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A DEMONSTRATION MODEL OF ATOMIC STRUCTURE VINTON R. RAWSON and ROBERT W. PFEIL Senior High School, White Plains, New York
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SERIOUS objection given by teachers to presenting and visible from all parts of the classroom. Unlike atomic and molecular structure early in the general three-dimensional models, their simplicity makes them chemistry course is that the material istoo difficult and is easy to understand. It is, of course, emphasized that uninteresting. Neither of these reasonsis true unless the these hoards show only conventional diagrams. Some teacher makes it true. If the teacher knows his subject .students later bring in three-dimensional models to material thoroughly and is willing to spend some time show that they have given much thought to this real on demonstrations, this unit can be a most interesting structure. one. If well taught, this material is no more difficult (5) If possible, make field trips to science museums t o master at the beginning than later in the course. and to college physics laboratories where nuclear The following are some suggestions of ways to vitalize experiments are performed. this unit,. (6) Review the unit with the aid of a good motion picture film or a film strip. (1) Use your bulletin board. The model boards may be made from 3 X 3-ft. (2) When discussing the parts of an atom, raid the physics laboratory for any available equipment to squares of plywood x h ~ c hare screwed to 1 X 2-in. demonstrate the presence and properties of these par- frames to prevent warping and are painted a dull black color. Concentric white rings and eight radiating ticles. blue lines are painted on the boards. The circles are Show the small size of an atom by having your (3) students calculate the length of a much larger molecule lettered out from the center of the boards I
