摘要
本文应用EDTA作为钙离子缓冲溶液,对自制涂丝钙离子选择电极(Ca-CWISE)进行了校正,与用标准系列稀释法相比,电极的线性范围扩大了三个数量级。文章还利用自制Ca-CWISE,采用Thomas等所用的简易pH-pM法,测定了柠檬酸钙的浓度稳定常数,IgK_(CaCit^-)=3.86(30℃,I=0.1)。
This paper describes that calcium ion beffers, EDTA, is used for calibration of coated wire calcium ion selective electrodes made in our laboratory. Compared with the calibration by serial dilution standards, the working ranges of coated wire calcium ion selective electrode have been extended over three orders of mag- nitude. Detection limit is about 2×10^(-8) mol/L The concentration formation constant of calcium citrate complex was deter- mined by this electrode, i. e. lgK_(CaCi)=3. 86(30℃, I=0. 1) .
关键词
电极
校正
电化学分析
稳定常数
ion elective electrode
calibration of electrode
determination of stability constants
