Explains a scheme for grading student performance which stresses skills, technique, decision making, and notebook entries. Describes grading system and potential pitfalls. (RT)

Chromium(VI) compounds are classified as oxidizers and must be specially packaged and transported for disposal while Cr(III) compounds are considered nonoxidizers. A process which reduces Cr(VI) to Cr(III) by adding sodium metabisulfite followed by neutralization with magnesium hydroxide is explored. (MVL)

Shows that the mutual repulsion that enables a superconductor to levitate a magnet and a magnet to levitate a superconductor can be combined into a single demonstration. Uses an overhead projector, two pellets of "1-2-3" superconductor, Nd-Fe-B magnets, liquid nitrogen, and paraffin. Offers superconductor preparation, hazards, and disposal…

Discusses the flotation method for the determination of the density of solids. Provides the stepwise experimental procedure with typical data tables and graphs. (YP)

Described is a laboratory procedure for teaching seed stratification. Materials, methods, results, and applicability of the experiment are explained. Diagrams showing the percent of total germination as a function of stratification time and the germination rate of stratified seeds are included. (RT)

Presents an overview of coatings along with paint preparation labs. Provides students with information about and methods for preparing a product that is an integral part of daily life. Gives methodology which can be used to prepare oil based and water based paints. (MVL)

Reports that although excitation at 337nm is less than optimal, detection limits in the range 1-100pg/ml were found. Provides a calibration curve and results for seven organic compounds. (MVL)

Describes a photochemistry experiment designed to introduce photochemical techniques and experience free radical chemistry. Selects Nuclear Magnetic Resonance spectroscopy for the analysis. This activity is suggested for use in an upper level undergraduate organic course. (MVL)

Identifies the properties and characteristics of supercritical fluids. Discusses the methodology for supercritical fluid chromatography including flow rate, plate height, column efficiency, viscosity, and other factors. Reviews instruments, column types, and elution conditions. Lists supercritical fluid data for 22 compounds, mostly organic. (MVL)

Presents a high school chemistry lab experiment using tin (II) chloride to explore the concepts of hydrolysis, Le Chatelier's principle, and electrolysis. Presents methodology and the chemistry involved. Offers questions for the students. (MVL)

Describes some reactions for the identification and application of cyanuric acid. Suggests students may find this applied chemistry interesting because of the use of cyanuric acid in swimming pools and diesel engines. Lists three tests for cyanate ion and two tests for cyanuric acid. (MVL)

Describes a course entitled "Biotechnology Laboratory" which introduces a variety of laboratory methods associated with biotechnology. Describes the history, content, and seven experiments of the course. The seven experiments are selected from microbiology and molecular biology, kinetics and fermentation, and downstream…

A study investigated the use of a clinical competency test for foreign medical graduates applying for medical residency. The test, developed by the Educational Commission for Foreign Medical Graduates (ECFMG) consists of integrated clinical encounters with 10 standardized patients, 60 laserdisc pictorials, and analysis of previously completed…

Described is a project where students gain experience in handling large volumes of hazardous materials, process start up and shut down, equipment failures, operational variations, scaling up, equipment cleaning, and run-time scheduling while working in a modern pilot plant. Included are the system design, experimental procedures, and results. (KR)

Describes an activity in which students investigate the effects of selected natural and synthetic substances on the rate of apple browning. Includes background information for the teacher, a list of necessary materials, and student instructions. (KR)