Content of final examinations used in the first course in college chemistry

A study was done to determine the frequency of topics that appeared in first year examinations. Topic frequency was compared between exams given in ...
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Robert H. Goldsmith Mary's College of Maryland St. Mary's City, 20686

Content of Final Examinations Used in the First Course in College Chemistry

The question as to what topics are included in the first year college chemistry course has been pursued intermittently over the last two decades. Nechamkinl in 1961 used a formal scale in which preselected topics were rated according to their desirability for inclusion or exclusion in this course. A recent uvdate of this annroach hv Jones and Roswel12 was done in 1973 and ascrideh greate; importance to such theoretical t o ~ i c sas free enerav. thermodvnamics, auaotum numbers, and thermochemic~l~equations~ while it also showed lesser importance for descriptive chemical topics. An alternate approach was taken by Jay Young3 in 1964; he believed that the rating of topics was somewhat subjective

in that i t gives as much credence to what the teacher thinks should he taught as to what is actually being taught in the course. He proceeded to study the problems and questions actually used in selected fmal examinations which he believed would better capture what was really done in the course. He secured 52 sets of final examinations containine 5600 auestions for the academic year September 1962 to ~ & 1963 e kom 100 randomlv selected colleaes - and classified the ouestions. using a topical list. It was decided to repeat this study using this methodology to determine if any trend could be found in a comparison of questions used in 1962-63 and in 1974-75, employing the topic

Frequency of Topics Appearlng on Flrst Year Chemistry Flnal Examination fi7-9'

(44.9%)

Fundamental Kinetic-Molecular theory Pericdic table Bands Valence, oxidatim number Structure, bulk" Structure, molecular' Structure. atomic s,p,d.fnotation Emission spectra Ionization potentials Other' Laws9 Intensive properties Stoichiometry The mole, equivalent wts Mathematical problemsh Concentration, titration Logarihms, p a s operator Other Applied Themdynamics Essential principles' General applicationsJ Gases Solutions* Homogenous equilibrium Heterogenous equilibrium' Phase rule Vapor pressure Boiling point Freezing point Solubility product EMF potential Half-reactions Nernst equation Otherm

67-9'

7 ~ f r b

Kinetics Rate constant Activation energy Electrolysis and conductance Other

(4.0)

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"New topic not inclded in earlier study.

100 1 Journal of Chemical Education

(5.1)

Descriptive General Inorganic Advaned inorganic Organic AdYan~Bdorganic

Anatyticai Chemistry Oualitatke, inorganic Qualitative, organic Quantitative Instrumental"

Other Toplcs Elementary chemical physics Nuclear chemistry Surface chemistry Biochemistry Practical chemistrv

2.1

1.3

Polymer chemistry"

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In3tilutionsstudied numbered 52 rchaols which avbmined 5800 ovebtions to be classified. %stitutions studied numbered 45 schoois which submlned 6148 duestions to be classifisd. Tercenisge of the total number of examination questions by topic. Figurer far major headingt (in parentheses) are the sums 01the subheading parenmeses. dcrvrtal structure. amomhour solids and liouida. X-rav dinraction. %OmeriSm. diolropy, magnetic propertiss. 'Pauii exclusion principle, atomic radii. ianthanlde conb-action.

iHenry's law. Rodt's law, La Chatelier'sprinciple

7LSh

0.4

list developed by Dr. Young. Another question of interest was whether the four areas of medicinal chemistry, polymer chemistry, instrumental analysis, and particularly environmental chemistry had gotten into the exams or not. So these four items were added to the original list of topics. Requests for copies of the final examination used in the first year college chemistrv course for the academic vear Sentember 197PJune 1975 were sent out to 170 i~isritutionsand 52 responses were received. of which 45 sew of final examinations were used for the study. The questions were classified using the topical classifications of the original tahle. Items were classified as specifically as possible under one of the specific topics or subtopics. For example, the problem of the common-ion situation is classified not under solubility hut under solubility product; phase diagrams are listed under phase rules. Another point made in the original study was that there are obviously topics that do not appear specifically in this compilation because they are included under one of the listed topics or suhtopics. The theoretical aspects of gas diffusion, for example, are covered under kinetic-molecular theory. It is recognized that any classification system cuts a fine line between too general and too specific, but it is hoped that most persons would agree with the majority of designations which have been made. Certain nebulous areas, which were of concern in the original study, have heen,of necessitv, rlarified hy the use of notes. Each note following the tahle gives more detailed information about a particular topic or u subtopic. Data on thesi7eof the institution and its location werealsu requesred from each school. Se\.en institutions were from the Far West, California: six were frum the Norrh-Cenrral, west of the .Mississippi; four were from the North-Central. east of the Mississippi; fifteen were from the .;outh:and thirteen were from New Kneland and neirhborine states. Georm~hicnll\,. this sample is\eighted toward the eastern half i f the coun: try. About one-third of the participating schools were medium sized schools (3000-8000 students) and slightly more than 4096 were from small colleges. Since the majority of schools in the United States are small. the selection of schools is com~atihle with this reality. A few schools indicated that their final examinations were not comprehensive in that their final specifically emphasized the material that was most recently covered, especially the material covered since the last regular test. This problem is somewhat similar to the situation where a school has a very strong emphasis on one particular area of chemistry and its ~

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final examination reflects this special emphasis. Several schools also indicated that they used the ACS General Chemistrv standard examination, either alone or in conjuncrion with their other tests, and st, thcse questions were included in the snmple accordingly. The data garherd :n thcse cases are actually overwhelmed by the examination material supplied from the other institutions. T o prepare the table, the number of test items submitted per topic was divided by the totalnumber of test items for the year under study. This gave a percentage value for the particular item under consideration. This was done independentlv for the orieinal1962-3 studv and for the current study of t h e 1974-5 ye;. The table indiiates the relative emphasis of these t o ~ i c for s the two years under consideration and how i t has changed during the interval between the two years. No attempt was made to prepare a tahle where each topic was further broken down into a greater number of subtopics. Several observations are worth noting. One is struck by the great similarity of the data obtained in 1962-3 to the recent data of 1974-5 in many cases, such a s the items under Applied Thermodynamics, Kinetics except for rate constant, Analytical Chemistry except for the new topic of instrumental analysis, and most of the topics included under the broad area of other topics. Secondly, the data on descriptive general and inorganic combined show a decline from 19.4% to 11.4%, lending credence to the accepted idea that descriptive chemistrv has been declining in its extent of coverage within college &emistry. Lastly, ir appears that none of the n e w r topics hasas yet made major inroads into the first year course ar lt,ast as measured hy this approach. It ii possible that they are being discussed or presented as illustrariuns, applications. or sidelights but as of today not as topics upon which one could he tested. This data honefullv will be of some h e l to ~ those Dersons interested in th'e futire of the college chemistry course and those who must do the nlanniue for these courses. Obviously, each reader must reach'his ownconclusions in line with his or her particular situation. Based on a paper presented at the 11th Middle Atlantic Regional Meetine of the American Chemical Societv at the University of Delaware, Newark, Delaware, April 1977. Nechamkin, H. J., J. CHEM. EDUC., 38,255 (1961). 2 Jones, D. E., and Roswell, D. F., J. CHEM. EDUC., 50, 359 (1973). Young, J., J. CHEM. EDUC., 41,477 (1964).

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Volume 55, Number 2, February 1978 1 101