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本刊1979年第1期发表了李醒夫同志的“络合滴定终点理论的探讨”一文,读后觉得文中有些问题值得进一步讨论。例如文中曾得出结论:“干扰离子和被滴定离子浓度愈高,干扰离子的络合常数愈大,指示剂偏差愈大,滴定终点愈不敏锐”(着重点是本文作者加的)。很明显,得出被滴定离子浓度愈高滴定终点愈不敏锐这一结论,似与实际情况不符。李文以dx/dy(加入少量络合剂时指示剂颜色变化的速度)表示终点敏锐度,这可能是不够恰当的。这里有两个问题:1.不用指示剂检测终点时,也存在终点敏锐度问题;2.终点敏锐度
The first issue of 1979 issue of Comrade Li Xingfu “complex titration endpoint theory” one article, after reading some of the problems that the article is worth further discussion. For example, the article has concluded: “The higher the interference ions and the concentration of the titrated ion, the larger the complex ion interference constant, the greater the deviation of the indicator, the less acute end point titration” (emphasis added). Obviously, the conclusion is drawn that the higher the titration ion concentration is, the less sharp the end point of the titration is. It seems to be inconsistent with the actual situation. Levin dx / dy (when adding a small amount of complexing agent indicator color change speed), said end point acuity, which may not be appropriate. There are two problems here: 1. There is also a problem of end point acuity when there is no indicator to detect endpoints; 2. End point acuity