Presents an analog of radioactive decay that allows the student to grasp the concept of half life and the exponential nature of the decay process. The analog is devised to use small, colored, plastic poker chips or counters. Provides the typical data and a graph which supports the analog. (YP)

Describes a technique which gives an automatic and accurate assessment of photosynthetic oxygen liberation with graphical results available immediately. This program takes readings from an oxygen electrode and a photocell simultaneously. The types of results and unique features of the technique are discussed. (ML)

Describes procedures for two demonstrations: (1) photochemical energy conversion using ferric oxalate actinometry and (2) liquification of gases using Freon 114. Safety precautions are given for both demonstrations, as are procedures and material specifications. (JM)

Describes procedures involved with paper electrophoresis separation of amino acids, gel electrophoresis separation of DNA, and design of an electrophoresis tank. Describes experiments using paper (amino acids) and gel (deoxyribonucleic acid fragments). Provides material lists, procedures, and discussion. (JM)

A general laboratory course should include projects that familiarize college students with the variety of methods available to the researcher. Described are four research projects that address questions about human behavior by means of experimental, observational, survey, and archival research methods. (RM)

Described are different chemistry curricula that use lecture-experiments. Different components are discussed within the lecture-experiment format, such as determinism, memory, note taking, descriptive chemistry, and holistic chemistry. Also discussed are different personalities in chemistry education. (DS)

Described is a diffusion apparatus to be used in an undergraduate physical chemistry laboratory experiment to determine the diffusion coefficients of aqueous solutions of sucrose and potassium dichromate. Included is the principle of the method, apparatus design and description, and experimental procedure. (Author/DS)

Described is a science experiment involving the isolation and study of microorganisms. Bacteria from the mouth are cultured on blood agar culture plates and are then exposed to four different mouthwashes to test their effectiveness. (DS)

Presents an experiment which uses readily available starting materials and inexpensive equipment for synthesis of transition metal carbonyls at 1000 atm and which is intended to give students experience in techniques used in research and industry. Safety precautions are emphasized. (Author/SA)

A three-point linkage system in tomatoes is used to explain concepts of gene mapping, linking and statistical analysis. The system is designed for teaching the effective use of statistics, and the power of genetic analysis from statistical analysis of phenotypic ratios. (Author/SA)

This inexpensive but informative experiment for undergraduate biochemistry students involves isolating phosphatidyl choline from spinach leaves. Emphasis is on introducing students to techniques of lipid extraction, separation of lipids, identification using thin layer chromatography, and identification of fatty acids. Three periods of three hours…

Describes a physics experiment investigating temperature prediction and the relationship between the physical properties of heat units, melting, dissolving, states of matter, and energy loss. Details the experimental setup, which requires hot and cold water, a thermometer, and ice. Notes that the experiment employs a deliberate counter-intuitive…

Presents a procedure for an integrated first year chemistry laboratory class which provides an effective and colorful procedure to develop manipulative skills in synthesis and purification. Uses thin layer chromatography and NMR spectroscopy in the determination. Provides Rf values and representative NMR spectra. (MVL)

Develops an experiment that could be done in two- to three-hour blocks and does not rely on cold room procedures for most of the purification. Describes the materials, methods, and results of the purification of bovine heart lactate dehydrogenase using ammonium sulfate fractionation, dialysis, and separation using affinity chromatography and…

Presents an exercise which was designed to help students read material and follow directions more appropriately when performing laboratory activities. Provides a list of materials, instructions, comments, vocabulary words, and a diagrammatical sketch of an insect. (RT)