Clifford G. Venier and Manfred G. Reinecke Texas Christian University Fort Worth, 76129
Armchair Unknowns A simple CAI qua1 organic simulation
For the past two years, the undergraduate organic chemistry course at Texas Christian University haa used a simulation of organic qualitative analysis as a teaching aid. Recent interest in techniques of this kind (1-5) prompts this report of our method and experience. Smith (I) has described this type of simulation utilizing a dialogue format between student and the elegant University of Illinois PLAT0 system. Hornack (2) and Sherman (3) have described a system smaller than but similar to our own which is on the North Carolina Educational Computing Service network. Culp (4) a t the University of Texas a t Austin has developed a keyword recognition dialogue course. In a related program designed by Gasser and Emmnns (5), the computer is used solely for sorting and comparing actual laboratory results with properties of the compounds stored in a data bank. Our own system derives from that described by Swets and Feurzeig (6) to teach medical diagnosis, a subject which requires the same type of thought processes as organic qualitative analysis. The underlying idea of this computer exercise was that a real patient need not die while a novice learned diagnosis through correction of his mistaken inferences. In an organic qualitative analysis simulation, the student need not be burdened with shortcomings in his laboratory technique while trying to build a logical framework on which to exercise his reasoning powers. In other words, the computer can supply entirely reliable data; the student need only supply its correct interpretation. Hopefully, the student will gain sufficient confidence in his reasoning ability that when he begins actual laboratory work he will be able to decide if a particular inconsistency in his results is due to a mistaken inference or to an experimental error. Ordinarily, the average student requires about 4-6 weeks (4 hr of lab/week) to develop this critical ability. The purpose, then, of Armchair Unknowns is to teach the logic of qualitative organic analysis more rapidly and better than is possible in the traditional wet laboratory. Being inexperienced in the use and programming of computer-assisted instruction, we have also attempted to keep things as simple as possible, consistent with our goals. For this reason, the simulation was tied to a single text, R. L. Shriner, R. C. Fuson, and D. Y. Curtin, "The Systematic Identification of Organic Presented in preliminary form to the Conference on Computers in Chemical Education and Research, Northern Illinois University, July, 1971, and to the American Chemical Society Southwest Regional Meeting, Division of Chemical Education, San Antonio, Texas, December, 1971.
Compounds," 5th Ed., Wiley, New York, 1964 (SFC). This text is the most popular and widely used of its genre. Its 3000 unknowns provide an extensive, yet wisely limited set of representative unknowns. With a limited set of tests and no spectral information, it is often difficultto distinguish a particular compound from all of the other millions of known organic molecules. Coded responses tied to a particular text are far more easily progammed than the very sophisticated dialogue described by Smith ( I ) , yet allow immediately a far more extensive set of experiments and unknowns than the program described by Gasser and Emmons (5) or Hornack (2). Shriner, Fuson, and Curtin, as a text, is easily coded (see Table 1). All in all, there are about 130 tests which may be run on an unknown. The program itself is presented to the student entirely in the first two weeks of the semester. This is imperative since they must have confidence in their logical approach to their laboratory unknowns as soon a3 possible. This procedure has the added advantage that other CRT users usually don't need computer time during the first two weeks of their courses, allowing one to have 20-30 hr of time each of the first two weeks. The student is first instructed and drilled in the use of the keyboard and light pen, then taught the codes and Table 1 .
Explanation of Student Responses Coded to Shriner, Fuson, and Curtin
1. Compounds (unknowns) we given taas, mm-nnn-z, where mm
is an indeiin c& of multiple listings under mm-nnn, simply
Its code ;s 4;;-34-2 ~eth;l'benzvl ketone 1s the first. and point g
