Computers in Chemical Education; Yes, No, or Yes.
..If?
I provocative
The ubiquity of computers is evident to all who look; their utility in honest chemical education is not as apparent. A computer is a device which can do anything one is able t o tell it to do; but ability and imagination do not always reside in t,he same chemistry professor. This is a plea, t,o t,hose who are able, to consider the awesome results of a lack of imagination. The trouble with computers is that it is a simple matter to program in fixed answers, to which student,sJansxers are mat,ched, and t,hat it is at. least an order of magnit,ude more difficult to program in a st.rat,egywhich permits st,udents to make their own unique contributions. Rigid attention t,o the professor's right answers, st,ored in the computer, as a measure of student competence in ehemist,ry fails to recognize the validity of individual student answers as a measure of student progress. Consider, for example, a freshman chemistry lab exercise in the determination of the molar volume of oxygen. Indeed, there is only one right answer. Indeed, we can program t,he computer to accept a certain slop in the student's data. But is it true that a student should receive a computer grade for his work which is solely dependent upon how close he comes to that range of right answers? The objective of laboratory instruction, surely, is only slightly related to this criterion. I n a physical chemistry oriented lab opportunities abound for curve fitting, and a least squares line is much admired. So some students are now encouraged to enter their raw dat>ainto a computer and receive in return the slope and intercept of the least squares line. I n other cases, the student is required to work out the slope and intercept manually, by the old arithmetic process, and after he is successful he is allowed to subsequently use a computer to do the work for him. I suggest that neither the mindless nor the sadist,ie approach represents effectiveuse of a computer. Homework, end of chapter problems, and other similar drills seem to be made for comput,er checking. The student need only punch out the right answers from a pre-punched card, turn it in, and the record of his presumed performance accumulates. Multiple choice question examinations have been graded for years now by computer. With the increasiug availability of computers on each campus, this practice will undoubtedly increase. Few object to carefully written multiple choice examinations today, but a real danger of proliferation of true-false quest,ion sets, masquerading as multiple choice questions can be forseen. Computer-assisted instruction can be well done. It can also merely be a page turning device for an intrinsic programmed instruction on a giveu topic. Such use is a travesty and a waste of both the professor's 758
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Journal of Chemical Education
opinion
time (when he writes such a program) and a cost,ly use of computer time, to say nothing of what happens to the student. Even worse, some are now suggesting that to minimize the professor's time it is reasonable to rigidly stylize the format in which the computer output to the student is presented; in effect, to write such an intrinsic program for the computer the professor need only fill in the blanks. What comes out, what the student sees, resembles the "Look, Jane, look Tim, see the brown dog" that was eliminated from elementary readers some time ago. Let us not go through that again! I suggest a criterion by which to determine whether a computer should be used in any giveu way, ot,her than keeping of records generated by other means, in chemical education. Computer programs used to teach or to evaluate must possess one or more of t,hesethree features 1) Built& provision for personal professor-student interaction involving either what the computer "said" to the student or what the student provided as computer input, or both; such interaction to be either individual, professor and one student, or diverse, professor and a. smell group of students. 2 ) Opportunity for the student to exercise his own initiative without any risk of negative evaluation as %result;andif possible, the opposite, computer "recognition" of even chemically naive initiative as a signification of some slight competence. 3. Any two students who put in the sameinput to the computer will receive different computer responses to that identical input, even when it is the same student who does it twice as though he were a second student.
Some examples do exist of computer usage which meets this crit,erion. Since my purpose is to stimulat,e emulation, not t o record, the examples below are neit,her complete (others could have been cit,ed) nor identified by named sources. Multiple choice questions can now be partially graded; some of the choices can be half right,. I t is not tedious to find out if a given multiple choice quest,ion was correctly answered more often by students who did poorly on most of the other questions t,han by those who did well; and to confer with students later to find out what the professor did in his statement of the cluestion to produce such a result. Opportunit,y can bc provided for some student-generated response, computer evaluated, when some multiple choice questions are answered. Essay question examinations can be graded by computer, and the time saved on the professor's part used to critically and individually evaluate the same answers from a fraction of the whole class. With the advent of inexpensive time-shared terminals students can take an exam a t the terminal, and receive immediate comment from the computer about the answer they have selected from a few choices, or the answer they have giveu in essay form. Such examina-
tions can be taken a t any time; there is no longer any need to set the whole class in mild turmoil a t an appointed day and time. Students can practice analytical techniques on a computer, and be taught to select a suitable weight of primary standard, to prepare enough only, not too much or too little, of a standard solution. I n a titration, the computer generated results can be realistic, with successive titers on comparable aliquots varying a fraction of a milliliter in successive runs, with no two students ever getting the same set of data. Homework on Porta-Punch cards can make provision for checking of intermediate steps as well as the final answer; and the student's actual work written on the card as well, for occasional individualized evaluation by the professor or his assistant. We have taught problems involving equilibrium concepts for years by telling students to neglect small numbers in an additive or subtractive term in order t,o avoid the tedium of solving quadratic equations. At a shared time terminal the student can ask the computer to solve his quadratic iteratively beginning with the student's first guess of the value of the quantity in question. And the computer can respond by carrying out that operation or by informing the student that his guess is chemically preposterous. Variations of this are multiple; it need not be restricted to only equilibrium-quadratic problems.
Instead of only evaluating the student's claim t o know the molar volume of oxygen, the student can be asked questions about other features, what is the color of IC103, how can you be sure that there was no air mixed in with your sample of oxygen, is it proper to subtract the pressure of the water vapor from the total pressure of the gas you collected over water when you have no evidence that the collected gas was saturated with water vapor? At the minimum, perhaps, no high grade would be given t o a student who got the "right" molar volume, but was unable to answer some of the more introspective questions. It is too easy t o use computers to only evaluate simplistically correct answers, it is almost as easy to write routine intrinsic programmed instruction and call it computer-assisted instruction. Indeed, it is true that no professor can teach; that is the task we set t,o the student, each one, on his own. But we can help our students in their work best by working harder ourselves to put imagination as well as our own right answers into the computer for our students to use. Unless we supply our own version of imaginative utility, we cannot rcquire the student to do the same, later. If chemistry is not imaginative, what is?
Jay A. Young Auburn University Auburn, Alabama 36830
Volume 47, Number 1 I , November 1970
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