الفهرس 
Aim of the present workOnly 14 pages are availabe for public view
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Abstract
The present work comprises a study of the kinetics and mechanism of oxidation of binary chromium (III) complex involving diacetyl monoxime (DAM) and oxidation of ternary chromium (III) complex involving dimethyl glyoxime(DMG) with glycine by periodate. 1- Chapter I: Introduction :The introduction contains electron transfer, outer- sphere and inner-sphere mechanisms have been discussed.This chapter contains the nature and properties of chromium(III) and its complexes have been briefly discussed. The nature, chemical behavior and different species in aqueous solutions of periodate have been reported. The literature concerning on the oxidation of organic compounds by periodate are mentioned. diacetyl monoxime acid (DAM) as tumor inhibitors, antimicrobial agents, antituberculous and antileukemic agents has been briefly discussed. Glycine as a biological thiol exists widely inside and outside of cells has been briefly discussed.2- Chapter II: EXPERIMENTAL:Encompasses chemicals, preparation and characterization of metal complexes, the experimental procedures, and the technique for the kinetic studies and methods for the data determination.3- Chapter III: Results and discussion :Comprises the layout of the results obtained and their discussions. The effect of various parameters on the rate of reaction has been discussed. This chapter contains two parts:Part (I):The kinetics of oxidation of [Cr-DAM] by periodate in aqueous solutions have been studied. The rates of the reaction increases with the increasing of periodate, temperature and pH. The rate of the reaction is independent on the complex concentration and independent on ionic strength. The oxidation of this complex obeys the following rate law. d [CrVI] / d t ={ k2 (1 /[H+]) }[ IO4-] [Cr -DAM] Where; kobs. = {k 2(1 / [H+])} [IO4-] An inner-sphere process may be still accommodating through replacement of coordinate H2O in the one species, by periodate. The enthalpy of activation ∆H* and entropy of activation ∆S* also are calculated. Part (II). The kinetics of oxidation of [Cr-DMG.gly.] by periodate in aqueous solutions have been studied. The rate of the reaction increases with the increasing of periodate, temperature and pH. The reaction is independent on the complex concentration and decreases with ionic strength increasing. The oxidation of this complex obeys the following rate. d [CrVI] / d t =(k2 + k3 / [H+]) [IO4-] [Cr-DMG.gly.] Where, kobs. = (k2 + k3 / [H+]) [IO4-] Two alternative mechanisms may be considered for the oxidation of [Cr(DMG)(gly.)] by periodate . The first alternative inner- sphere mechanism may be accommodated through replacement of coordinate H2O by periodate species and the second alternative mechanism may be accommodated through reactive species IO4- coordinates to form the precursor complex. The rate law is consistent with a mechanism including two electron transfer paths; one is first order while the second is second order in periodate. The enthalpy of activation ∆H* and entropy of activation ∆S* also are calculated.