution of research prohlems. The central theme of the lecture was the nature of MgO. In the course of the hour the students were shown a televised view of MgO through a light microscope, a televised view of an electron microscope in operation, a slide of MgO as viewed with an electron microscope, a televised view of a powder Xray diffraction unit, and a slide of a typical film from it. A short lecture was given for each of the instruments and it was shorn that the information obtained from these instruments together with additional information and calculations could be used to obtain a very accurate description of MgO in terms of its atomic arrangement. After this sequence it was pointed out that the atomic structure of certain materials can be approached best by other techniques. To illustrate this point the operation of a recording infrared spectrophotometer with a sample of ethyl alcohol was televised. Titration Curves. I n connection with the lectures on ionic equilibria a televised experiment on titration
curves was set up. It differed from the others in that it was performed in front of the class and closed circuit television was used to furnish each student with an intimate view of the ~ e s u l t s . ~During the experiment the students were given televised views of the buretpH electrode assembly and of the chart recorder connected to the pH electrodes. It was shown that points picked off the curves (NaOH-HCI, NaOH-HOAc, and NaOH-H3P04)were in agreement with those calculated according to theory. Polymers. Because of the availability of the polymer laboratory a t Case, it was possible to let the students see televised views of some of the equipment used for polymer fabrication and to give them some feeling for chemistry as applied on an industrial scale. The lecture was built around the chemistry involved in the conversion of coal, water, limestone, and salt into finished polyvinyl chloride objects. During the lecture the students saw shots of a roller mill compounding raw P.V.C. resin and of an injection molding machine making milled P.V.C. into finished objects. The operation of a vacuum former was also televised. Mass Spectromekr. This was the only attempt a t using closed-circuit television in the laboratory and was based on the idea that more interesting and informative freshman experiments could be developed by making
a wider range of equipment available for use. The mass spectrometer was chosen as the subject of the dernonstration because it is an instrument that givesinformation which is meaningful to freshman and yet one that is ordinarily out of reach. I n the experiment the students were given views of the instrument while the mass spectra of methane, a chlorinated hydrocarbon, and a mixture of the two were being obtained. The data that the students thus gathered, together with additional information, enabled them to identify the major peaks of the spectra and to calculate the isotopic ratio for chlorine and the composition of the mixture. Closed-circuit television made it possible for the freshmen to see in action instruments and equipment that under ordinary circumstances must be reserved for the use of upper classmen. This stimulated interest in chemistry and enlarged the scope of the freshman program; as a result it is felt that the project was a success. In general, the students seemed to respond favorably to television under the conditions of this project. It should be reported, however, that the total cost of the program was too high to allow for the wholesale use of this type of lecture demonstration. Inasmuch as television equipment was readily available on campus the major portion of the expense was in the preparation required by the experiments chosen for use.
Volume 37, ~ u m b e r . 5 ,Moy 1960
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