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)

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)

Outlines advantages of and provides background information, procedures, and typical student data for an experiment determining rate of hydration of p-methyoxyphenylacetylene (III), followed by nuclear magnetic resonance spectroscopy. Reaction rate can be adjusted to meet time framework of a particular laboratory by altering concentration of…

Everyone who teaches physics knows very well that sometimes a simple device or experiment can help to make a concept clear. In this paper, inspired by "The Jumping Pencil" by Martin Gardner, I will discuss a simple demonstration device that can be used to start the study of air pressure.

Reports a consecutive first-order reaction for which the concentrations of reactant, intermediate, and products can be determined simulataneously. This reaction is the epoxidation of 2,5-di-tert-butyl-1,4-benzoquinone (I) by alkaline hydroperoxidation using tert-butyl hydroperoxide and benzyltrimethylammonium hydroxide (Triton B) catalyst.…

Describes an experiment in which the kinetics of dimerization of nitrosamine induced by a flash of light is measured. The experiment can be performed with a commercial ultraviolet-VIS spetrophotometer with easy to make modifications. The experiment demonstrates a flash photolysis system not always available in university chemistry laboratories.…

Describes how to modify the commercially available and inexpensive Griffin-Worden (Kontes) glass pressure reactors to permit sampling of homogeneous reactions, without changing the relative concentration of species present. All required parts necessary for the modification are commercially available. (JN)

Background information, procedures used, and typical results obtained are provided for an experiment in which the stability constants of unstable complexes are determined. (JN)

Provides background information and problems with the formaldehyde clock reaction, including comparisons of experimental clock times reported in the literature and conditions for the reliable use of the formaldehyde clock based on a method discussed. (JN)

Describes and explains some aspects of the motion of a top, the extreme end of which is made round, spinning on surfaces provided with friction. (Author/GA)

The construction and use of a low-cost continuous-flow instrument for measuring the kinetics of fast reaction which include the use of an light emitting diode light source, a photodiode-on-a-chip detector, and a position sensor is demonstrated. The instrument is suitable for the physical chemistry laboratory and could be used to study the kinetics…