Distillation: simple and fractional - Journal of Chemical Education

Nov 1, 1982 - Journal of Chemical Education. Campbell. 1962 39 (7), p 348. Abstract: This experiment demonstrates in a practical way the factors invol...
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media exchange As the daily newsDaDers react t o scientific news and even headline it onihe front bares, 1 become more convinced of t h e importance of chemistry for ail high school students. T o understand the reasons fo; placing crhemicals in our foods, gasoline, cosmetics, clothes, and drugs, one needs chemical knowledge. T o understand the effects of chemical warfare, the energy "crisis," insect control on our environment, one needs some study of chemistry. One hears about rhemiral carcinogens, chemicals to control depression, and the"evils" of illirit drugs. T o understand these claims, one needs a knowledge of chemistry. Within this column we try to review a multitude of materials that will be useful to your students and help you t o explain chemical concepts. Films and filmstrips, computer programs, and other media do not replace you, the teacher, but are intended to become an integral part of your lesson plan. Just as you integrate demonstrations to make a point, media usage should he part of your lesson. not the focus of a class oeriod. The conceit is the focus andeverything else just makes the learning a little bit easier. I never feel obligated to use a film or filmstrip from start to finish, hut ratier the footage or frames that are especially applicable to my lesson become part of my lectures. Any lesson could have a one-minute segment of a film, or a few minutes of slides as part of the class period. Slides prove to he especially useful since they can be removed from the sequence and used entirely at your discretion. In fact, you might consider a multimedia set-up which would include a tape recorder, film projector, and overhead projector. Admittedly, this takes some planning a t the beginning of the year, but once done, voila, you are ready for the entire vear. The following filmstriplslide set is a case in point. There are Hemp excellent slides that would fit within agrent number of lessons, although ir was produced for n lesson on distillation. In fact, this in true for almost all media materials. and if vou are aware of this while you are viewing the material, you will find a great number of uses for them.

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Distillation: Simple and Fractional Tlme: Format:

Approximately 30 minutes Filmstriplslides in color Cassette tape with audible advance signal Cat. No.: YQ9173FS Price: $99 Supplier: Prentice-Hall Media, Sewcode WL, 150 White Plains Rd., Tarrytown. NY 10591 This is an excellent filmstrip that demonstrates very clearly the laboratory techniques involved in distillation. which ran be a frustratihg experience if the equipment is not handled properly. This set provides a good opportunity for students who have missed the prelah discussion or the lab itself to observe a well-done laboratory procedure. Of course, the actual lah experience cannot he r&laced by this filmstrip, but it is superior to having the student get the information from a friend or not get it a t all. You might also want to consider integrating the filmstrip into an actual demonstration. By leaving the sound off and utilizing appropriate slides, the instructor becomes the narrator in the demonstration. 982

Journal of Chemical Education

HARRIETG. FRIEDSTEIN Rochester institute of Technology 50 W. Main Street Rochester, NY 14614

The frame showing the positioning of the thermometer in the distillation tube is especially clear. The ex~eriments chosen to be illustrated are comrnon ones using standard equipment found in most high school laboratories. The concept of boiling point is explained using methanol. This is extremely well done. Another point examined in this filmstrip is the comparison of the actual boiling point curve of methanol to the ideal curve. A good discussion of the difference is presented. Accompanying the series is a booklet with the complete script plus suggestions for use. At the end of the booklet. ten quekibns andanswers are printed and this can he used'as a quiz if the teacher is so inclined. There are only two minor complaints which could probably he remedied by the classroom teacher. First, the parts of the distillation apparatus are not labeled, probably under the assumption that most students are familiar with it. Second, the narrator becomes a little too verbose during the course of a few frames. This minor distraction causes the student to focus on a single frame for a longer time than preferred. This is basically a good set and worth purchasing if you incorporate a distillation experiment into your laboratory schedule. On the other hand, it might he worthwhile to include in your filmstrip library for use as an "extra" assignment because of the importance of distillation in the everyday world.

The Periodic Table Time: Format: Price:

24 minutes 16 mm film and videocassette $445 for film, $310 for video cassette, $50 for rental, Cat. No.: M56104 Supplier: The Media Guild, 11526 Sorrento Valley Road, Suite J, San Diego, CA 92121

This f h , produced by Open UniversityBBC-TV, is the fmest chemistrv film to hit the local classroom in vears! There - ~ ~ is a beautiful hiend of well-consideredchemical prinriples and whimsv which orwides both humor and better understandine of chemical pe;iodicity. Many chemical reactions and sever; physical properties are discussed as students are led toward the "modern long-form of the periodic tahle." This film recently won a Blue Ribbon in the Science Division.

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GORDON E. MDRLAN Grosse Pointe North H.S. Grosse Pointe. Mi 46236

This feature wiii allow for extended coverage which wiii include ail insbuctionai a* (0.g.. games. madeb, kits, charts, M l e t s , bradlwes, and. of course. the standard audiovisual items). With the large volume of print and A-V materials available and the limited budgets of most chemistry departments, this exchange offers a valuable service. if you are interested in assisting in this process, send your name and address to the feature editor.

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