SOLUTIONS FOR COMPLEX SYSTEMS OF CHEMICAL REACTION KINETICS:AN IRREVERSIBLE UNIMOLECULAR REACTION FOLLOWED BY A REVERSIBLE UNIMOLECULAR REACTION,

摘要

This is the third of a series of reports,in each of which a hypothetical reaction system with an idealized type of chemical kinetics is carefully scrutinized. The analytical solutions for the system where chemical A goes to B at a rate K(1) and chemical B is in equilibrium with chemical C with forward and reverse rates K(2) and K(3) respectively are explored for characteristic features which are useful to the kineticist in determining the rate constants from fragmentary experimental data. It is found that B exhibits a maximum whenever K(3) < K(1). This maximum and the time at which it occurs are among the most useful features in determining the rate constants. A critical examination of the pseudostationary state approximation for B as applied to this system is made,and a related approximation to C is introduced. The approximations are found to have a similar range of validity. The time at which C is at an arbitrary percent of its equilibrium concentration is studied. Under certain conditions this time is essentially independent of one or more of the rate constants. (Author)