Descriptive Chemistry in the General Chemistry Laboratory A Learning Cycle Approach David M. Whisnant Northland College, Ashland, WI 54806 After trying other ways of presenting descriptive inorganic chemistry in our general chemistry course we have, since the 19%-79 ;chool y&r, devoted all o& serond-semester general chemistry lahorator~estn that suhiect. Instead of spending the entire sekester duing different experiments wh~chillustrate the chemistry of various groups and/or elemrnts we have chosen a less-traditional approach suggested by a colleague (I)who is using a similar strategy in an upper level inorganic course. The laboratories are planned to develop and apply several general principles which help rationalize and unify the chemistrv of the elements and their comnounds. The students still do anumber of experiments related'to different elements, and some of the experiments are not that different from the traditional ones except for their purpose-to develop or apply the principles we have chosen. We like this approach because our past requirement of descriptive chemistry has involved quite a hit of memorization on the parts of the students. We hope that the laboratory work, coupled with a set of principles tvine some of the chemistrv " .toeether. will help the students remember more without as much rote memokation heing necessarv. One advantage of using the laboratory to introduce the ~ r i n c i ~ l is e sthat the students can develop these principles ihemshves. For a number of years we have taught withpiaeetian-based learnine.. cvcles . . 3) in one section of our . (2. general chemistry vourse. These laboratory-centered cycles use what has heen termed "guided inquiry" ( 4 ) to help studrnis work out a new roncept on their own with only guidance from the instrurtor. Each cycle consists of three phases.
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fi.'rploratron: Takes familiar concrete experirnres and moves to new concrete artivitie~which help guidestudent
