CHEMISTRY, in keeping with our motto "Our students do chemistry as it's done by chemists today," has a well-equipped sequence of laboratory courses that make possible a unique, four-year integrated laboratory experience.
How is the chemistry laboratory program unique?
The first two years of laboratory are devoted to acquiring technical skills and manipulative facility as well as experience in experimental design. The outline of those years below details the projects and the techniques acquired during them.
Project IA: Synthesis of coordination compound that contains a transition metal and halide and organometallic ligands. Techniques: Organizing and keeping a research notebook; using chemical literature to research, design, & complete simple inorganic synthesis. Techniques: weighing and recrystallization.
Project IB: Quantitative analysis of compound from Project IA for % metal, % halide, mole ratio. Techniques: Gravimetric halide and volumetric EDTA metal analysis. Atomic absorption spectroscopy; infrared spectroscopy (optional).
Project IIA: Separation and identification of a mixture of two unknown organic liquids Techniques: Distillation, Gas Chromatography, Proton and Carbon Nuclear Magnetic Resonance Spectroscopy, Infrared Spectroscopy
Project IIB: Identification of an unknown solid organic acid Techniques: Melting Point Determination, Determination of pKa and Equivalent Weight by Acid-Base Titration
Project III: Elucidation of the mechanism of hydrolysis using kinetics of a series of substituted benzoate esters and Hammett Linear Free Energy Relationship analysis.
A: Synthesis, recrystallization, and characterization (by MPt, IR,1H-NMR, and 13C-NMR) of a substituted 4-nitrophenyl benzoate ester - includes a literature search of CAS database using SciFinder.
B: Beer's Law determination of Molar Absorptivity of 4-Nitrophenol in pH 10 buffer using a diode array spectrometers. Application of Beer's Law results to the design of an experimental method for kinetics of hydrolysis of esters.
C: Determination of rate constants for substituted 4-nitrophenyl benzoate esters by UV-Vis spectroscopy. Application of Hammett plot to data set collected by entire class to support mechanism or disprove mechanisms.
Project IV: Preparation of a bifunctional organometallic complex; testing of complex as a catalyst for a condenstation reaction.
A: Brief synthesis of Schiff base ligands using lit search to help design experiment. Separation-purification by flash chromatography with characterization by MPt, IR,1H-NMR, and 13C-NMR.
B: Preparation of coordination complex of ligand; Job Plot to determine optimal mole ratio of ligand to metal ion.
C: Evaluation of Metal-Ligand complex as catalyst of condensation reaction with analysis of results by GC/MS of product mixtures.
Junior and senior chemistry majors enroll in successive semesters in Advanced Laboratory: Chemistry 351, 352, 451, and 452. Each of these laboratory courses meets two afternoons per week for a semester. During each course the student focuses his attention on a single semester-long project. In the total four- semester sequence a student generally collaborates with each member of the department for a semester. During a typical project, the student completes a literature search as the basis for a written project proposal, meets weekly with his collaborating professor to discuss the progress of his work, presents at least one research seminar, and completes a formal technical report of his investigations. Thus, by the time of graduation, each chemistry major has completed four extended projects in the various fields of chemistry. Projects involve advanced synthetic techniques in biochemistry and in organic and inorganic chemistry, chemical analysis and structure determination by instrumental methods, computer acquisition and reduction of data, and instrumental development and evaluation. The levels of projects are adjusted for the background of each student and, over the two-year period of Advanced Laboratory experience, projects are selected to give the student a background as wide as, if not wider than, the conventional laboratories operated at other institutions.
The success of the laboratory program is dependent on three factors: First, the laboratory is carefully controlled: In addition to nominal supervision while he works, the student has a weekly 30 minute "research" conference with the professor in charge of his project. To that conference the student brings a brief written research report that recounts his work of the previous week, evaluates the significance of the work in relation to his overall project, and plans his work for the forthcoming week. His report is examined, his progress is discussed and compared with his previous plan of action, and that plan is reviewed and revised as necessary. Second, the student has received attitudinal and technical preparation from the introductory laboratories. When he enters Advanced Lab, he has used VPC, IR, and NMR as routine tools in pursuing earlier projects. He has synthesized several organic and coordination com- pounds, and has characterized them with the spectral techniques mentioned above; he has repeatedly used both the primary and secondary literature and has written journal-style reports. Most important, he has been induced to think for himself: to find relevant literature, to design experiments, to carry these out (and repeat them if necessary), and to cope with unexpected results. Third, the program works because the projects are tailored to suit the student's needs, interests, abilities, and background, and because the students find the projects interesting. This last point is crucial: there are few problems of motivation when laboratory work closely approximates real chemistry, done as a real chemist would do it, using the most modern techniques.
The program as outlined above is challenging for undergraduates. That it is successful is evidenced by the number and quality of chemistry majors and by the success of recent graduates (over 80% of whom have gone on to graduate or professional school).