范宝路,刘阳,周雷,林毅,南峰,沈宇

• 1:淮阴工学院数理学院

摘要(Abstract)：

水在自然界中广泛以水溶液形式存在，是生命活动不可或缺的重要物质。强电解质在水中完全离解为自由离子，形成导电性溶液，其电导率与离子浓度密切相关。基于L.Onsager提出的极限定律，离子在无限稀释条件下的迁移率趋于恒定值，主要受水分子热运动的影响。本文以氯化钾(KCl)稀溶液为研究对象，在室温条件下通过低电压高精度电导率测量，获得不同浓度下的电导数据，并对其进行拟合分析，进而求得迁移率极限值及溶剂黏度。结合分子运动理论，本文进一步计算了平均碰撞时间，并采用等效硬球模型估算了离子与水分子热运动的有效碰撞截面。结果表明，离子迁移率随浓度降低而趋于饱和，有效碰撞截面远大于几何截面，表明碰撞过程中存在显著的库仑相互作用。本文所采用的实验方法和分析模型建立在大学物理与统计物理的基础之上，具有良好的教学价值，适用于相关课程中热运动、电解质输运等内容的实例拓展，帮助学生理解抽象物理模型与实际过程之间的联系。

关键词(KeyWords)： 迁移率;平均碰撞时间;碰撞截面;电导率;电解质

Abstract:

Keywords:

基金项目(Foundation): 淮安市自然科学研究计划项目(HAB201906)资助;; 江苏省“双创博士”人才项目;; 教育部人文社科青年基金项目(25YJC760067)

作者(Author): 范宝路,刘阳,周雷,林毅,南峰,沈宇

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