加酸顺序对碱性高锰酸钾法测定的影响

Influence of Sequence of Adding Acid on Measurement of Alkaline KMnO_4 Method

本文通过大量实验,对现行碱性 KMnO_4法进行了研究、探讨,发现该方法在加热消化后先加入硫酸酸化,造成测量结果不易平行,准确度下降,Cl^-干扰增大.本文采用加热消化后先加入草酸标准溶液,然后再加入硫酸酸化,明显改善了测量精密度和可比性,提高了准确度并且显著降低了 Cl^-的干扰.

Conventional alkaline KMnO_4 method is studied through a lot of experiments in this paper.It is discovered that earlier H_2SO_4 acidification after heating digestion makes the measured results balance uneasily,the accuracy and precision decrease,and Cl^- interference increase.In this study,the accuracy and precision are greatly improved and Cl^- interference is largely decreased,by means of adding oxalicaeid solution at first and then adding H_2SO_4 for acidification after heating digestion.