物理化学实验改进:原电池电动势与液接电势的测定  

Improvement of Physical Chemistry Experiment: Measurement of Electromotive Force and Liquid Junction Potential of Primary Batteries

作　　者：徐开颜 高梅霞 方正法[1] 杨素芳[1,2] Kaiyan Xu;Meixia Gao;Zhengfa Fang;Sufang Yang(College of Chemistry and Chemical Engineering,Hunan Normal University,Changsha 410081,China.;National Demonstration Center for Experimental Chemistry and Chemical Engineering Education,Hunan Normal University,Changsha 410081,China.)

机构地区：[1]湖南师范大学化学化工学院,长沙410081 [2]湖南师范大学化学化工国家级实验教学示范中心,长沙410081

出　　处：《大学化学》2024年第1期248-253,共6页University Chemistry

基　　金：湖南师范大学校级教学改革项目(校行发教务字[2015]90号)。

摘　　要：本文针对原电池电动势测定实验中被忽略的液接电势,设计了一套测定原电池总电动势的实验装置,将其纳入实验内容,并引入液接电势、可逆电池电动势与原电池总电动势的关系的探究。改进装置简单、成本低,所测液接电势具有较好的稳定性、重现性。改进后的实验更完整、真实地体现了原电池总电动势的组成,而并非仅局限于可逆电池电动势的测定,有助于学生建立完整、正确的原电池认知和电化学知识体系。此外,测出的浓差液接电势可应用于离子迁移数的计算,将电动势法测离子迁移数融入教学,实现课程融合,提升学生对知识的综合运用能力。Expanding upon the"Basic Physical Chemistry Laboratory"module focused on the measurement of primary battery electromotive force(EMF),this paper introduces a novel experimental design.The design incorporates the often-neglected liquid junction potential,investigating its relationship with reversible battery EMF and the total EMF of the primary battery.The revised apparatus is cost-effective,straightforward,and offers stable and reproducible measurements for liquid junction potential.This improved experiment provides a more comprehensive and accurate representation of the components contributing to the total EMF of the primary battery,transcending the limitations of merely measuring reversible battery EMF.As a result,the experiment aids students in forming a well-rounded and accurate understanding of primary batteries and the underlying principles of electrochemistry.Furthermore,the measured liquid junction potential is applicable in calculating ion transference numbers,allowing for the integration of this advanced concept into the curriculum and thereby bolstering students'comprehensive skill set.

关 键 词：液接电势 可逆电池电动势 半透膜 

分 类 号：O64[理学—物理化学] G64[理学—化学]