Graphics:

• Jerrold J. Jacobsen, University of Wisconsin - Madison, Madison, WI 53706

Text:

• Jerrold J. Jacobsen
• Kelly Houston Jetzer, University of Wisconsin - Madison, Madison, WI 53706
• David Phillips, Wabash College, Crawfordsville, IN 47933

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© 1997 Division of Chemical Education, Inc., American Chemical Society. All rights reserved.