大学化学 >> 2022, Vol. 37 >> Issue (6): 2108083.doi: 10.3866/PKU.DXHX202108083

化学实验 上一篇    下一篇

无限稀释氯化氢水溶液中离子迁移数的测定

许新华(), 吴梅芬, 王晓岗   

  • 收稿日期:2021-08-25 录用日期:2021-09-27 发布日期:2021-12-03
  • 通讯作者: 许新华 E-mail:xxh01@tongji.edu.cn
  • 作者简介:许新华, Email: xxh01@tongji.edu.cn
  • 基金资助:
    同济大学第十五期实验教学改革专项基金项目(1380104121)

Determination of the Transference Numbers of Ions at an Aqueous Hydrochloric Acid Infinite Dilution

Xinhua Xu(), Meifen Wu, Xiaogang Wang   

  • Received:2021-08-25 Accepted:2021-09-27 Published:2021-12-03
  • Contact: Xinhua Xu E-mail:xxh01@tongji.edu.cn

摘要:

基于Debye-Hückel-Onsager理论讨论了离子迁移数与电解质溶液浓度的关系,并介绍了测定无限稀释条件下离子极限迁移数的实验方法。实验证明,测得的迁移数与溶液浓度关系可以计算为一个线性拟合函数,并外推至零浓度,从而得到极限迁移数。因此,这个传统教学实验可以做出改进,以增进学生对电解质理论的理解。

关键词: 迁移数, 无限稀释, 界面移动法, 电解质

Abstract:

The relationship between the transference numbers of ions and the concentrations of electrolyte solutions is discussed based on the Debye-Hückel-Onsager theory. An experimental method for determining the transference numbers at infinite dilution is also introduced. It is shown that the transference numbers determined as a function of the concentration of the solutions follow a linear fitting function, which can be extrapolated to zero concentration to obtain the transference number at infinite dilution. Therefore, this teaching experiment should be improved to enhance students' understanding of the principles of electrolyte theory.

Key words: Transference numbers, Infinite dilution, The moving boundary method, Electrolyte