TITLE:
Periodate Oxidation of a Ternary Complex of Nitrilotriacetatochromium(III) Involving ß-Alanine as Co-Ligand
AUTHORS:
Hassan A. Ewais, Ahmed H. Abdel-Salam, Amal S. Basaleh, Mohamed A. Habib
KEYWORDS:
Nitrilotriacetatochromium(III), Ternary Complex, Periodate Oxidation, Inner-Sphere Mechanism, Thermodynamic Activation Parameters
JOURNAL NAME:
Open Journal of Inorganic Chemistry,
Vol.8 No.4,
October
15,
2018
ABSTRACT: The kinetics of the periodate oxidation of chromium(III)-complex, [CrIII(NTA)(Ala)(H2O)]-(NTA = Nitrilotriacetate and Ala = ß-alanine) to Cr(VI) have been carried out for the temperature range 15°C - 35°C under pseudo-first order conditions, >>[complex]. Reaction obeyed first order dependence with respect to and [Cr(III)], and the rate of reaction increases with increasing of pH for the range 3.40 - 4.45. Experimentally, the mechanism of this reaction is found to be consistent with the rate law in which the hydroxo species, [CrIII(NTA)(Ala)(OH)]2- is considerably much more reactive than their conjugate acid. ΔH* and ΔS* have been calculated. It is proposed that electron transfer occurs through an inner-sphere mechanism via coordination of to chromium(III).