在25～40 ℃区间内用分光光度法在碱性介质中研究了二(过碲酸)合银(Ⅲ)离子氧 化苹果酸的动力学及机理.实验结果表明反应对二(过碲酸)合银(Ⅲ)离子是准一级的,对苹果 酸是分数级.准一级速率常数kobs随［OH-］及［TeO2-2］的增大分别 减小,且发现有正的盐效应. 根据实验结果,提出了包含有双电子转移的反应机理,据此导出了一个能解释全部实验事实的 速率方程,并求出了速控步的速率常数及25 ℃时的活化参数.
The kinetics of oxidation of malic acid by ditell uratoargentate(Ⅲ)ion was studied by spectrophotometry in alkaline medium. The reaction rate sho wed first order dependence on Ag(Ⅲ)and positive fractional order dependence on malic acid.kobs decreased with the increase in ［OH-］［TeO2- 4］ respectively. The active species and a plausible mechanism involving two-electron transfer have b een proposed .All the experimental phenomena can be explained by the rate equa tion derived from the mechanism. The rate constants of the rate-determining ste p together with the activation parameters have also been calculated.
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