Analytical resolution of a parallel second-order reaction mechanism

CROCE, A.; MOGNI, L.; VICENTE IRRAZÁBAL, C.

INTERNATIONAL JOURNAL OF CHEMICAL KINETICS

Willey Periodicals, Inc.

Año: 2003 vol. 35 p. 246 - 251

0538-8066

The competition among the three different elementary second-order processes involving the radicals A and B, A + A ---> A2                (1)A + B ---> AB                (2)B + B ---> B2                (3)is frequently established in many combustion and atmospheric chemistry systems. The analytical resolution of the above mechanism for kAB = 2kAA and kAB = 2kBB, that is, for a cross-combination ratio f = kAB/(kAAkBB)1/2 = 2, is well-known, but it has been claimed not to exist for  phi  differento to 2.In the present paper an analytical resolution of the system (1)-(3), performed under the condition kAB different to 2kAA and kAB  different to 2kBB, leads to       The mathematical procedure leading to this equation and the equation itself are valid independently of the nature of the products of the reactions (1), (2) and (3), that is, recombination or disproportionation products, provided that the reactants and the order of the reactions remain the same.The comparison with numerical integration for exemplary cases is performed. The solutions for the particular cases kAB different to 2kBB or kAB different to 2kAA are also presented.