How to build a better mousetrap (in context) - Journal of Chemical

How to build a better mousetrap (in context). Jack L. Hedrick. J. Chem. Educ. , 1989, 66 (6), p 498. DOI: 10.1021/ed066p498. Publication Date: June 19...
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provocative opinion How To Build a Better Mousetrap [in Context) Jack L. Hedrlck Elizabethtown College, One Alpha Drive, Elizabethtown, PA 17022 The paper was read and drew a response of, "yes, hut he's not describing our situation." A common, casual mistake followed. A copy was made and placed a t the beginning of a set of notes for a quantitative analysis course. There i t resides t o be read a t the start of class each fall. Feelings of dismay increase with each reading, which, if extrapolated, intersect just this side of apoplexy in the year 1991. I'm referring to the paper that appeared several years ago in this column that the author titled, in his best Rodney Dangerfield voice, "We Analytical Teachers Don't Get No Respect".' The gist of the paper is given in the subtitle, "Maybe We Would if We Really Taught Analytical Chemistry". The author points out three shortcomings and two consequences associated with what he considers the typical content of an introductory quantitative analysis course. In brief, the shortcomings are: (1) too much time is devoted to aqueous equilibrium and titrations, (2) the samples analyzed are too simple, and (3) these simple samples are not typical of those usually encountered by today's analytical chemist. The resulting consequences include: (1) real-world analytical chemistry is not presented, and (2) a doubt is raised as to the value of analytical chemistry. After stating that the "challenges to the analytical chemist are not coming from other chemists" but from persons in other fields who need chemical information, the author exhorts us to include topics in the introductory analytical course that typify current practices in the field. I question how complex samples should be a t the introductory level and the implication that wet chemistry is no longer useful or necessary. Otherwise, I find myself in complete agreement with the author. That's odd. That's odd because I teach one of those terribly outmoded quantitative analysis courses he condemns. Much time is devoted to aqueous equilibrium in lecture, and a number of titrations are performed in the laboratory. Horror of horrors, there is

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even a good bit of time devoted to gravimetric analysis! I contend that within the proper context, the course that he describes, the course that I teach, is both suitable and proper. I t is the author's description of this course in isolation that leads to my dismay and consternation. So, let's take a look a t a suitable context. We first need to make some assumptions. Let us assume, hypothetically of course, that there is a small, respected, liberal arts college in southeastern Pennsylvania with a strong chemistry department. The six facufty members in this department have approximately 100 years of combined teaching experience a t the college level. Let us further assume that it is the early 1980's and that the college is about to construct a 2.2 megabuck chemistry facility. Let us also assume that this department is allowed an unbelievable amount of input into the design of the facility to the point of having almost a free hand within the financial and size cons t r a i n t ~ .What ~ a marvelous time for this department to entirely overhaul the chemistry curriculum. A top to bottom overhaul. A comdete housecleaning, not iust a fine-tunine of the present curkculum. My goodiess!-~hefaculty mGht even arrange . to have the building - fit thenew curriculum and vice versa. One other item is necessary to complete this preamble, the student audience for our hypothetical setting. Let us assume that this department has several tracks that lead in a BS in chemistry; the ACS-CPT approved, secondary education, chemical management, chemical physics, and medical technology. Yes, medical technology. Let us also assume that a small carload of biology majors enrolls in chemistry courses for two years. Finally, let us assume that there is a group of students who need a general chemistry course for various

' Hirsch, R. F. J. Chem. Educ. 1987, 64,438-439 Bent, H. A. J. Chem. Educ. 1986, 63.54-56.

reasons such as a liberal arts general education requirement or a major requirement in occupational therapy. We will refer to this group as the "others". Doesn't sound a whole lot different from vour situation does it? These, then,are the assumptions that provide the setting is manv for the context. Aeolden o ~ ~ o r t u n i t v~resentedthat academic chemists in highir educatron are never afforded,; chance to fulfill that fantasv of beine able to hake a curriculum cake from scratch. NO;, let's ta'ke a look at some of' the possible thought wocesses of our hwothetical band of six faculty membirs A d the conclusionsihat might be reached as manifested in the resulting curriculum. General chemistry has always been a problem for the department. What to do for beginning students who have an extremelv heteroeeneous hackmound and varied academic and professional interests? Of course, this is not a problem uniaue to this department. Students interested in maiorine in chemistry and biology are usually fairly well prepared: Thev are iust treadine water for a vear in eeneral chemistrv. a course fbr which textbook authois are i&easingly includ: ing traditional analytical and physical chemistry topics. More and better can be done for and with these students. But, there are still the "others". The conclusion is obvious. A general chemistry course must be retained but only the "others" will enroll in it. It follows that organic chemistry will he installed as the first-year introductory course for all chemistry and biology maiors. It will include most of those tonics associated with introductory organic. But, every so often when no one is looking, a few topics will he allowed to sneak in that are usually included in general chemistry. Topics such as electron configuration and eas laws. Whv not use oreanic as a first-year vehicle? M O S ~first-year chemistry an2 biology students are prepared for it. Other institutions have done it successfully. ~ e t ibe t done. A second-year course must be considered next, one that will both cap the chemistry curriculum for the biologists and be a logical steppingstone of continuity for the chemists. Dare a full year of analytical chemistry be suggested? The first semester will he a classic, wet quantitative analysis course filled with mavimetric and volumetric analvsis. - . inorganic nomenclature, stoichiometry, analysis of simple sam~ l e sand . lenethv discussions of aoueous eauilihrium. It will be, in fact, much the same course outlineb in the Rodney Dangerfield paper. This would allow for the introduction of a number of those topics usually included in the general chemistry course "missed" by these folks and at a higher level. To mention a few other positive aspects, a student can learn a lot of techniques, record-keeping, and data-processing skills in a course such as this. Now for the second semester of this analytical sequence. It will he an instrumental analysis course suitable for both chemistry and biology majors at the sophomore level. It will include t o ~ i c sin electrochemistrv. snectroohotometrv. chromato&aphy, and thermal anal&&. 'The &emistry ma: iors can learn the ~rinciolesand ooeration of more advanced instruments such-as NMR and x-ray diffraction in upperlevel courses. The biolom maiors can he introduced to more advanced topics in their &n hiology instrumentation course. What can he done withan instrumentalcourseat this level? Well, real-world samples can be incorporated into such laboratory determinations as quinine in tonic water, calcium in eggshells, fluoride in toothpaste, base content of antacid tablets, copper in an ore, simultaneous glucoseBUN in blood. riboflavin in a vitamin tablet..iron in a dietarv supplement, components of gasoline, analgesic tablets, and thermal characteristics of aspirin. It would also nicely allow

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for computer software applications such as spreadsheets, mathematical packages, and graphics. Indeed, these people would learn a good deal about real-world samples. r be a context in which a classical Doesn't this a ~ o e a to quantitative anaiysis course fits rather well? In four semesters. the students will have been introduced to a laree " maiority those topics usually included in six semestersof general. oreanic, and analviical chemistw. Sounds and looks orett y &d,and we coulh beset up fur iconclusion to this paper. But, readers who have iourneved this far will probablv not be satisfied until the remainder bf this hypothe&al cur;iculum with respect to chemistry majors is described. We go on. Physical chemistry has heen an odd duck in this department for years comprising three semesters rather than the usual two. The division into three courses. chemical eouilihrium and kinetics (thermodynamics), atomic structure, and molecular structure and mechanics will be retained. Scheduling will call for thermodynamics during the second semester of the sophomore year, the other two during the junior year for the ACS-CPT-track students. The other chemistry majors will enroll in one or more of these courses depending on their particular track and interest. The topic of polymers would he good to include at the junior level, hut the faculty includes no polymer chemists. How ahout teaching it as a full-year course in natural polymers. i.e.. hiochemistrv. with a laboratow? And. while we're at it,kh;not offer a second degree withi; the department, a BS in biochemistrv? This would satisfv the premedical and other health professions students as well as ihose interested in plain old biochemistry. Ready for another novelty at the junior level for all biochemistry and chemistry majors? Why not get into the spirit of the "writing and oral presentation across the curriculum" craze sweeping the campus and require a seminar course? Students can write a term paper during the first semester and present it the second. A "lahoratory" will he included during the first semester. The computer toolbox will he dragged out and topics such as on-line literature searching, word processing, and all those other nifty things that would aid the student in preparing a paper on a chemistry topic introduced. Part of the first semester would also he devoted tu faculty seminars in which research topics currently under invcstieation in the department are presented. Whv? Recause with this background, the students are for and most will he required to complete a final year research project and present the results in a senior seminar. During the senior year, the ACS-CPT-track folks will be enrolled in advanced inorganic and advanced organic courses. In addition, because a number of the courses at the junior-senior level have had no laboratory associated with them, one semester of an integratedlahoratory course will he required. There you have it. A complete package, well thought out so that the whole (curriculum) is eoual to more than the sum of the parts (cou&es).What 1;ve described, obviously, is not a hwothetical situation. I t is a short outline of a curriculum thit'we instituted in 1983, have fine-tuned just a bit, and seems to be working remarkahlv well. What's the point? The point is that many course can-be condemned if ii is considered in isolation. You can't do that! You have to look at a course in the context of the complete curriculum. And now for a pontification to my colleagues. Stop trying so hard to make the courses that you teach better. Start by first considering and getting your entire curriculum house in order. The content and methods that need to he included in your courses will then become much more obvious. This would seem to be the way to build a better mousetrap.

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Volume 66 Number 6 June 1989

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