Presents an outline of group separations for a nonhydrogen sulfide analytical scheme applicable to all metallic elements (Bromide scheme). Also presents another outline of an abbreviated and modified version (Iodide scheme) designed for emphasis on nutritionally important metals, with special attention to 10 cations. (JM)

Describes an undergraduate laboratory experiment used to illustrate the use of gas chromatography retention indices for the identification of unknown compounds, specifically for the identification of unknown compounds and for the identification of the volatile compounds responsible for the odor of the banana. Procedures, reference data, and sample…

Provides procedures for synthesizing and purifying a vitamin K metabolite (2,3-epoxide) to introduce many of the techniques used in lipid biochemistry. Includes typical results obtained as well as an optional experiment designed to test the purity of the epoxide obtained. (JM)

Background information, list of materials needed, procedures used, and discussion of typical results are provided for an experiment on the thin layer chromatography of chlorophyll pigments. The experiment works well in high school, since the chemicals used are the same as those used in paper chromatography of plant pigments. (JN)

Discusses the properties of surface-conducting glass and the chemical nature of surface-conducting stannic (tin) oxide. Also provides the procedures necessary for the preparation of surface-conducting stannic oxide films on glass substrates. The experiment is suitable for the advanced inorganic chemistry laboratory. (JN)

Outlines steps to generate cell samples for observation and experimentation. The procedures (which use ordinary laboratory equipment) will establish a short-term primary culture of normal mammalian cells. Information on culture vessels and cell division and a list of questions to generate student interest and involvement in the topics are…

Discusses the need for students to develop understanding of science by designing their own laboratory experiments. Lists examples of concepts that can be taught through student-designed biology experiments. Also gives suggestions and guidelines to ensure that laboratory time is manageable and productive. (DH)

Describes how to modify the commercially available and inexpensive Griffin-Worden (Kontes) glass pressure reactors to permit sampling of homogeneous reactions, without changing the relative concentration of species present. All required parts necessary for the modification are commercially available. (JN)

Procedures for recovering silver and cobalt from laboratory wastes (including those resulting from student experiments) are presented. The procedures are generally applicable since only common, inexpensive laboratory reagents are needed. (JN)

Background information, procedures used, and typical results obtained are provided for an experiment in which the stability constants of unstable complexes are determined. (JN)

Suggests that the preparation of 2-bromopentane from 2-pentanol might represent an instructive addition to a published description of pheromone synthesis in that it is economical, extends the synthetic nature of the problem, and amplifies the mechanistic vagaries of the substitution reaction. Theory, procedures used, and safety considerations are…

Provides the rationale for and examples of experiments designed to test the stability of protons and bound neutrons. Also considers the unification question, cosmological implications, current and future detectors, and current status of knowledge on proton decay. (JN)

Describes an experiment designed to introduce physics majors to the triggered oscilloscope. The experiment uses an inexpensive, easily constructed generator which sends pulses down a long coaxial cable, thus providing useful waveforms. (DH)

Suggests using better materials in fire syringes to obtain more effective results during demonstrations which show the elevation in temperature upon a very rapid (adiabatic) compression of air. Also describes an experiment (using ignition temperatures) which introduces students to the use of thermocouples for high temperature measurements. (DH)

Proposes use of two experiments to sample and analyze contaminents in the laboratory. Experiments focus on estimating hydrogen sulfide levels in the general chemistry laboratory during qualitative analysis and determining the concentration of organic vapors associated with organic chemistry laboratories. (JN)