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Home  / GENERAL CHEMISTRY Textbook / Preface / James Spencer's viewpoint

James Spencer's viewpoint

James Spencer (Task Force chairman) published a report in 1991 on the results of the work of the Task Force in the JCE (No. 3 p.182). According to Spencer:

"General chemistry has been the subject of countless symposia, meetings, and conferences over the past 30 years. There is little left to be said about the course that has not been previously said. The pitfalls have been noted, various philosophies debated, delivery and assessment have been treated in detail. Nothing much has come from all this attention. Never before, however, has there been such a consensus movement towards a reconsideration of the general chemistry curriculum.

"The college general chemistry course is crowded with respect to the number of topics it covers. This is true despite the oft-cited criticism that the curriculum of introductory college chemistry attempts to cover more topics than students can be reasonably expected to learn.

"There are no guiding principles for general chemistry. We need to ask what we should do in the classroom and laboratory and why we should do it. Why are we teaching this? What do we hope to accomplish with the students? What are the desired outcomes? Why are there no behavioral objectives for the instructor? We lack a framework.

Textbooks are too thick because we have no common core, no agreed-upon set of principles, and no teaching strategy.

"Is it possible that we try to teach some things that are unteachable at the general level? Perhaps the phrase "presently unteachable" should be used. If there are topics that need to be mastered, we need to find new ways, appropriate to the general level, to teach them. There are some presently unteachable things that could be taught if we are willing to spend more time on that subject and less on another. Some of these topics are listed in Table 1.

"Consider, for example, standard free energy. The statement, "If ΔG is negative — the reaction is said to be spontaneous; and if ΔG is positive —  the reaction is non-spontaneous." appears in numerous texts. Aside from the questionable usage of the terms 'spontaneous' and 'non-spontaneous' — I have seen it written that 'the more negative is ΔG, the more spontaneous is the reaction' — the statements are generally incorrect. Note further that ΔG itself has a very restricted usage. The conditions must be that T, P are constant and that non-pressure volume work is not permitted.

TABLE 1

Topics Requiring Careful Consideration before Being Taught in General Chemistry (or, What is Unteachable at the General Level)

Calorimetry

ΔG°

Phase Diagrams

Ksp

Atomic Spectra

Quantum Mechanics

Colligative Properties

Schroedinger Equation

Clausius-Clapeyron Equation

LeChatelier's Principle

"Why do we introduce ΔG at all? Presumably so that the equation ΔG = -RT ln K can be introduced. Can we teach the concepts without ΔG? I think we can, and I think we should because principles first learned are most difficult to unlearn. If we believe standard free energy is essential, we must teach standard states, we must introduce the relation: ΔG = ΔG0 +RT ln Q in some manner; but does this not go away from an introductory course and over into something else? We believe we must simplify ideas so they can be learned for the first time. These simplifications are remembered more easily than correct descriptions.

"We ask students to 'fill in' the appropriate numbers and calculate ΔT or molecular mass. We are guilty here of wanting to do a calculation; rather than teaching the concept we calculate. I believe that one reason we do what we do is because of the ease of testing. Conceptual understanding is more difficult to test than numerical plug-ins. Content-oriented exams reward memorization; exams should reward understanding of process and concepts (2).    

TABLE 2
Topics that Might Be Better Reserved for Later Courses
(or, We Should Not Answer Questions Until We Ask Them)

MO Theory

CFT/LFT

Hard/Soft Acids-Bases

Statistical Thermodynamics

Metal Carbonyls and the EAN Rule

Nomenclature for Compounds with a Bridging Ligand

P.S. Table 2 contains topics that might be better taught in a later course.

  

TABLE 3
Topics that Are Not Necessary for General Chemistry
(or, Why do They Need to Know That?)

  Balancing Redox Equations

The Saponification Value of a Glyceride

Extended Buffer Calculations

Metal Clusters

Valence Bond Theory of Complexes

Geometrical Isomerism of Coordination Compounds

Iodination Number

Declaration and Shapes of MOs

Band Theory of Metals

"The final question I want to raise could be the guiding philosophy behind everything we teach: Why do they need to know that? In this context a careful consideration of what we are attempting to have the student take away from the course must be made. Do we teach some material because it is easy to test? How is the student supposed to be changed after encountering this material? Some suggestions are made in table 3 for topics that perhaps students do not need to know after a course in general chemistry.

"Before presenting any topic at the general level, these questions and others should be asked: Has this material been simplified to the point where it has lost all integrity? Are we answering questions before we ask them? Why do they need to know that?

"Philosophical arguments about what is essential or desirable in general chemistry are not new, but little progress has been made in addressing new directions in this curriculum. There are always those who say "we, who want a change, are trying to make the course easier." This is not what I advocate. Chemistry is a demanding subject — it will remain so. We must set high goals, but those goals must be attainable; and having been attained, must have been worth the effort. Removing material that is basically incomprehensible/unteachable may, in fact, make the material in the course more attainable because by doing so, we may focus more time and attention on certain topics. But the course should not be made less demanding.

"I think it is inconceivable that we, as chemists, can't agree upon a few basis concerns that could constitute a course. One very important aspect for me, and it could be the sole aspect of certain courses, is that the students understand that science is not a collection of facts, that science is a method.

"Because chemistry is hierarchical and requires vertical development; the course should provide some preparation for higher courses. The idea, however, that there is a certain amount of material that must be covered, is not as important as covering less better. We have been constrained, in part, by what we think our advanced courses and other disciplines expect of us. I do not believe we should slavishly follow a certain content. It is better that the students understand what a saturated solution is than to be able to do calculations. No student should leave general chemistry without knowing why chemists believe in atoms.

"Students should get an understanding of the macroscopic picture of nature and the structure of matter, properties of elements, their compounds, and their reactions. Students should have a sense of the overall structure of chemistry. That is, they should have a sense of the microscopic structure and properties of matter that allow chemists to explain, predict, and control macroscopic properties of matter.

"There is no approach that is likely to meet all requirements, but a core curriculum supplemented by modular material, may meet many objections. The core approach assumes that there is a basic set of concepts/principles that every student who takes the course should know. Once this core is defined, the core is supplemented.   

"A thin book — if such things exist — containing guiding principles, basic knowledge, a thematic approach to general chemistry, would be prepared."   

Chapter 1.Preface>>
James Spencer's viewpoint 
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