高精度散射光度滴定法测定Cl^-的含量  

To Determine to Concetration of Cl^- with Highli-accurate Nephelometric Titrimetry

作　　者：李成蓉[1] 詹先成[1] 钟术光[1] 林涛[1] 李琳丽[1] 涂莉[1] 

机构地区：[1]四川大学华西药学院物理化学教研室,成都610041

出　　处：《华西医科大学学报》2002年第4期645-647,共3页Journal of West China University of Medical Sciences

基　　金：国家自然科学基金资助 (批准号 3 9770 882 )

摘　　要：目的　用检测溶液浑浊程度来指示 Ag+滴定 Cl-的滴定终点 ,测定 Cl-的含量。方法　将一束光线通入待测溶液中 ,在溶液中与其垂直的方向上检测散射光相对强度 ,随着 Ag NO3溶液的加入 ,溶液将逐渐变得浑浊 ,散射光相对强度逐渐增强 ,如果沉淀反应完全 ,散射光相对强度将在化学计量点处达最大值 ,由此可判断滴定终点 (称散射光度滴定法 )。结果　该滴定方法较荧光黄和铬酸钾指示剂法适用于更低浓度的 Cl-含量检测 ,在适当的条件下该方法的精密度和准确度均可小于千分之二。结论　散射光度滴定方法可用于测定较低浓度的Objective To introduce a new method for indicating the titration end point of Cl - with Ag + by the measurement of the relative intensity of scattered light in the titrate solution. Methods Light on the detectors creates a current flow through the diodes. With the addition of the AgNO 3 solution, the titrate solution will be turbid and the intensity of the scattered light in the solution will increase gradually and reach the maximum at the stoichiometric point; thus the titration end point can be indicated. Results The new method is appropriate for the solution with lower concentration of Cl -, compared with the fluorescein and potassium chromate indicator method. Its accuracy and precision are better than two thousandths under suitable conditions. Conclusion The new method can be used to indicate the titration end point of Cl - with Ag +.

关 键 词：散射光 AgCl溶胶 Cl^-含量 

分 类 号：O657.3[理学—分析化学]