Spectroscopy: An lntroduction for Talented High School
Elalne S. Magyar and James G. Magyar Rhode Island College, Providence, RI 02908 We are involved in a summer program that is designed to offer enrichment in math and sciences to outstanding students who have demonstrated interest and ability in these fields.' This four-week program, The Governor's Summer Program in Science and Mathematics, is funded by the state of Rhode Island through the Office of Higher Education and is free of charge t o the students who participate. Each student participates in two different two-hour cmmes: chemist~ or mathematics in the morning and physics or biology . . .. in the afternoon.2 In this paper we shall describe the chemistry program that we have developed over the past several years. Our topic, Spectroscopy in Chemistry, affords the students the opportunity to use a variety of instruments that they would otherwise not personally encounter until quite far along in a colleee chemistry curriculum. We chose spectroscopv as the main topic for-this program because students are bakicularly intrigued by the opportunity to use modern instruments. Since the major goal of this program is to encourage these talented students to pursue careers in science, i t is valuable for them to see how chemists actually use instrumentation to solve problems. At the same time, we want to increase their understanding of chemistry. Through the various spectroscopy experiments, the students learn important laboratory technioues and have an o ~ ~ o r t u n ito t vreview or to see for the fir; time the related theory andcalculations. l'herlassconsists of 18studentiwhr, havecompleted their sophomore or junior year of high school. The majority have had one sear ot' high schod cbrmisto. An essential element of our program is to provide the students with some laboratory experience in each session. Typically, we spend 30-45 minutes of the oeriod describine the nhvsical . - and chemical phenomena to be investigated or discussing the results of their experiments. All graphing, interpretation of results, and problem sets are done in the lab. There is no homework, although resource materials are available to those who wish todo extra reading in any area, and often the students return to class with their graphing completed. Table 1summarizes the program, which is described in more detail below.
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First Week: Color and Visible Spectroscopy The first week is devoted t o color and visible spectroscopy. After a brief neriod of social introduction and adiscussion of laboratory safety and the use of a laboratory notebook, the students are assigned a partner for the first experiment (partners are rotated during the first three weeks so that all the students get to know each other). Each team selects one of nine different colored solutions. The solutions represent a wide variety of shades and colors and contain such compounds as copper sulfate, nickel chloride, methyl orange, cobalt chloride, and potassium permanganate. Each group is 'See Wonell, J. H. J. Chem. Educ. 1987, 64, 612 tor a different approach. A parallel program at Providence College offers a second group of students courses in biology, computer science, oceanography, and mathematics. Smith S. introduction to IR and NMR Spectroscopy; COMPress: Wentworth, NH; 1980.
Table 1. Outllne of Toplcr and Experiments Week 1: Color and Visible SpecWoscopy 1. Colored 601ut10n~-0b8e~ationand spectrum 2. Plotting of data 3. QuamitativeappllCatlonS 4. Chemi-1 origin of wior Wtraviolet Spectroscopy. FIUOrescenCW,andChernilurninescence Preparation of solutions Recordin0 and anaivsls of UV soectra Fl~orescenceand phosphorescence Chemllumlnescence
Week 2:
1. 2. 3. 4.
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Week 3: Infrared and NwIear Magnetic Resonance Specfmswpy 1. Analysis of IR spectra 2. Spectra of min films 3. Analysis d NMR specha 4. NMR unknown
Week 4: Individual PmlectJ 1-4. One or two projects chosen from the llsf (Table 2) then asked t o describe the color of its solution as precisely as nossible. which serves as an introduction to the importance bf caref"l observation and reporting. These reportsiead to a discussion of the relationship between light absorption and color, color absorbed vs. color observed (a handout is provided), etc. The students spend the remainder of the period using Spectronic 20 spec;rol,hotometers to measure
