Tested demonstrations on (a) color development through the formation of subtractive primary dyes and (b) fluidity of gases are presented. (CP)

Ethylene hydrogenation on a platinum catalyst, electrolytically applied to a tube wall, is a good system for the study of the interactions between diffusion and surface reaction in heterogeneous catalysis. Theoretical background, apparatus, procedure, and student performance of this experiment are discussed. (BB)

Presents the concluding article on a checklist for chemistry laboratory safety. (SL)

Presents a procedure for testing cholesterol level in patients. (SL)

Describes a device for converting LED digital displays to large-scale displays. (SL)

Describes a device to detect flooding by broken water apparatus and to properly shut off the apparatus and water flow. (SL)

Describes the modification of a transistor radio to make an audio oscillator. (SL)

Reviews the chemistry of methylmercury, methylmercury poisoning, and its treatment. (SL)

Describes a laboratory experiment to analyze wine for its major components using a standard enological analytical procedure. (Author/GA)

A phase catalyst approach to nucleophilic and electrophilic reactions is proposed. (CP)

Describes two simple, economic timers suitable for measuring time intervals with fractional millisecond resolution in physics experiments. (MLH)

Describes a technique for preparing and conducting biology laboratory examinations with 35-mm slides in lieu of actual laboratory equipment and materials. Major benefits stressed are the saving of time and preparation when utilized with individualized learning programs and make-up examinations. (SL)

Reports the presence and use of known carcinogens in Kentucky colleges, junior colleges, and high schools. Includes a listing of known carcinogens and the synonym names under which each may be labeled. (SL)

Presents an experiment involving the identification of FD&C dyes by visible spectroscopy. (SL)

Describes a recording gas microvolumeter constructed to carry out sensitive studies of the kinetics of photodecomposition of water. (SL)