标准加入法在酸碱分析中的应用

本文推导了单元酸标准加入法的线性公式。在被测酸溶液中,等量加入同种酸的标准溶液多次,并记录pH值,代入线性公式计算后即可得一直线,该直线在纵轴上的截距为被测酸浓度,斜率为该酸的条件稳定常数。本文还对单元酸及其共轭碱的标准加入法同时测定进行了研究。

Application of Standard Addition Method in the Analysis of Acid-Base

The multiple standard addition method was applied to the analysis of acids, and the linear equations for this purpose were derived. The experiment was performed by stepwise addition of equal standard to the sample solution. The measured data were calculated and a straight line was obtained. The initial concentration of the acid, CHA, is from the intercept and the conditional stable constant, KHA,is from the slope. This method was applied to the determination of formic acid, acetic acid, ascorbic acid, benzoic acid, salicylic acid, etc. with satisfactory results. Further more, the standard addition method was applied to the determination of mixture of weak acid and its conjugate base with good results.