Student use of a Carbon Hydrogen Nitrogen (CHN) elemental analyzer in the sophomore organic chemistry course is uncommon. Prior to the acquisition of a Perkin Elmer 2400 Series CHN analyzer, Organic Chemistry students at Arizona Western College (AWC) confirmed as best as possible their molecular creations using techniques that are no longer practiced to any great extent in modern labs, e.g. boiling and/or melting temperature range, and mixed melting points. Data from the CHN analyzer, coupled with results from the techniques used above, are now used to determine the purity of compounds made or extracted. In this presentation the author will discuss the use of the CHN analyzer in Organic Chemistry and student answers to quiz and exam questions relevant to CHN data interpretation. The author also will discuss an Environmental Science lab that used the CHN analyzer to determine the C:N ratio as a function of depth of the biomass in a compost pile. Last, the author will discuss future CHN activities involving the comparative nitrogen content in light red kidney beans, black beans, the seeds of native leguminous plants such as mesquite of the surrounding Sonoran Desert, and edamame. The presentation's author gratefully acknowledges the financial support of the NSF (DUE-0310264, Course Curriculum Laboratory Improvement) to purchase the CHN Analyzer.
Back to Chemical Education Session II
Back to The 33rd Northeast Regional Meeting (July 14-17, 2005)