Models were prepared by 3D printing that can be used to demonstrate the operations required for the study of molecular symmetry. The models were designed to emphasize the order and locations of rotation axes and to clearly illustrate the more abstract reflection and improper rotation axes. The models were well-received by students in a course on molecular structure, who generally felt that their understanding of the topic was enhanced by using the models.

The use of silver in commercial products has proliferated in recent years owing to its antibacterial properties. Food containers impregnated with micro-sized silver promise long food life, but there is some concern because silver can leach out of the plastic and into the stored food. This laboratory experiment gives students the opportunity to design their own study to measure the leached silver via graphite furnace atomic absorption spectrophotometry. In this experiment, students stored deionized water, tap water, and acetic acid in two styles of silver food containers for a week. The less expensive version of the food container consistently had higher levels of leached silver. The acetic acid samples and microwaved samples also had higher silver levels. Students gained experience with sample design, chemical analysis, and data analysis.

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A Microsoft Excel workbook is described that can be used to perform group theory calculations using character tables for 50 chemically significant point groups. The workbook will reduce arbitrary representations, calculate direct products, and identify erroneous representations. In addition, the character tables can be projected for use in the classroom or copied to a word-processor for publication.

A method of animating two-dimensional line graphs for simulated real-time display of data during lectures is presented. This quick method uses the Custom Animation feature of Microsoft PowerPoint software. It is suitable for animation of voltammograms, chromatograms, heating curves, reaction coordinates, and other time-dependent data.

A method is presented for displaying images and graphs of spectra on a single screen in the classroom. This demonstration can be used in discussions of atomic line spectra, absorbance spectroscopy, and solid-state bonding. The simultaneous display of both forms of the spectra helps students to make connections between the qualitative, visual spectra and quantitative, graphical representations.

Mercury is a known neurotoxin that is particularly harmful to children and unborn fetuses. Consumption of contaminated fish is one major route of mercury exposure. This laboratory experiment gives students an opportunity to measure mercury concentrations in store-bought seafood and compare the results to suggested exposure limits. The U.S. Environmental Protection Agency (EPA) recommended method for determination of mercury concentrations is cold-vapor atomic spectroscopy. We propose a method of adapting an existing flame atomic absorbance spectrometer for this technique with little additional cost, thus allowing students to learn about this important technique. Students measured mercury concentrations in swordfish and tuna purchased at a local supermarket. Mercury levels in both fish were within the range found by the U.S. Food and Drug Administration (FDA). Students gained experience with sample digestion, cold-vapor analysis, and data analysis.

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