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CHEMICAL EDUCATION
A - U S * A Report from the Physical Chemistry Examination Committee on the 1972-1973 Tests
During the past several years, many authors have commented that the undergraduate curriculum is a rapidly changing and sometimes amorphous area. This effect has been bmught about primarily by the attempts of chemical educators to include many of the new developments of science in the typical undergraduate courses. Probably the most dramatic change has been the increasing emphasis on the theoretical aspects of the foundations of chemistry. Naturally this trend has influenced the content of the hasic undergraduate physical chemistry course. Many specific areas such as statistical mechanics, quantum mechanics, spectroscopy, and kinetic theory which were previously given only an introductory or brief treatment, are now an integral part of the basic physical chemistry course. Consequently, after the publication of the 1969 form of the ACS Physical Chemistry examination, the Physical Chemistry Examination Subcommittee initiated an investigation into the changing curriculum of the undergraduate physical chemistry course. It was the initial opinion of the committee that the standard exam would best reflect the current trends if it were reorganized into several separate sections, such as Thermodynamics, Kinetics, Quantum Chemistry and Spectroscopy. A short questionnaire covering the proposed format of the new exam was designed and sent to approximately 1500 four-year institutions in the United States. The results of this questionnaire and their application to the design and construction of the exams published in the 1972-73 academic year are presented in this paper. Results ol the 1970 Physical Chemistry Questionnaire A total of nearly 1100 schools responded (73901, of which 880 indicated that physical chemistry was offered a t their institution. These 880 schools formed the basis for the analysis of the questionnaire. One of the main objectives of the questionnaire was to determine if the separation of the exam into sections would he suitable to the current and future user of the exam. Approximately 40% of the schools that responded indicated that they used the ACS exams in physical chemistry. In contrast, 66% of the schools responded that they would use an exam that was divided into limited sections. Another 11% indicated that they probably would use an exam divided into sections depending on the coverage. The favorable response to the idea of dividing the exam into several sections convinced the committee to pursue this concept in the development of thenew exam. A second question which the committee sought to answer dealt with the appropriate division of the topics in physical chemistry. In order to make this decision in the best interest of the users of the exam, the questionnaire specifically requested information regarding; (1) the type of course sequence offered, (2) the main topics covered, and (3) the order of the presentation of the material. The results of the survey are shown in Tables 1 and 2. The Physical Chemistry courses offered by the schools in the survey consisted mostly of two-semester (67%) and three-quarter sequences (16%). In addition, 11% of the schools indicated a three-semester course sequence offering. Of the schwls that have a two-semester sequence 66% indicated a six-lecture, two-lab credit course while 54% of the schools that have a three-quarter sequence indicated a nine-lecture, three-lab credit course. Of the schools that have a three-semester sequence 19% indicated a nine-lecture, two-lab credit course, 11% indicated a nine-lecture, three-lab credit course and 9% indicated an eight-lecture, two-lab credit course. Anticipated changes in course credit and sequence were reported to he minimal; only 37 of the schools (approximately 5%) indicated a possible change from their present course offering. No definite pattern emerged, although most of the changes (27 schools) were from a two-semester to a three-semester sequence.
Table 1. Course Seauence
'A blank indicates the reapow was less than 1.0%. The schools were also requested to indicate the semester (or quarter) in which the main topics were taught. The results are summarized in Tahle 2. Mast schools reported teaching subject matter in thermodynamics, kinetic theory, and chemical kinetics. Three quarters or more of the schools were teaching statistical thermodynamies, electrochemistry, quantum chemistry, and spectroscopy while approximately one half of the schools indicated that surface phenomena and solid state chemistry were covered. Other significant topics included: phase topics (11% of the schools); solutians (9%), molecular structure (8901, and nuclear chemistry or atomic structure (7%). Approximately 10% of the schools indicated an anticipated change in subject matter emphasis. It is interesting to note that only a very small proportion of the schools (0.5%) have included biochemistry or biological subject matter in the physical chemistry sequence. Division of Physical Chemislry Exam While there did not emerge a uniform opinion regarding the main topics covered in the course, it is obvious from a brief study of Tahle 2 that thermodynamics is a major part of all physical chemistry courses taught in the United States. It, therefore, seemed reasonable to designate one of the divisions as "Thermodynamics and Related Topics" which would include the laws and applications of thermodynamics, electrochemistry, solutions, phase changes, and gas laws. The second major division was ehosen to consist of "Quantum Chemistry, Spectroscopy, and Related topics" which would include basic quantum mechanics, atomic and molecular structure, spectroscopy, and statistical mechanics. The third division was designated as "Kinetics and Dynamic Phenomena" which would include chemical kinetics, kinetic theory of gases, solution conductance, electrophoresis, viscosity and other dynamic processes. The division follows the suggestion of the Hammond Curriculum, parallelling the areas referred to there as energetics, structure, and dynamics. Design and Construction of the 1972-73 Exam A subchairman was selected for each of the three major divisions. Questions for each division were solicited from the appraximately 400 professors who indicated on the questionnaire that they were willing to assist in the preparation of the new exams. From these questions two distinct 45 question exams were formulated for each division and pre-tested at a representative crosssection of the schools responding to the questionnaire. For the final version of the exam in each division considerable effort was expended in selecting questions which had received favorable statistical analysis, i.e., the question was neither too hard nor tao easy, yet discriminated between the poor and the good student. Occasionally a question was included an the final version which did not rank favorably in the statistical analysis. These decisions were made because the committee felt the material covered in the question was fundamentally important, adequately formulated, and a replacement was not available. Volume 51. Number 7. July 1974
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Table 2.
TOPIC (Total number of schools reswnding to this question) Th-odynamies
Main Topics and Semester (or Quarter) in Which Taught
&hook R e w n d i n g t o Question Who Teach thi. T,,ic NO.of % of Schools Sehoola
832 829
1
Semester of Quarter in Which Subject is Taught' Taught in two 3 4 four or more terms
Total
2
1W 99.6
683 82.3%
Statistical thermodynamics
Kinetic theory Chemical kinetics Electrochemistry surface phenomena Quantum chemistry Speetmscopy Solid state chemistry 'First line la number of schwla in
Table 3. Areas Covered in Thermodynamics Sub-Test First Law-Energy conservation, heat, work, state function, application of thermochemistry, heat capacities ( E , H,Cp, 13.3%
11.
c. n.,, --, rri,
Second Law-Entropy, Statistical interpretations, heat transfer, adiabatic proce-, spontaneity, entropy changes for system and surrounding.. 8.9% 111. Third Law-Absolute = e m of temperature, entmpy caleu1ations from heat capacities, statistical considerations. 22.2% IV. Combination of first and second laws-the Gibbs Free Energy (GI; the Helmholtz Free Energy ( A ) ; Thermodynamic relationshiw-Maxwell equations. 13.3% V. Conditions for Establishing Equilibrium, AG, AA, AGO = - R T In K,,, chemical potential (pi) 6.7% VI. Electrochemical Cell. and Electmlyte Solution-EMF Calculations, Nernst equation, Debye-Huckel Theory. 2.2% VII. Phase Equilibria. activity coefficients, Henry's Law, 6 . 7 % VIII. Solutions-activity, Rsoulti Law, ideal and non-ideal behavior. 6.7% IX. properties of cam-ideal and real equations of state.
Table 4. Areas Covered in Quantum Chemistry Sub-Test and principle. in a box. rieid mtro. hirmonic o.cill.tor 11.1% 111. Atomic Structure-hydm~n atom, energy levels 15.6% IV. Molecular Structu-MO theory, VSEPR, moleeulsr pmperties, quantum mechanical techniques 17.8% V. Spectrmcopy-vibration and rotation, nmr, microwave, isotope eff& 13.3% VI. Statistical M e e h a n i H i a t r i b u t i o n in enero. levels. classical and quantum effects 8.9% VII. Miscellaneous-solid state. ~hotochemistry 20.0% 13.3% ..
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Journal of Chemical Education
Basic Quantum Meehanies-wstulstes
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Table 5. Areas Covered in Chemical Dvnamics Sub-test 22.2% 6.7% 11.1% 15.6% 24.4% 4.4%
In each of the divisions a list of important concepts was formulated which categorizes the questions according to subject matter. The concepts for each of the three divisions are shown in Table 3, 4, and 5. For each section the approximate percentage of the questions on the final form of the exam representing the area is shown on the left hand side of the Table. The sections shown in the three tables were formulated according t o (1) the results of the questionnaire, (2) to the table of contents of the major text hooks listed by the respondents to the questionnaire, and to ( 3 ) the contents of the questions received from the collaborating professors. There are several areas which are not listed, e.g., nuclear chemistry and solid state phenomena, but the committee is confident that the material found in Tables 3, 4, and 5 is a n accurate representation of the typical coverage found in a physical chemistry course in the United States. In each of the sub-tests the questions are divided into two parts. Part I consists of 30 questions which require a n absolute minimum of calculations to determine the correct response and in some instances are mere reformulations of important laws or principles. A student with a reasonable knowledge of physical chemistry should be able to determine the correct answer by a process of elimination if a numerical answer is needed. Part I1 consists of 15 questions which are more complicated and are designed to test the student's ability to employ the principles of physical chemistry to solve problems. Some questions require the application of two principles for proper solution. Based on the student's performance in these two divisions it should be possible for the inter-
I.
11. Quantum Mechanical Models-oartick
8.9% 6.7%
I. Kinetie Theory of Gases 11. Vi-ity 111. Solution Conduetanee IV. Theories of Chemical Kinetics V. Rate Laws VI. Temperaturn Dependence of Rates VII. Solution Kineties VIII. Miscellaneous-electrophhhii, photochemistry
ested professor to discern the level of achievement of the student in both fundamentals and application of physical chemistry. After all three of the sub-tests were published a consolidated 60 question test was assembled from the three sub-tests. The coverage is 26, 16, and 18 questions in the areas of Thermodynamics, Quantum Chemistry, and Dynamics, respectively. This exam could he used a t the end of the year or as a test for entering graduate students.
P. Calvin Maybury, Chairman University of South Florida Thermodynamics Harry P. Hopkins, Jr. Georgia State University Quantum Chemistry Lowell H. Hall Eastern Nazarene College Kinetics Percy Warrick Westminister College
