Laboratory Modules from Dr. Judith Halstead Department of Chemistry Skidmore College Saratoga Springs, NY 12866

The concepts of light and color transcend the boundaries of art, chemistry, biology, and physics, and influence our day to day lives in countless ways. In this module the concepts of light and color are examined, both qualitatively and quantitatively, and the basic science behind some everyday observations is explored. Topics investigated include the use of diffraction gratings, the line spectra of atoms, determination of the wavelength of a Helium-Neon laser, flame spectra, the use of Beer's Law, the absorption spectrum of colored dyes, and additive, subtractive, and complementary colors.

The lab correlates well with topics studied in the first semester of typical general chemistry courses. It is also appropriate for liberal arts chemistry courses. The module contains 10 parts and requires two three-hour laboratory periods for completion. The last section of the module is a self-designed team investigation.

†Assistant Professor of Chemistry, Skidmore College: author to which correspondence should be addressed.

As a result of water's unique physical properties, the evolution and maintenance of life on this planet depends heavily on the presence of appropriately pure water. Human beings can survive extended periods of time with no food but only a few days without water.

In this module students test water samples from local lakes and/or water supplies. Tests include conductivity, dissolved oxygen, pH, alkalinity, hardness, and turbidity. The module includes information on sampling techniques and the storage of water samples. It also includes a thorough discussion of the chemistry behind the methods used. Sample data is given in the instructor's notes.

The module is appropriate for general chemistry, liberal arts chemistry, environmental chemistry, or analytical chemistry laboratories. The lab experiments may be completed in two three-hour labs if students divide up the more lengthy tests and pool their data. Plenty of material is included in the module to challenge the better prepared students; this material can be skipped over, and questions related to it may be omitted, in lower-level chemistry laboratory courses.

^†Assistant Professor of Chemistry, Skidmore College: author to which correspondence should be addressed.

Author Table

General Chemistry Organic Chemistry

Environmental Chemistry Liberal Arts Chemistry

Analytical Chemistry Upper Level Chemistry

Contact Professor Judith Halstead with feedback on her lab modules at halstead@scott.skidmore.edu