A simple demonstration is described for introducing metric system prefixes and conversion between different units. The width of the classroom is defined as an arbitrarily standard of length ("room") and measured using a paper streamer. By cutting this into ten equal pieces, a deciroom measure is obtained. Centiroom and milliroom pieces are obtained in a similar manner. Conversion between this system of units and inches illustrates unit conversion calculations. This demonstration naturally leads to discussion of principles of experimental design, precision, and accuracy. While initially designed for use in large lecture halls, this demonstration has also been used successfully in classes with as few as 20 students.
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Citation
Earley, Clarke W. J. Chem. Educ.1999 76 1215.
Keywords
Chemical Education Research; Introductory / High School Chemistry; Demonstrations; Teaching/Learning Theory/Practice
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