本文采用分光光度法研究了在碱性介质中,恒定离子强度下,烟酸离子被高锰酸钾氧化的动力学。在碱性介质中,高锰酸钾与烟酸离子的反应呈现2:1的化学计量比(KMnO4:烟酸离子)。该反应对高锰酸钾浓度呈一级反应,对烟酸离子和碱浓度均呈小于一级的反应。反应速率随着离子强度的增加和介质极性的降低而增加。初期加入反应产物对速率影响不大。提出了涉及氧化剂和底物形成中间复合物的机理。评估了缓慢步骤的速率和活化参数。
The kinetics of oxidation of nicotinate ion by permanganate in alkaline medium at a constant ionic strength has been studied spectrophotometrically. The reaction between permanganate and nicotinate ion in alkaline medium exhibits 2 : 1 stoichiometry KMnO4 : Nicotinate ion). The reaction shows first order dependence of rate on permanganate concentration and less than unit order dependence each in nicotinate ion and alkali concentrations. Reaction rate increases with increase in ionic strength and decrease in solvent polarity of the medium. Initial addition of reaction products did not affect the rate significantly. A mechanism involving the formation of an intermediate complex between oxidant and substrate has been proposed. The rate and the activation parameters for the slow step have been evaluated.
本文采用分光光度法研究了在碱性介质中,恒定离子强度下,烟酸离子被高锰酸钾氧化的动力学。在碱性介质中,高锰酸钾与烟酸离子的反应呈现2:1的化学计量比(KMnO4:烟酸离子)。该反应对高锰酸钾浓度呈一级反应,对烟酸离子和碱浓度均呈小于一级的反应。反应速率随着离子强度的增加和介质极性的降低而增加。初期加入反应产物对速率影响不大。提出了涉及氧化剂和底物形成中间复合物的机理。评估了缓慢步骤的速率和活化参数。