Abstract
The kinetics and mechanism of the reactions between 4-(2-pyridylazo)-resorcinol and Zn 2 +,Cu 2+ and Zn 2+ +Cu 2+ 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 Zn 2+ +Cu 2+ equimolar mixture behaves as an unique species
and it can be attributed to the interactions of Zn 2+ and of Cu 2+ with water molecules in the aqueous
solution. A mechanism is proposed and the rate constants are calculated.
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