Describes a technique that can be used to develop accuracy, precision, and a neat laboratory approach in the student. The technique can also be used to demonstrate the stoichiometry of a reaction. (GS)

Described is a student preparation of YBa2Cu3O8-x, a classroom demonstration of its superconductivity, and an analytical chemistry experiment dealing with the oxidation state of copper in the material. (RH)

Presents a laboratory exercise designed to introduce graphical extrapolation. Major advantages of the method are in its simplicity and speed. The only measuring devices are a centimeter ruler and a micrometer caliper to check wall thickness. (JN)

Describes science activities which have been successful with nonscience majors. Each activity requires students to make observations, record the data gathered, interpret data, and prepare a written report. Subject areas include motion of stars, sunspots, lunar orbits, sunset points, meteor showers, and sun shadows. (JN)

Provides procedures for a simple laboratory activity on exponential growth and its characteristic doubling time. The equipment needed consists of a large plastic bucket, an eyedropper, a stopwatch, an assortment of containers and graduated cylinders, and a supply of water. (JN)

Describes in detail the laboratory procedure for studying the process of amitosis in the vegetative cells of Nitella axillaris. (BR)

Heavily ionizing charged particles produce radiation damage tracks in a wide variety of insulating materials. The experimental properties of these tracks and track recorders are described. The mechanisms by which the tracks are produced are discussed. (Author/KR)

Mathematically analyzes the polarization of rainbows, a phenomenon which can be demonstrated in a laboratory simulation using polaroid sheets, perspex discs, and a white light source. (MLH)

Electrets, the electrical counterparts of magnets, are polarized dielectrics that are permanent on a scale of months. Describes procedures for making electrets out of plastic sheets like Mylar, for testing them and measuring their pole strengths, and for establishing necessary and sufficient demonstrations that they are not simply surface charged.…

Explains magneto-optical effects and describes techniques which may be used, in conjunction with certain materials, to reveal domain structures. In addition, simple experiments are described which enable domains to be observed under various conditions of applied fields. (Author/GA)

Describes a college level exercise in physics for measuring the earth's resistivity. (SL)

Provided is a flow chart for the separation and purification of major, minor, and accessory minerals from granitic rocks. With careful use of heavy liquids, and a Franz Isodynamic Magnetic Separator, it is possible to obtain mineral concentrates with a purity of 95 percent or better. (Author/RH)

Described is an experiment to investigate the plasticizer content in polyvinyl chloride (PVC) products. The experiment is designed for college students using an instrumental analysis laboratory. (RH)

Describes a laboratory study in which students evaluate, in ecological terms, different landscapes representing ecosystems under varying degrees of human domination. Also discusses the context within which the study is arranged. (JN)

Presents a class exercise designed to find out how well students understand the nature and consequences of the mass action law and Le Chatelier's principle as applied to chemical equilibria. The exercise relates to a practical situation and provides simple relations for maximizing equilibrium quantities not found in standard textbooks. (JN)