On-line version ISSN 1678-4618
ROSSI, A. V. and TUBINO, M.. About the kinetics and mechanism of the reactions of 4-(2-pyridylazo)-resorcinol, with Zn2+, Cu2+ and Zn2++Cu2+ equimolar mixtures, in aqueous solutions. Eclet. Quím. [online]. 2003, vol.28, n.1, pp. 55-62. ISSN 1678-4618. http://dx.doi.org/10.1590/S0100-46702003000100007.
The kinetics and mechanism of the reactions between 4(2pyridylazo)-resorcinol and Zn2+, Cu2+ and Zn2++Cu2+ equimolar mixtures were studied. The reactions were performed in aqueous solution (pH = 8.5, borate buffer) and monitored spectrophotometrically at 500 nm using stopped-flow technique. Spectral and kinetic data indicate that the Zn2++Cu2+ equimolar mixture behaves as an unique species and it can be attributed to the interactions of Zn2+ and of Cu2+ with water molecules in the aqueous solution. A mechanism is proposed and the rate constants are calculated.
Keywords : PAR; zinc; copper; kinetics; mechanism.