The construction of a diffraction grating spectroscope has been previously reported. A procedure to fit a linear scale to this spectroscope is described (allowing measurement on wavelength of spectral lines without increasing cost of the assembly). Also described are some applications of this modified spectroscope for secondary school laboratory…

Describes a demonstration involving the controlled combustion of a mixture of metals with black and smokeless powder in a small Erlenmeyer flask. Also describes demonstrations using a device that precludes breathing of hazardous vapors during class demonstrations; the device is easy to transport and use in rooms without sinks. (JN)

Describes a simple method for purifying catalase for the study of proteins. Procedures are systematically and diagramatically presented. Also identifies polyacrylamide gel electrophoresis, kinetic studies, and apparent molecular weight determination as possible techniques to be used in studying proteins. (ML)

Presents an experiment which enables weed science students to observe first-hand the process of herbicide leaching in soils. Features of this technique which demonstrate the movement of herbicide within a column of soil are outlined. Diagrams are provided of the apparatus employed in the exercise. (ML)

Presents a classification scheme for identifying sedimentary rocks in introductory geology laboratories. The key consists of an ordered sequence of tests to perform and observations to make which then suggests a rock name or directs the student to additional tests and/or observations. (ML)

Discusses the instructional potential of Chlamydomonas in providing a basis for a range of experimental investigations to illustrate basic biological phenomena. Describes the use of this algae genus in studies of population growth, photosynthesis, and mating behavior. Procedures for laboratory exercises are included. (ML)

Presents a module that focuses on the solvent property of water. Indicates the knowledge items, skills, processes, and attitudes that are developed in the unit. Includes background information as well as student directions for an experiment on solubility. (ML)

Offers two experiments centering on the properties of ice for elementary age students. Provides a listing of needed materials and recommended procedures. Suggestions for helping students are also included. (ML)

Discusses several environmental problems resulting from thermal pollution. Also discusses experiments which help students develop an awareness and understanding of these problems while reinforcing science process skills, problem-solving methods, and independent logical thinking. (JN)

Background information, procedures, and results are presented for experiments on the pyridoxal/metal ion model system. These experiments illustrate catalysis through Schiff's base formation between aldehydes/ketones and primary amines, catalysis by metal ions, and the predictable manner in which metal ions inhibit or catalyze reactions. (JN)

Although indicators are omnipresent tools in aqueous chemistry, they have not been used extensively to assign solvent properties in nonaqueous systems. Therefore, recent research into a system of metal complexes that can be used to assign donor and acceptor numbers to nonaqueous solvents is summarized. Pertinent experiments are also described. (JN)

Reports on a project used in a junior-level laboratory in which students prepare two alcohols, characterize these compounds, and use a shift reagent for structure determination and peak assignment. Background information, materials needed, procedures used, and typical results obtained are included. (JN)

Describes: (1) a FORTH-language, computer-controlled potentiometric titration; (2) coulometric titrations using computer-interfaced potentiometric endpoint detection; (3) interfacing a scanning infrared spectrophotometer to a microcomputer; (4) demonstrations of signal-to-noise enhancement (digital filtering); (5) and an inexpensive Apple…

Gel filtration is a form of liquid chromatography that separates molecules primarily on the basis of their size. Advantages of using this technique, theoretical aspects, and experiments (including procedures used) are discussed. Several questions for students to answer (with answers) are also provided. (JN)

Presents a buffer demonstration which features visualization of the effects of carbon dioxide on pH. Background information, list of materials needed, procedures used, and a discussion of results obtained are included. (JN)