الفهرس 
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Abstract
The present work comprises a study of the kinetics and mechanism of oxidation of Binary and ternary chromium (III) complexes involving N-(2-Acetamido)imino-diacetate and amino acid ( valin ) by periodate. 1- Chapter I, Introduction, Electron transfer, outer- sphere and inner-sphere mechanisms have been discussed. The nature,properties and biological activity of chromium (III) and its complexes have been briefly discussed. The nature, properties, chemical behavior and different species in aqueous solutions of periodate have been reported. The literature concerning the oxidation of organic and inorganic compound in aqueous solutions and in aqueous organic solvents by periodate are mentioned. The nature, properties and biological important of amino acids and ADA and their metal complexes have been briefly discussed. 2- Chapter II, Experimental, Chemicals, preparation and characterization of metal complexes, the experimental procedures and the technique for the kinetic studies and methods for the data were determined. 3- Chapter III, Results and discussion, This part includes 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: (i) Part (I), the kinetics of oxidation of [CrIII(ADA)(H2O)]+ by periodate in aqueous solutions have been studied. The rate of the reaction increases with the increasing of (periodate concentration, temperature, pH). This reaction is first order respected to complex concentration. The oxidation of this complex obeys the following rate law. d[CrVI]/dt=[CrIII(ADA)(H2O)2]+[H5IO6]{k6K6+(k7K7K5/[H+])} An inner- sphere process may be still accommodating through replacement of coordinate H2O by periodate species. The enthalpy of activation ∆H* and entropy of activation ∆S* also were calculated. (ii) Part(II), the kinetics of oxidation of [CrIII(ADA)(Valin)(H2O)2] by periodate in aqueous solutions have been studied. The rate of the reaction increases with the increasing of pH and periodate concentration. The reaction is dependent on the ionic strength. The oxidation of this complex obeys the following rate law. d[CrVI]/dt=[CrIII(ADA)(VAL)(H2O)2][H5IO6]{k6K6+(k7K7K5/[H+])} An inner- sphere process may be still accommodating through replacement of coordinate H2O by periodate species. 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 were calculated.