Using Infrared Spectroscopy for the Curricular Integration of General

University of San Francisco, San Francisco, CA 94117. In the last decades of the 20th ... within college chemistry cumcula one unfortunate vestige of ...
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Using Infrared Spectroscopy for the Curricular lntegration of General and Organic Chemistry Tami I. Spector University of San Francisco, San Francisco, CA 94117 In the last decades of the 20th centurv. ", some of the greatest achievements in science have come as a result of the dissolution of the artificial boundaries among the disciplines of chemistry, biology, and physics. Nevertheless, within college chemistry cumcula one unfortunate vestige of a separatist discipline a .~. ~ r o a can c h be seen in the evolution oimany gener:al chemistry rourses Into ~ntroductory levcl .~hvsic.il c h t m i i t r ~This aooroach to introductorv " chemistry excludes substantive elements of organic and inorganic chemistry. For example, the use of Lewis structures that are central to the manipulations of mechanistic organic chemistry, are not presented in the context of a reaction or mechanism in general chemistry Arecent article entitled "What is Wrong with General Chemistry" stated, "We need a true general chemistry course that integrates [the] organic, inorganic, and physical chemistry and shows how the ~hvsicaltheorv and ~rinciolescan be used to rationalize and explain observations on the properties of substances" ( I ) . At the Universitv of San Francisco (USF). the extensive and innovative use of infrared spectroscopy a s an integral laboratorv techniaue in the first two vears of undereraduate chemistry has been used to narrow the gap between general and organic chemistry. Molecular spectroscopy is a central tool in the life of a chemist. I t allows us to examine the surface characteristics of a material using Electron Spectroscopy for Chemical Analysis (ESCA) or make a detailed examination of the vibrations of a single bond with infrared. The centralitv of soectroscoov alonp with the recent advent of l o w - c o s t ~ o u ~~e r a n s f i r m~nyrared(FTIR) spectrometers has set the stage for introductory students to explore the real world of modern chemistry in a costand time-efficient manner. Students are introduced early A.

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946

Journal of Chemical Education

on in general chemistry to the concept of bond and molecular vibrations and the ready visualization ofthese concepts through molecular models. These essential concepts are relatively rntuiuve and euiy for students to assimilate and we believe chemical educators and students benefit from exploiting this accessible knowledge to its fullest. The Integration of Organic Chemistry into General Chemistry There are ample opportunities for the integration of organic chemistry into the general chemistry curriculnm. At USF discussions of structure and bonding in general chemistry are accented with organic molecules. We then ground this structural introduction to organic chemistry in the general chemistry laboratory by the appropriate use of IR spectroscopy. For example, a n introductory structurelproperty approach to organic polymers is presented in the second semester of general chemistry. Polymers possess tanaible bulk p r o ~ e r t i e sa n d a r e ubiauitons i n our environment,and, therefore, offer a unique opportunity a s a teaching tool. The students' inherent interest in their surroundings, and by extension in polymers, facilitates a n understanding of the relationship between molecular structure and