Describes a demonstration experiment designed to estimate the equilibrium constant by comparing the conductivities of acetic and hydrochloric acids. (CC)

Applications of wheels are shown to be an invaluable tool in teaching the processes and technology of science. (DF)

Describes a course based on laboratory use of three skills as a way of teaching a general method of problem solving. (DF)

An experiment in which both Raman-Nath and Bragg diffraction of light by acoustic waves in water are observed in the sound frequency range from 5 to 45 MHz. The apparatus consists of a laser, light detector, rf power source, quartz transducer, and homemade water cell. (Author/DF)

An experiment involving the preservation of mouse kidney cortex and liver tissues is set up to evaluate the relative tonicity of fixatives. (DF)

A laboratory demonstration is suggested for the formation of a-amylase enzyme in halved grains of barley. Data presented in the article provide some information of the pattern of a- and b-amylase activity during germination. (PS)