大学化学 >> 2015, Vol. 30 >> Issue (4): 63-67.doi: 10.3866/pku.DXHX20150463

师生笔谈 上一篇    下一篇

稀溶液中化学势的计算以及渗透压公式的推导

陈飞武, 韦美菊, 叶亚平, 袁文霞   

  1. 北京科技大学化学与生物工程学院 北京 100083
  • 发布日期:2015-08-14
  • 通讯作者: 陈飞武 E-mail:chenfeiwu@ustb.edu.cn
  • 基金资助:

    北京科技大学研究型示范教学项目;北京科技大学教育教学改革项目(Nos.JG2011Z09,JG2013M41)

Calculation of Chemical Potential in Dilute Solution and Derivation of the Osmotic Pressure Equation

Chen Feiwu, Wei Meiju, Ye Yaping, Yuan Wenxia   

  1. School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China
  • Published:2015-08-14

摘要:

将溶液中某组分化学势的计算方式归纳为两种:(1)利用气液平衡时,溶液中某组分的化学势和气相中该组分的化学势相等这一关系来计算;(2)利用溶液中某组分化学势的全微分表达式直接积分来计算。在此基础上,给出了渗透压公式的一种新推导方式,并指出部分物理化学教材关于渗透压定义(Π=p2-p1)的不合理性以及推导渗透压时存在的不妥之处。

关键词: 化学势, 渗透压, 溶液, 化学势

Abstract:

There are two ways to calculate the chemical potential of a component in solution. One is that, in the gas-liquid phase equilibrium, the chemical potential of a component in solution is equal to its corresponding chemical potential in the gas phase; thus, the chemical potential of the component in solution can be easily obtained through the gas-liquid equilibrium once its chemical potential in gas phase is known. Another way is to integrate directly the total differential of the chemical potential of the component in solution. Based on this, a new way to derive the osmotic pressure equation is presented in this article. It is also pointed out that the definitions about the osmotic pressure in some domestic physical chemistry textbooks are not reasonable and the derivation of the osmotic pressure equation is not valid.

Key words: Chemical potential, Osmotic pressure, Solution, Chemical potential

MSC2000: 

  • O6