About the kinetics and mechanism of the reactions of 4-(2-pyridylazo)-resorcinol, with Zn2+, Cu2+ and Zn2++Cu2+ equimolar mixtures, in aqueous solutions

Abstract

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.

Kinetic Monitoring of Electrophoretically Induced Solute Reaction by Axial Absorption Detection with Liquid-Core Waveguide

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On-line Determination of Zinc in Water and Biological Samples after Its Preconcentration onto Zincon Anchored Polyurethane Foam

“…21 A plausible mechanism of this reaction can be proposed by two steps involving the exchange of water molecules of salvation.…”

Determination of trace transition metals in environmental matrices by chelation ion chromatography

“…Several sensitive methods for the determination of heavy metals, including atomic absorption spectrometry, inductively coupled plasma optical emission spectroscopy, and ion chromatography have all been used. Furthermore, in the last decade, chelation ion chromatography (Shaw et al 2003;Santoyo et al 2000;Sarzanini and Bruzzoniti 2001;Cardellicchio et al 1997Cardellicchio et al , 1998Cardellicchio et al , 1999Basta and Tabatabai 1990;Sarzanini and Cavalli 1998;Rossi and Tubino 2003;Sarzanini and Mentasti 1997;Shaw and Haddar 2004;Divjak et al 1998;Ding et al 2000a, b;Motellier and Pitsch 1996;Nesterenko 2002;Jones and Nesterenko 1997;Siriraks et al 1990;Lu et al 1998;Bashir and Paull 2002;Nesterenko and Jones 1997;Bruno et al 2006;Lasheen et al 2006) has become one of the main powerful analytical methods for the analysis of some metals in complex matrices. Ion chromatography allows the determination of oxidation state speciation (i.e., Fe 2+ and Fe 3+ ) and thus is a useful tool for bioavailability studies of toxic metals in the environment.…”