JOURNRL OF
Chemical €ducation: Software Abstracts for Volume ID, Number 2 Bonding Theoryfrhe WernerJergensen Controversy David M. Whisnant
Wofford College
Spartanburg, SC 29303-3663 This two-part simulation introduces students in heginning chemistry courses to the process by which concepts of molecular structure and bonding developed during the 19th century. The aim ofthe simulation is to help students discover that there is more to learn about science than just the theories, fads, and pmblem-solving methods usually presented in the classroom and textbooks. The proeess of sciencehow scientific change occurs and how scientists behave--also can be very interesting. This program, which originally was written for the Apple II ( I ) , has heen extensively revised to NU under Microsoft Windows 3.x using ToolBook 1.5. The new version includes not only a story-line that leads students through nearly 100 years of ideas about chemical bonding, but also a hypermedia database that presents extra information about the theories and the chemists who were involved. Hypermedia offers students many paths in which to move around the simulation and gives them a greater sense of exploration than was possible in the older and more linear version. The new version also is much improved visually. One of its goals is to see the development of bonding theory through the eyes of 19th century chemists; the realistic pictures of many of these chemists create an atmosphere that furthers this goal. The simulation is divided into two parts. The first develops Berzelius's idea of dualism, the radical theory of organic compounds, the breakdown of dualism, and the rise of the concept of valence and tetrahedral carbon. This is done through computer-simulated interviews with Berzelius, Wohler, Dumas, Liebig, Gerhardt, Frankland, and KekulB. Students are asked to formulate structures using each of the theories so that they can better appreciate how the theories worked and why they ultimately failed as new compounds were synthesized. This part is based upon descriptions of the period 1810-1860 given by Ihde (2)and others (3-12). In the second part of the simulation students learn about the chain theory of Blomstrand and Jorgensen and Werner's coordination theom, Thev then are challeueed to compare the two theoncs a i d to defend their choireiased won the conductivitv results of Werner and M~oIntiI 136. I&) and on differences in the prediction of numbers of iso: mers (13a. 13b). The ex~erimentalresults available change during the simulation-ne isomer is not prepared until students have worked throuah the corn~arisunofthe two theories. At any time d u r i g t h i s part,-the students can obtain guidance from Werner and Jorgensen to help them in their choices of interpretation of the data. The simuation includes pop-up questions that help direct student exploration and provide a means by which their level of success can be evaluated. The questions 902
Journal of Chemical Education
Sophus Maos mgensen maws a sLggeslon regaro ng coora naton theor) n Bond ng Theoryfrne Werncr-srgensenControversy posed also encourage students to think about the connections between the simulation and modem chemistry and about the process of science. With respect to the latter, one section of the hypermedia database includes a discussion of Thomas Kuhn's portrayal of scientific revolutions (14). The complete simulation provides a hands-on introduction to the methods of science and the behavior of scientists that is far more realistic than most textbook discussions of the "scientific method". Acknowledgments The author is grateful for the assistance and helpful suggestions of Terry Fekguson. Partial support for this work was provided by the National Science Foundation's Instmmenktion andI,al,onitory Improvement Prngrnm through grant li USE-9151873.The author alw thanks the BellSouth Foundation for partial support.
Enriching Quantum Chemistry with Mathcad Frank Rioux Saint John's University Coilegeville, MN 56321 Mathcad is a comprehensive, inexpensive program for doing numeric and symbolic mathematics on a computer. It runs under Windows and has an appealing, userinterface. Mathcad has a wide varietv of friendly - .ma~hical . . appllcatlons in the undergraduaw chemistry curriculum, but is rspeciallv useful in the mathemirticallv intensive courses &aditiohally found in the physical chkmistry sequence. (15, 16, 17, 18) As the title suggests this module presents applications of Mathcad in the area of quantum chemistry. Students generally fmd quantum chemistry to be highly mathematical, quite difficult, and very ahstrad. They are right on all counts. However the subject is also extremely important today, even at the undergraduate level. There is, therefore, a need for relatively simple computer exercises that bridge the gap between the formalism of quantum theory and its various computational methods (19).All of the Mathcad documents presented here attempt to do this in one way or another. Some exercises involve relatively
