New Ideas in the Four-Year Chemistry Curriculum' INTEGRATED INTRODUCTORY COURSE IN PHYSICS AND CHEMISTRY"
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EDWARD L. HAENISCH and LEWIS S. SALTER Wabash College, Crawfordsville, Indiana F O R many years Wabash College has required a year of study in biological science, a year of study in physical science, and a year of college-level mathematics for graduation. To meet these requirements separate survey-type courses in the fields of biological and physical science had been offered for non-majors. About a decade ago a biology course which not only was to be the introduction for all those who intended to do further work in either botany or zoology, but also was t o be the course which fulfilled the graduation requirement in biological science for all students, was successfully developed. Spurred on by the success of this course and by objections to terminal survey courses, the faculty recommended that a similar course in physical science be organized. It took several years to locate staff members in chemistry and physics (the only physical sciences offered a t the college) who were willing to abandon the traditional courses in general chemistry and general physics and who also were ready to make the necessary changes which a combined course would entail in the upper level courses. Four years ago the project began and was aided by a grant from the Fund for the Advancement of Education of the Ford Foundation. Textual and laboratory materials were developed as the course was given and have been constantly revised. I n designing the course the following were considered: Neither modern chemistry nor physics can be understood without a knowledge of the other science. Frequently the beginner in chemistry has to take much of the work in atomic structure on faith because he has not b d the proper background in physics. This difficulty can be avoided in a combined course. Furthermore, much repetition usually found in the customary introductory courses is avoided. This particularly occurs with reference t o gas laws, states of matter, atomic structure, and electrochemistry. I n most of the current f i ~ s year t courses in general physics and general chemistry the major emphasis is placed on the accumulation of factual materials and phenomenological formulas needed for advanced
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Far urevious muers in this Svmuosium see J. CHEM.EDUC.. 35, l64ff. (1958). 9 Presented as part of the Symposium on New Ideas in the Four-Year Chemistry Curriculum before the Division of Chemical Eduestion at the 132nd Meeting of the American Chemical Society, New York, September, 1957.
study in these sciences. It is the plethora of this type of learning which accords these courses the reputation of drudgery for non-scientists. Often little attention is paid t o the experimental foundations, to the methodology, or to the theoretical concepts and definitions which form the basis of the physical sciences. Historical aspects, relation of physics and chemistry t o each other and to other sciences, and social problems arising from scientific development are not touched. I n fact, many of these topics are frequently relegated to a course in "physical science" for non-science majors. It is the belief of the Wabash College science faculty that science majors as well as non-science majors should have knowledge of these aspects. It was also the conviction of the science faculty that non-science maj ors can best appreciate the meaning and place of the physical sciences not only by having the conceptual and methodological background but also by being exposed to, and by using, some of the theories and problems which the science major must learn in order to advance in his chosen field. Non-science students should be exposed t o a course "in science" rather than merely one "about science." The students who plan t o continue in humanities or social sciences also ought t o have some actual experience in the collection, and interpretation by mathematical methods, of experimental data. THE NATURE OF MATTER AND ENERGY The course is built around the theme of the nature of matter and energy. A brief introduction is followed by the development of the atomic theory based on a n examination of the weight and vohnne relations in chemical change. Historical aspects such as the demise of the phlogiston theory and the Dalton-Avogadro controversy are included. These studies lead to the use of arithmetical relations as applied t o the "shorthand" of chemistry in its equation&and culminates in the periodic table as conceived by Mendeleev. A sharp transition t o the study of mechanics follows. It begins with motion in one dimension and the difference between average and instantaneous velocities. The necessity for the use of vectors and for the invention of the calculus is made clear in order to formulate exact and far-reaching definitions of velocity and acceleration. Enough mathematics is introduced so that the analytical geometry of the straight line and the JOURNAL OF CHEMICAL EDUCATION
differentiation and integration of polynomials is understood and applied. I h fact, the students do not resist the calculus but rather show great interest in it when they see its close connection with the precise formulation of the concept of instantaneous velocity and of rates of change in general. The concepts of force, mass, momentum, and energy are developed along with the important conservation laws. The first law of thermodynamics is discussed. A study of the states of aggregation of bulk matter follows and permits the combination of the atomic theory and mechanics in the kinetic molecular theory; this can accordingly be presented a t a higher level of rigor and precision than is customary in elementary courses. This presentation permits emphasis on how a useful theoretical model can be satisfactorily developed from a combination of physical and chemical concepts and mathematical principles. A brief treatment of the second law of thermodynamics (in terms of the correlation between entropy and molecular randomness) and its significanceis included. Electricity and magnetism are next developed, as prototypes of field theories. These lay the background for a brief treatment of electromagnetic radiation and the properties of waves. A point has now been reached a t which the modern notions of atomic structure, quantum theory, radioactivity, and nuclear energy can be properly presented. The periodic table is explained in its modern "long" form in terms of the quantum theory restriction on the allowed orbitals of the electrons in the atom. The chemical bond is next examined. This leads t o a treatment of chemical reactions, the conditions involved, the energetics and kinetics of such reactions, and the nature of chemical equilibrium. Finally, oxidation-reduction and its relation to electrochemical processes is studied. As for mechanical details, the course carries four hours of credit per semester--two hours of lecture, one hour of recitation, and one &hour laboratory period each week. It is assumed that a t the end of the year the students have four hours' credit in chemistry and four in physics. The lectures over the course of the year are given jointly be a member of the chemistrv staff and a member of the physics staff who divide the various sections of the material. The recitations and laboratory sections are manned by either chemists or physicists, and these people carry on throughout the year regardless of the topic considered in the classroom and laboratory. Included in the laboratory are many of the standard experiments of chemistry and physics. I n chemistry
VOLUME 35, NO. 5, MAY, 1958
such things as the laws of definite and multiple proportions, determination of formulas, gas laws, measurement of equivalent weight are included. Several of the laboratories are devoted to development of m a t h e matical techniques, such as making and interpreting graphs, measurement of area, etc. A number of laboratory experiments are included where the students are expected, by collecting data and interpreting it, to deduce physical and chemical laws not covered in the classroom. Such experiments include the behavior of pendulums, the speed of chemical reaction, etc. FOUNDATION FOR FURTHER SCIENCE COURSES
A few words on the remainder of the curriculum may be in order. The first semester of sophomore chemistry is a course on inorganic chemistry and introductory qualitative analysis. Much of the descriptive chemistry omitted from the first year course is completed along with a detailed study of equilibrium calculations. Completion of this course gives the student the equivalent of a year's credit in general chemistry. The second semester of the sophomore year is an introductory quantitative analysis course. I n the junior year courses in organic and physical chemistry are taken. The senior year includes a semester of advanced organic chemistry and a semester of advanced analytical chemistry along with certain other options. The sophomore year in physics is called "intermediate physics" and fills inmany of the gaps from the first year course. Oh the whole, student reaction t o the integrated course in physics and chemistry has been good. The students seem pleased to be given a sound explanation of the whys and wherefores of the fundamentals of physics and chemistry without all the jumping around among varied topics which usually takes place in separate beginning courses in the two fields. Encouraged by this response the Wabash faculty is continuing its efforts to improve the course. Finally, it is interesting to note that each staff member regardless of whether he is a physicist or a chemist has to carry his own recitation and laboratory sections throughout the whole academic year without reference t o the material under discussion. This has led to a better knowledge and understanding of both sciences by each teacher and has had far-reaching effects on the mutual relations of the two departments and the content of the upper level courses. Particularly valuable has been the unification of viewpoints on such topics as gas laws, electrochemistry, etc., which were normally treated separately by the physicists and chemists in their own introductory courses.
