A graphite furnace atomic absorption spectrometer (GF-AAS) is being integrated across the college's chemistry curriculum and also in cross-disciplinary courses with the biology department. Specifically, usage of the GF-AAS is being incorporated into new or revised lab experiments in both semesters of general chemistry, and four upper-level chemistry courses: quantitative analysis, the second semester of physical chemistry, the first semester of biochemistry, and instrumental methods. In addition, project faculty are developing laboratory experiments involving GF-AAS usage in a cross-disciplinary ecology lab course, a course on the global environment, and the plant physiology lab course in the biology department. The lab experiments for chemistry and biology courses are being developed with special emphasis on capturing students' interest, and several of these experiments are creating vehicles for learning chemistry content that naturally touch on social justice issues in ethically appropriate ways. Learning and disposition outcomes for each of the laboratory experiments involving GF-AAS usage have been identified and are being assessed. The project has four main goals: 1) to offer real-world application of chemical analysis in student laboratories; 2) to use GF-AAS in new and interesting experiments in upper level chemistry laboratories; 3) to use chemical analysis in teaching disciplines other than chemistry; and 4) to make chemistry fun and interesting, i.e., accessible. These goals are integrated with the learning aims in the chemistry department's plan for assessing its overall commitment to offer a rigorous program that prepares students for future careers in science. The evaluation is analyzing pre- and post-course measurements of students' conceptual understanding through concept inventories in several courses. The evaluation is also longitudinally tracking chemistry majors as they progress through the undergraduate chemistry curriculum, to assess how usage of GF-AAS in many of their courses intensifies student interest in and understanding of techniques involving GF-AAS. The new laboratory experiments are being disseminated through peer-reviewed publications in chemical education and biology education and through cross-postings on NSDL. Research results are being shared through conferences and peer-reviewed journals in science education. The experiments are also being made available through Perkin-Elmer for use by other institutions that use the same instrument or are interested in incorporating usage of the instrument into their curricula.
The goal of this project was to incorporate instrumentation used for measuring chemical elements (an atomic absorption spectrometer (AAS)) into all levels of the chemistry curriculum at Loyola University Maryland. In undergraduate chemistry curriculum, lower level courses focus on basic techniques and students are generally not exposed to instruments used for chemical analysis. While basic techniques are important for students to understand, learn, and use; in working laboratories many chemical measurements are done using instrumentation. At our institution, an AAS instrument was previously used only in an advanced course, typically taken by seniors. By using this instrument in the introductory chemistry sequence students enrolled in the courses learned the real-world application of chemical analysis and received an introduction to atomic spectroscopy. The newly designed sequence of laboratory experiments included the following educational experiments. Determination of Manganese in Steel via UV-Vis Spectrophotometry and Atomic Absorption Spectroscopy - General Chemistry Lab 1 (1st year course). Addition of AAS to laboratory experiment already in place. Determination of Zinc in Human Hair - General Chemistry Lab II (1st year course). Newly designed laboratory with co-learning experience in Ecology, Evolution and Biodiversity (a 1st/2nd year Biology Course). Determination of Calcium and Magnesium - Quantitative Analysis (2nd year course). A newly designed guided inquiry style laboratory experiment that allows students to choose to use the AAS or a titration technique. Atomic Absorption Experiment on Microstates - Physical Chemistry Lab II (3rd year course). This new laboratory experiment was designed to illustrate different microstates of atoms and explain the significance of atomic term symbols. Analysis of Zinc, Lead and Manganese in Human Hair via Atomic Absorption Spectroscopy - Instrumental Methods Lab (4th year course). Students must use both the furnace and the flame on the instrument to gather the data. This is a new experiment for the course. In addition to the chemistry courses listed above - the Plant Physiology course in the Biology department also utilizes the instrument in a laboratory experiment so that student may determine which metals are impacting their plant specimens. In this way students enrolled in the 2 biology courses that utilize the instrument (Ecology & Plant Physiology) are able to use chemistry to answer biological questions - as is often done in working laboratories. In analyzing how the use of the instrument affected student learning we found that in a survey of students in general chemistry significant increases were reported from the students perceptions of chemistry including efforts to use information, understanding of concepts, ability to link math and chemistry, belief that learning chemistry is essential, the importance of laboratory visualization of atoms and molecules. This may not be a direct result of the instrument incorporation - however, it does indicate that further investigation into why this occurred may be useful to fully understand the impact of the instrumentation. One of the key outcomes for this project was that it allowed members of the chemistry department and biology department to consider how the instruction in both departments can complement each other through laboratory experiments. While this is not a unique outcome for this project – it is a new approach for our university which allowed us to challenge ourselves to improve our curriculum. The 2nd key outcome is the consideration of using an instrument to build upon concepts as student progress through the chemistry curriculum. While chemistry curriculum has done this in the past, it was not intentionally planned nor was it explicitly stated to the students and to the faculty teaching the affected courses. This has led us to consider what other ways we can connect the laboratory courses to build on student knowledge and improve our curriculum.
