文章基本信息

标题：Understanding Complexometric Titrations of Metal Cations with Aminopolycarboxylic Acids (EDTA and Analogs) within the frame of the Notion of Reactions between Groups of Chemical Species
本地全文：下载
作者：Maria Michela SALVATORE ; Francesco SALVATORE
期刊名称：World Journal of Chemical Education
印刷版ISSN：2375-1665
电子版ISSN：2375-1657
出版年度：2015
卷号：3
期号：1
页码：5-21
DOI：10.12691/wjce-3-1-2
语种：English
出版社：Science and Education Publishing
摘要：In spite of the apparent technical simplicity with which visual complexometric titrations of metal cations with aminopolycarboxylic acids titrants are performed, a complex chemistry takes place in the titrated solution during the titration, due to the chemical environment and to the insuppressible chemical properties of metal cations, aminopolycarboxylic acids and metallochromic indicators. This chemical complexity makes rigorous exposition and evaluations of complexometric titrations arduous. Nonetheless, by the introduction of the notions of groups of chemical species and reactions between groups of chemical species (with the connected concept of conditional formation constant), a frame is created within which complexometric titrations with aminopolycarboxylic acids can be collocated and which allows a reasonably simple presentation and evaluation of the analytically relevant aspects of this type of titrations. In a sense, the well known concept of conditional complex formation constant is updated in a way that facilitates understanding and use.
关键词：aminopolycarboxylic acids; complexometric titrations; conditional formation constant; EDTA; magnesium; Eriochrome Black T; water hardness