分光光度法测定铬黑T解离常数实验设计  

Experimental Design on the Determination of Dissociation Constants of Eriochrome Black T by Spectrophotometry

作　　者：孙瑞卿 许紫婷 陈珠灵 林佳丽 Ruiqing Sun;Ziting Xu;Zhuling Chen;Jiali Lin(National Experimental Teaching Demonstration Center for Chemistry and Chemical Engineering,College of Chemistry,Fuzhou University,Fuzhou 350116,China)

机构地区：[1]福州大学化学学院,化学化工国家级实验教学示范中心,福州350116

出　　处：《大学化学》2022年第12期183-190,共8页University Chemistry

摘　　要：在分析化学实验教学基础上,引入光谱分析和数据处理,设计了用紫外-可见分光光度法测定铬黑T解离常数的实验。根据系列pH下铬黑T溶液的吸光度,利用ORIGIN进行数学拟合,推导出相应的数学模型,计算铬黑T水溶液的解离常数pKa1、pKa2、pKa3。实验方案简单高效,结果准确度高,可以拓展本科化学实验内容,深入理解酸碱解离过程,加强对仪器分析的认识和应用,培养学生实验设计、数据处理、拟合建模、推导判断的综合能力。This work aims to provide an approach to determine the dissociation constant(pKa)of Eriochrome Black T by using UV-Visible spectrophotometry.The absorbance of Eriochrome Black T was measured at different pH and the data was fitted by ORIGIN with specific function model.Based on the obtained formula,the three pKa of Eriochrome Black T can be calculated,respectively.This method is highly efficient,accurate,and easy to operate.It can also serve as an expansion for the undergraduates’chemistry laboratory,which can help cultivate the students’comprehensive ability of experimental design,data processing,and model derivation.

关 键 词：解离常数 紫外-可见分光光度法 铬黑T 

分 类 号：G64[文化科学—高等教育学] O655[文化科学—教育学]