Kinetics and mechanism of the formation of FeII(edta)NO in the system FeII(edta)/NO/HONO/NO2- in aqueous solutions
Kinetics and mechanism of the formation of FeII(edta)NO in the system FeII(edta)/NO/HONO/NO2- in aqueous solutions
复制标题
水溶液中 FeII(edta)/NO/HONO/NO2- 体系中 FeII(edta)NO 形成的动力学和机理
DOI：
10.1021/ic00292a007
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发表时间：
1988
影响因子：
4.6
通讯作者：
R. Eldik
中科院分区：
文献类型：
--
作者：
V. Zang;M. Kotowski;R. Eldik
NO、HONO和N02“在水溶液中与FeN(EDTA)反应生成Fen(EDTA)NO，与NO的反应速度太快，而与H0N0/N02”的反应可以用停流技术进行动力学跟踪。该反应发生在两条不同级数的平行路径上，即。Fen(EDTA)浓度分别为假一级和假零级。每条路径的贡献很大程度上取决于所采用的pH值和总亚硝酸盐浓度。反应动力学可用速率定律-d[FeN(EDTA)]/dR=U，[HONO]2+kb[FeN(EDTA)][HONO]来描述，其中ka和kb在25℃和0.5M离子强度下分别为62±12和90±16M~(-1)·S~(-1).提出的反应机理包括NO+的生成速率控制和FeN(EDTA)将HONO还原为NO，以解释平行反应路径.并与已有的文献数据进行了比较.
NO, HONO, and N02" react with Fen (edta) in aqueous solution to produce Fen (edta) NO. The reaction with NO is too fast for conventional stopped-flow and-jump techniques, whereas the reaction with H0N0/N02" can be followed kinetically by using stopped-flow techniques. This reaction occurs in two parallel paths of different order, viz. pseudo first and pseudo zero order in Fen (edta) concentration, respectively. The contribution of each path strongly depends on the pH and total nitrite concentration employed. The kinetics of the reaction can be described by the rate law-d [Fen (edta)]/dr= U,[HONO] 2+ kb [Fen (edta)][HONO], where ka and kb havethe values 62±12 and 90±16 M" 1 s'1, respectively, at 25 C and 0.5 M ionic strength. The suggested mechanism involves the rate-determining formation of NO+ and the reduction of HONO to NO by Fen (edta), to account for the parallel reaction paths. The results are discussed in comparison to the availableliterature data.