Orientotion to General Chemistry: An Experimental Approach A design featuring greater student participation was used to begin our course in general chemistry. Student expectations and those of the instructor were shared and compared. Some very basic themes characteristic of science were presented. Viewpoints for qproaching chemistry were presented and stressed. The class was the chemistry department's introductory offering. I t was taken hy 70 students including prospective science majors, premedical students, and s.smaller group seeking only to satisfy the school's science requirement and perhaps their own curiosity. At the first class meeting course goals were discussed. A written handout was used in informing students of class The students were ssked to respond to the question, "What are your goals in taking this course?". They discussed this question in small groups and then reported to the class. A variety of responses were elicited ranging from the satisfaction of requirements to curiosity. I then reported some goals that I had for the clsss. These were hased an the definitions: (1)Chemistry is a human activity and (2) "Chemistry is a body of knowledge, namely all the knowledge called chemical" [HUTCHINSON, E., J. CHEM.EDUC.,44,261 (1967)l. The course goals were to begin to think or act in the manner of a chemist and to acquire some chemical knowledge. To simply seek to learn content by memorization was cleerly identified as insufficient as a mode of operation. Science also was noted to have a history and to chsnge in time. A four-fold model of learning was then presented. One has an experience. One can look to identifv features of the experience. That experien&can then be analyaed. Finally, one can try to generalize knowledge re"sulting from that analysis. The applicability of such a model for learning in a laboratory context or in solving problems was discussed. Our common experience can teach us some sharable knowledge and methods. Less obviously, but still important,, one can use his experience in a chemistry course to identify his perspective of what science is sbaut and where it fits into his value scheme. The second class meeting had a theme of communication. "Fourth quarter, third and eight" was quickly identified to have units. Students were well aware of the differencein uncertainty between measurements an a continuous scale such ss distance on a football field and integral measurements such as downs. Significant figures were then presented as a technique for preserving the meaning in statements of measurements. Trisl calculations of inches to miles and centimeters to meters illustrated the relative convenienceof differentsystems of units. In a. similar fashion, a strong word such as love clearly takes on meaning in context. That oxygen would have different meanings as a gas, element, atom in isolation, or atom in compound, was presented an extension of our knowledge of language. At the third class meeting, students were asked to write their definition of an atom. These were set aside as a. demonstration was performed. Some students saw an orange powder converted to a grey liquid while others rernrted seeing mercuric oxide give mercury. A distinction was then made between observation and interpretation. ~efinitionsof atoms were shared. No student definitions were operational. ~ t t e n t i o nwas returned to the reaction demonstrated. A definition, "elements are simplest suhstmces," was presented, and the students were told that one substance in the demonstration was an element. An explanation of the reaction as representing the combination of the elements fire and earth was not countered succesfully by the class. At this time the students were quite uncomfortable, for their scientificpicture based on authority was being chsllanged. An operational definition, "SIMPLEST = LIGHTEST,'! enabled progress to resume. At the following class meeb ing, Dalton's atom as based on weight relations was developed as a definition of stoms that contained operational elements. Having looked at concepts in a historical manner to help rediscover their experimental basis, the presentation of a modern picture of the atom was the occasion to identify various wsys to approach learning. An historic appreciation, the study of problems of high current relevance, and a look at important broad themes of chemistry hrwe both strengths and weaknesses. Students should recognize that the medium effectsthe message even in learning chemistry and that an effortto look at knowledge one is acquiring in multiple context can be velueble. This is a difficult experiment to eveluate. Student evaluations of the orientation differed widely. A majority of students who rated themselves as well prepared or as poorly prepared for college chemistry were favorable. Those who thought their preprtrstion shout average were about equally divided. A larger number of strongly positive than strongly negative comments were received from each group. I t may be that the group most prepared to operate within the usual course structure showed the greatest resistance to change. I have a subjective, positive evaluation of the orientation. More students seemed to get off to a good start in chemistry. I received more feedback from students. In response to the success of the orientation, subsequent classes were sometimes designed to permit greater student participation. While the sample is small, it is intriguing that compared to the previous elas9 which I taught more traditionally, more than twice as many students from this class majoring in science. The greater student involvement and instrootor's involvement in the course are was rewarding.
JAMES N. LOWE OF THE SOUTH T ~ lUNIVERSITY r SEWANEE, TBNNIISGEI 37375
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Journnl of Chemical Education
