Describes a laboratory activity in which polystyrene spheres in two preassembled motifs must be arranged to form a tetrahedral structure. (MLH)

Compares the coulumbic point charge model for hydrogen chloride with the valence bond model. It is not possible to assign either a nonpolar or ionic canonical form of the valence bond model, while the covalent-ionic bond distribution does conform to the point charge model. (JM)

Voltammetry is used as a model for teaching chemical instrumentation to chemistry undergraduates at the National University of Singapore. Lists six criteria used to select a successful teaching model and shows how voltammetry satisfies each criterion. (JN)

Describes a bonding theory which provides a framework for the description of a wide range of substances and provides quantitative information of remarkable accuracy with far less computational effort than that required of other approaches. Includes applications, such as calculation of bond energies of two binary hydrides (methane and diborane).…

Shows how to make close-packed models from balloons and table tennis balls to illustrate structural features of clusters and organometallic cluster-compounds (which are of great interest in the study of chemical reactions). These models provide a very inexpensive and tactile illustration of the organization of matter for concrete operational…

Offers a simple model for estimating vapor concentrations in instructional laboratories. Three methods are described for measuring ventilation rates, and the results of measurements in six laboratories are presented. The model should provide a simple screening tool for evaluating worst-case personal exposures. (JN)

Provides instructions for making, inexpensively from envelopes, two polyhedra that illustrate chemical geometries. The individual steps involved, supported by detailed diagrams, are included. (JN)

Discusses a successfully implemented laboratory experiment that compares the strengths and weaknesses of mechanical and computer models. The computer models used are available from the Quantum Chemistry Program Exchange (QCPE) at a modest price. (JN)

A model of twin octahedrons having a common line which is useful for teaching stereochemistry (especially that of complex ions) can be made easily by using a sealed, empty envelope. The steps necessary to accomplish this task are presented. (JN)

A model of a cube which is necessary for teaching stereochemistry (especially of inorganic compounds) can be made easily, by using a sealed, empty envelope. The steps necessary to accomplish this task are presented. (JN)

A model of a trigonal prism which is useful for teaching stereochemistry (especially of the neodymium enneahydrate ion), can be made easily by using a sealed, empty envelope. The steps necessary to accomplish this task are presented. (JN)

A model of a square antiprism which is necessary for teaching stereochemistry (for example, of the octafluorotantalate ion) can be made easily by using a sealed, empty envelope. The steps necessary to accomplish this task are presented. (JN)

A model of a dodecahedron which is necessary for teaching stereochemistry (for example, that of dodecahedrane) can be made easily by using a sealed, empty envelope. The steps necessary for accomplishing this task are presented. (JN)

Describes a simple and effective method in which students use their hands, arms, and fingers to determine absolute configurations. (JN)

Outlined are two experiments using liquid membranes that illustrate carrier-facilitated transport, where chemical species are ushered across the membrane by selective "carrier" molecules residing in the membrane. The use of liquid membranes as models for studying and describing biological transport mechanisms is explored. (CS)