一种简便的极弱酸碱电位酸碱滴定曲线拟合方法  

A facile method of curve fitting of potentiometric acid-base titration data of very weak acids and bases

作　　者：林振宇[1] 刘建华[1] 陈国南[1] 

机构地区：[1]福州大学化学系,福建福州350002

出　　处：《福州大学学报（自然科学版）》2001年第3期96-99,共4页Journal of Fuzhou University(Natural Science Edition)

基　　金：福建省科技三项基金资助项目! (K990 40 )

摘　　要：提出测定极弱酸极弱碱的电位酸碱滴定拟合方法 .根据极弱酸 (或极弱碱 )滴定过半中和点以后溶液的酸碱性特性 ,采用简单的工作曲线法测定被测溶液中的质子 (或氢氧根 )浓度 ,在实验条件下溶液中二氧化碳不影响测定 .讨论了加权、选点等问题 ,用模拟数据作了验证 ,并测定了氯化铵、硼酸、苯酚、苯胺、醋酸钠及六亚甲基四胺等极弱酸和极弱碱以及作为二元碱的碳酸钠 。A new procedure of potentiometric acid-base titration and curve fitting is described for determining very weak acids and bases. Based on specific properties of acidity of basicity of the solution titrated after the very weak acids or bases have been half neutralized, the concentration of proton or hydroxyl in the solution is measured by a simple calibration curve method. The measurement is not affected by carbon dioxygen under experimental conditions. The selections of weighting factors and experimental points are discussed. The procedure is examined with simulated data. Some very weak acids and bases such as ammonium chloride, boric acid, phenol, aniline, sodium acetate, hexamethylenamine and sodium carbonate are determined by the method described in the paper. The results show that it is possible to determine the very weak acids and bases with a satisfactory accuracy and precision.

关 键 词：极弱酸 极弱碱 电位酸碱滴定 非线性回归 曲线拟合方法 残差分析 

分 类 号：O655.22[理学—分析化学]