Examines mechanisms related to use of N-bromosuccinimide (NBS) for bromination at an allylic position. Also presents derived rate laws for three possible reactions of molecular bromine with an alkene: (1) free radical substitution; (2) free radical addition; and (3) electrophilic addition. (JN)

Kinetic versus thermodynamic control of product formation is discussed in undergraduate textbooks, and journal papers suggest suitable experiments to illustrate this concept. In rationalizing experimental observations, this paper offers a new alternative to that conventionally employed and provides students with an interesting exercise in…

Describes an undergraduate enzyme kinetics experiment which uses bovine erythrocyte carbonic anhydrase, a very stable enzyme commercially available in lyophilized form. Includes background information, reactions involved, procedures used, and the calculation of typical results obtained. (JN)

Possible modes of food deterioration (such as microbial decay, nonenzymatic browning, senescence, lipid oxidation) are reviewed. A basic mathematical approach to the kinetics of food deterioration, kinetic approach to accelerating shelf-life deterioration, and shelf-life predictions are discussed. (JN)

Background information, procedures, and typical results are provided for an experiment on the decomposition of murexide in acid solution. The experiment, suitable for advanced courses, can be easily performed in a 6-hour laboratory period. (JN)

Describes the theory, apparatus, and procedure for an experiment that measures the bimolecular quenching constant for the deactivation of an excited ruthenium ion complex using dissolved oxygen. (MLH)

Describes an experiment in which the reaction rate and equilibrium constant are obtained for the fumarase-catalyzed interconversion of fumaric acid and L-malic acid. (MLH)

Comparison of kinetic data indicated that spline functions were more effective than polynomials for modeling the data. (GW)

Short articles on the kinetics of the hydrogen peroxide-iodide ion reaction, simulation of fluidization catalysis, the use of Newman projection diagrams to represent steric relationships in organic chemistry, the use of synthetic substrates for proteolytic enzyme reactions, and two simple clock reactions"--hydrolysis of halogenoalkanes and…

Recognizes that physics, like other sciences, deals with information in the form of sense impressions. Concepts of mass length and time are not sensory experiences and should substitute instead the terms of force, displacement and time for better understanding. (PS)

Short articles describing the construction of a self-testing device for learning ionic formulae, problems with standard'' experiments in crystallizing sulfur, preparative details for a cold-setting adhesive and vermillion dye, and providing data related to the industrial manufacture of sulphuric acid. (AL)

Short articles describe a method of introducing the study of simple harmonic motion, and suggest models that are analogues for impedence matching, electrical transformers, and birefringent crystals. (AL)