The analytical resolution of parallel first- and second-order reaction mechanisms

N. B. CABALLERO; A. E. CROCE; E. PENSA; C. VICENTE IRRAZÁBAL

INTERNATIONAL JOURNAL OF CHEMICAL KINETICS

JOHN WILEY & SONS INC

Año: 2010 vol. 42 p. 562 - 566

0538-8066

Given the species A1 and A2, the competition among the three different elementary processes A1 → products (1) A1 + A2 → products (2) A1 + A1 → products (3) is frequently found in thermal and photochemical reaction systems. In the present paper an analytical resolution of the system (1)–(3), performed under plausible contour conditions, namely, finite initial molar concentrations for both reactants, [A2]0 and [A1]0, and non zero reaction rate coefficients k1, k2 and k3, leads to the equation [A1]=((((δ [A2]))^γ) – [A2])/ β) – α, where α = k1/2k3, γ = β+1=2k3/k2 and δ = ([A2]0+ β [A1]0 + βα) / (([A2]0)^γ). The comparison with a numerical integration employing the fourth order Runge−Kütta Algorithm for the well−known case of the oxidation of organic compounds by ferrate ion is performed.