Introduces a bubble-making method for discussion about surface tension and thin film interference. Provides some pictures and list of materials for the apparatus. (YP)

Examines the usefulness of cyclic voltammetry to the determination of a complex compound's stoichiometry. Discusses the experimental design, laboratory equipment, and results. (CW)

Resistance probes for the laboratory can be divided into two main categories: (1) those involving direct use of resistance; and (2) those involving an indirect use of resistance. Described are several applications of both types related to chemistry and physics. (RH)

Described are three chemistry demonstrations designed to be used with overhead projectors. One activity suggests an activity for determining unknown liquids. The second activity describes a plastic spot plate for overhead demonstrations. Also described is a demonstration to show pH of selected chemicals. (RH)

Presents excerpts of a survey on the instrument status in chemistry departments and the perceived needs of those departments for new instruments. Responses are based on data from 32 chemistry departments at major research institutions, 71 departments at smaller schools, and 13 chemical engineering departments. (JN)

Introduces a procedure for a whole class of experiments which require very simple and inexpensive equipment and which illustrate one of the basic problems of chemical reaction engineering. The reactions are designed to allow development of a kinetic rate equation from laboratory data. (JM)

Described is a method of converting vacuum-tube operated Heath analog computers (model ES-201) to linear integrated-circuits. (SL)

Reviews the historical development of physical science teaching at Winchester College with emphases upon practical problems encountered in the early introduction of science curricula to the school system. (CC)

Discusses the use of a simple apparatus to measure contact angles between a liquid drop and a solid surface which are determining factors of wettability. Included are examples of applying this technique to various experimental situations. (CC)

Describes the application of an inexpensive relaxation oscillator circuit which uses a thermistor or a cadmium-sulfide photocell to affect the rate of an audio pulse output. It is especially well suited for qualitative and quantitative measurement of heat or light in classroom situations because of its clearly audible output. (Author/JR)

Discusses the use of a modified electron spin resonance apparatus to demonstrate some features of the expression for the transition probability per second between two energy levels. Applications to the third year laboratory program are suggested. (CC)

Describes a simplified diffraction experiment offered in a workshop with the purpose of illustrating to high school students the relation of science to society. The radii determined for cigarette smoke particles range from 0.2 to 0.5 micrometer in this experiment. Included is a description of the diffraction theory. (CC)

Discusses an experiment on the conservation of momentum and Q-values for elastic and inelastic collisions with frictional energy dissipation taken into account. Indicates that the apparatus is readily fabricated from easily available materials. (CC)