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Milan F. Dubravcic The Untversity of Akron Akron. Ohio 44325
Practical Alternatives to Laboratory in a Basic Chemistry Course Table 1. Laboratory Experlmentsa 1) Measurements: length, volume, m a s , density and temperature 2) Physical Properties: melting and boiling paint, diffusion,mass consswa-
Anv instructor who has ever supervised a laboratory for non-chemistry mnjors and has carefully observed studenu tit work must have ot'ten come to w n c l u s i ~ ~ nlike s these: "This is, indeed, an eye.opening experiment for our students. They are learning a I d of things here which they should remember for a lone time tu come.'l'his should be of tremendous helo in their st;dy of chemistry." We had been guided by similar suhiective imnressions from the oast when introducing, in 197i, our Basic Chemistry courseand decided,.therefor< to add a laboratorv to the 3 hours of lecture per week. While the expectations remained high for a long time, the rising costs of materials and services prompted us soon to question the merits of a lahoratory. This paper describes an attempt to evaluate more objectively the contribution of laboratory experience on the student achievement in an elementary, oneterm chemistry course and suggests some less expensive alternatives.
tion 3) Oxygen: preparation and properties 41, Reactions: eauations. law of definite orooartions . . 51 Actds and Bases inaleators, react ons, titrat ons 6 , Organc versos lnargan c Compo.nas heat resmance, flammab lib, reac~~~~~
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Organic Reactions and Chromatography: phenols, carboxylic acids, esters. aminas, separation of fwd colors 8) Carbohydrates: Molisch. Benedict's and iadine test, hydrolysis 9) Fats and Proteins: solubility, unsaturatian, soap, xanthoproteic and biuret test, nitrogen detection,precipitation ,,., '170 minlwk. 7)
The Course and the Laboratory Basic Chemistry is a ten-week (one quarter) course for non-chemistry majors in the Community and Technical College of The University of Akron. It does not have any science prerequisites, though about one-half of the students have had high school chemistry. The course consisted of 3 hours of lecture and a 3-hour laboratory per week. It was designed to provide a base for other subjects in a number of Associate Degree programs such as criminalistics in the Criminal Justice program, a course on hazardous materials in the Fire Science program, and anatomy and physiology in health allied programs. Because of the diversified student needs, the course had to be kept general and was to cover principles and facts of general ;hemistry plus a brief introduction to organic and biochemistry. While several texts1 have been used alternately, the laboratories settled on nine main topics (Table 1).The experimental procedures were designed bv the facultv and were accomnanied bv auestions which the &dent was expected to answe; in hisher weekly report. With such an ambitious oroeram and the time restrictions imposed by its format, the course was very demanding for the st"dent. In soite of the generallv favorable evaluation hv students, the ins&uctors continued'to he concerned with p;oblems in the course. The maior questions were centered around the usefulness o f t h e iahordtory in view of its demands fim students' t i m e ccm,iderahle scheduling prublems, and the soaring costs -- -
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Our college is located on the main campus of a medium size state university of a decidedly urban character which means high space utilization, tight schedules, restricted funding, relativelv laree classes and a student pooulation that is goaloriented; employed, commuting and bfien of a more mature ngc.
F n m an educational point 01' view, it is considered ( I ) that in underpndt~ntrrhrmistry courses the laboratory experience
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The texts used were: Williams, A. L., Embree, H. D. and Debey, H. J., "General Chemistry," 2nd ed.. Addison-Weslev Publishine Co.. Readine. MA. 1974. Holum, J. R:, "Elements of ~ e n e r aand"~iolb~ical l ~l&ist'r~,"4th ed., John Wiley & Sons, New York, 1975, (first half of text). Sackheim, G. I., and Schultz, R. M., "Chemistry for the Health Seiences," 2nd ed., Maemillan, New York, 1974, (first half of text).
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has the following main objectives: i t reinforces the lecture material. it teaches the exoerimental techniaues. and i t involves the student in the exciting part of science-discovery. However, it is necessary in practice toqualify the above in the light of the duration and the purpose of a particular course. While all three stated objectives would be valid for, e.g., a chemistry major, it appears that in a course like Basic Chemistry the reinforcement of the lecture material is the only one that can he justifiably maintained under the prevailing conditions and with the type of students we have. The commutine and bread earnine student would not be ahle to soend extra time in preparation for and working in a laboratory to learn the techniques and to do research in a field that is definitely not his primary career goal. Once the roie of the laborat&y was specified as supportive to the lecture, it remained to he seen how to utilize effectively the available resources and the scheduled laboratorv time in trying to help the student understand chemistry. m am el^, with the svllahus as laree as a modern science course can have it, and deyq)ite good ef'fort by the reachers and the studmts alikc, it was c
