配位滴定法测定锌含量的合适酸度条件研究  

Study on Suitable Acidity Conditions for Determination of Zinc Content by Coordination Titration

作　　者：苏铁军 夏金强 李克娥[2] SU Tiejun;XIA Jinqiang;LI Ke’e(Jingzhou University School of Petroleum and Chemical Engineering,Jingzhou,Hubei 434020,China;Yangtze University School of Information and Mathematics,Jingzhou,Hubei 434023,China)

机构地区：[1]荆州学院石油与化学工程学院,湖北荆州434020 [2]长江大学信息与数学学院,湖北荆州434023

出　　处：《中国无机分析化学》2022年第3期145-150,共6页Chinese Journal of Inorganic Analytical Chemistry

基　　金：湖北省高等学校省级教学研究项目(2021532);湖北省教育厅科学技术研究项目(B2020339)。

摘　　要：调节待测体系的pH值是配位滴定中一种重要的选择性滴定手段。采用CTE1.0程序计算了不同酸度条件下的终点误差,同时用配位滴定法测定了模拟样品和市售药品中的锌含量。计算结果和实测结果均表明,在不含钙离子的待测体系中,测定锌离子含量的合适酸度条件为pH=6;在钙、锌混合离子溶液中,测定锌含量的合适酸度条件为pH=5。平行测定实验的相对标准误差为1.6%,加标回收率为99.1%~102%。CTE1.0是一款计算配位滴定终点误差的有力工具,计算所得结果可为设计分析方案提供重要依据。Adjusting the pH value of the system to be measured is an important selective titration method in coordination titration.The titration error under different acidity conditions was calculated by CTE1.0 program,and the content of zinc on simulated samples and commercial drugs was determined by coordination titration.The calculated and measured results show that the suitable acidity condition is pH=6 when content of zinc ion will be determined in the system without calcium ion.In the mixed ionic solution containing calcium ion and zinc ion,the appropriate acidity condition is pH=5 when content of zinc ion will be determined.The relative standard error of parallel determination experiment is 1.63%,and the recovery is 99.1%—102%.CTE1.0 is a powerful tool for calculating the end point error of coordination titration.The calculated result by CTE1.0 is an important basis for the design of analysis scheme.

关 键 词：配位滴定 锌离子 终点误差 酸度条件 

分 类 号：O655.2[理学—分析化学]