الملخص

Abstract The kinetics of formation of azo dyes formed by reactions of Schiffs, bases, with various ortho substituents on the primary amine parts of imines with diazotized sulphanilic acid sodium salt at pH7. The optimum ratio of concentrations of dyes, reactants were (1: 10: 2.5) for (Schiff,s base: reagent: base) respectively. Experimentally, it was proved that, dyes formation followed a pseudo first order kinetic with respect to imines. The kinetics of dyes formation were studied at optimal conditions for the dyes and at a range of temperatures (10-50 ○C). This investigation included contains the evaluations of rate constants (k), half lives (t1/2) and thermodynamic parameters of activation, namely, (Ea, ∆H*, ∆S* and ∆G*). The values of these parameters were discussed and interpreted.