mnething new horn the paft "Should Orbitals B e T a u g h t i n High School?" James J . Morwick, J. CHEM. EDUC., 56 . 141,262, (April 1979). . In the September 1980issue of THIS JOURNAL, I mentioned Morwick's article written for the Hieh School Forum. edited hv J. D. Herron. Yaw, at the brg~nn~ng of the school year. with atomic theory and s t r u ~ t u r rappearing earls in m u ~ tcurr~culain ~ntruductUry chemistry courses, this timely article bears repeating, but in more detail. Momick begins with two arguments against the teaching of orbitals. (1) The concept is too abstract. (2) Time could be spent on some "real" chemistry. But then he goes on to argue why the critics are wrong. However, before those of you who teach orbitals either at a "handwaving" level or by actually delving into the mathematics of quantum theory, please take note of one important statement made by Morwick. ". . . [students] do not get excited by a curriculum [orbital theory], hut by TEACHERS." True, students can be turned on by theory, but theory developed in a cogent way, taught by an authentic teacher can almost assuredly win students to the disciplinesof science. Morwick's insights to the problems associated with the teaching of orbitals a t the beginning level are deep. His arguments pro and con are sound, but his overall message is one to be heeded, particularly by those teachers who like to "wow" their students with their own theoretical prowess. He says that orbital theory "can and should be introduced in high school even if only in an uncomplicated way. In fact. it is this uncomnlicated introduction that makes it nossible to return ir, it later IBrunrr's idras ot sp~ralcurriruluml, and to study rt again, absirwily and mathemat~rnllg,in univrrsiliei IPiagrtl." ~
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References on t h e Aufbau Principle "The Filbleof the AtumicTheawr," Milton Kerker. J. CHEM. l h r c : . , 34, 111,. 32 (January 1957). Kerker presents a blackboard model that is interesting and useful. He says that "the theater is partitioned into agridworkofshellsand subshells which are designated as 1, 2, 3,4, 5 , 6 , 7, and s,p, d, f , respectively. A block of seats can he located by specifying any two of the three quantities-shell, subshell, and period-and also whether it is on the right [odd-numbered] side or left [even-numbered] side of the theater." "An Orbital Notation Memory Device," Theodore F. Patchen, Chemistry, 47 181, . . (September 1974). Patchen says, "To relate chemical and physical properties to electron structure, electron configurations notation is sufficient. But to study bonding between atoms, orbital notatton is more useful." "A Demonstration Model Illustrating t h e Aufbau Principle," D. H. Everett, J. CHEM. EDUC., 36 [6], 298 (June 1959). Everett says. "The model described . . . Has developed . . . 1,) demunstrate how, by application of the A u h u principle, m e ran show the relationship between the relative energies d alrrlron orhitah in many-electron atoms, the electronic structure of atoms, and the periodic table of the elements." Everett's model, constructed on a large hoard held in a vertical position, uses ball bearings as electrons which are fed in at the top and run down through the energy levels (periods) until they stop, "fill," a t the lowest level. The energy levels are metallic troughs, each mounted slightly tilted to cause the hall hearings to roll down. When each energy level is completely filled, a mechanism is tripped to stop the balls at the next higher level. It is an ideal device to have some of your students construct for classroom use.
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Journal of Chemical Education
Edited by: JOSEPH S . SCHMUCKLER Chairman of Science Education Temple University 345 Riner Hall Philadelphia. PA 19122
"Aufbau Principle: A Simple .Model fur L)emunstratim." Seetarama Raju Sagi, J. CHEM.EIXC., 47 191,648 [September 1970). in cmtrmt to wooden or .tgrdi,am models, Sdri has
