Enzymes are nature's catalysts, mediating chemical processes in living systems. The study of enzyme function and mechanism includes defining the maximum catalytic rate and affinity for substrate/s (among other factors), referred to as enzyme kinetics. Enzyme kinetics is a staple of biochemistry curricula and other disciplines, from molecular and…

An introductory guide to deducing the mechanism of chemical reactions is presented. Following a typical workflow for probing reaction mechanism, the guide introduces a wide range of kinetic and mechanistic tools. In addition to serving as a broad introduction to mechanistic analysis for students and researchers, the guide has also been used by…

It is difficult to know what to do with meaning. Some kinesiologists, particularly those in the humanities, would argue that it should be given due attention--perhaps even priority attention. Others would argue that meaning is unimportant or simply impossible to study in any objective way. This conundrum can be solved by adopting a new research…

Describes a simple redox reaction that occurs between potassium permanganate and oxalic acid that can be used to prepare an interesting disappearing ink for demonstrating kinetics for introductory chemistry. Discusses laboratory procedures and factors that influence disappearance times. (CW)

Conveys an appreciation of enzyme kinetic analysis by using a practical and intuitive approach. Discusses enzyme assays, kinetic models and rate laws, the kinetic constants (V, velocity, and Km, Michaels constant), evaluation of V and Km from experimental data, and enzyme inhibition. (CW)

Defines the rate-controlling step in contrast to the terms rate determining and rate limiting. Discusses the usefulness of this concept in describing kinetic isotope effects, consecutive reactions, chain reactions, and enzyme-catalyzed reactions. (CW)

Describes a kinetic and mechanistic investigation of ascorbic acid by a substitution-inert complex in acidic medium suitable for the undergraduate level. Discusses obtaining the second order rate constant for the rate determining step at a given temperature and comparison with the value predicted on the basis of the Marcus cross-relation. (CW)

Discusses the mechanism and the change of pH during the reaction. Notes that a dramatic rise in pH occurs when the reaction nears completion. Evaluates theories by other authors. (MVL)

Almost all experimental investigations on concepts of time (T), distance (D) and velocity (V) since 1946 have been based on the Piagetian theory. However, there are several controversial points in Piaget's investigations. In the experiment described in this paper, developmental changes of concepts concerning relation of T, D, and V were examined…

Considers two types of laser applications in kinetics. Explores short laser pulses to prepare a reactant in a known state and a continuous laser as a probe to monitor specific species in a reaction. Describes how lasers work and provides several examples of kinetic reactions. (ML)

Describes three case studies of the use of the Learning in Science Project (Energy) in New Zealand. Themes discussed include systems undergoing change, defining initial and final conditions, energy as a nonmaterial factor of change, forms of energy and conservation of energy. Mentions other issues and research. (CW)