Nitrogen pentoxide decomposition kinetics

The unit of the velocity constant k is sec-1. Many reactions follow first order kinetics or pseudo-first order kinetics over certain ranges of experimental conditions. Examples are the cracking of butane, many pyrolysis reactions, the decomposition of nitrogen pentoxide (N205), and the radioactive disintegration of unstable nuclei. Instead of the velocity constant, a quantity referred to as the half-life t1/2 is often used. The half-life is the time required for the concentration of the reactant to drop to one-half of its initial value. Substitution of the appropriate numerical values into Equation 3-33 gives... 

The question immediately arises as to how far this independence of collision will continue as the pressure of nitrogen pentoxide is indefinitely decreased. The matter is of great importance for checking theories of chemical kinetics and accordingly many other investigators undertook the study of the decomposition of nitrogen pentoxide at very low pressures. 

In spite of the large amount of work which has been done on nitrogen pentoxide, it is planned to carry out a still more precise measurement of the decomposition rate in the gas phase. The constancy of the energy of activation at different temperatures is a matter of great theoretical importance. Although few gas reactions in chemical kinetics are more accurately known, the present meas-... 

On completion of his graduate training he became an instructor in the Chemistry Department of the University of Wisconsin, 1927-1928, and research associate in the following year. There, in association with Professor Farrington Daniels, he made his first major contribution to reaction kinetics—and that an experimental one—the demonstration that in liquid solvents, as in the gaseous phase, the decomposition of nitrogen pentoxide was a unimolecular reaction. How puzzling unimolecular processes were at that time can be fully appreciated only by those who then learned of their... 

A great many reactions follow first-order kinetics or pseudo first-order kinetics over certain ranges of experimental conditions. Among these are many pyrolysis reactions, the cracking of butane, the decomposition of nitrogen pentoxide (N2O5), and radioactive decay processes. 

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