THE STANDARD STATE FOR EXCHANGEABLE CATIONS
- 1 August 1980
- journal article
- research article
- Published by Wolters Kluwer Health in Soil Science
- Vol. 130 (2) , 64-67
- https://doi.org/10.1097/00010694-198008000-00003
Abstract
It is proposed that the standard state for exchangeable cations be selected as mole fraction one-half, rather than the conventional choice of unity. This leads to a more rational interpretation of the thermodynamic equilibrium constant as ion affinities for a surface and greatly simplifies the calculation of thermodynamic functions. The necessity of a complete ion exchange isotherm is eliminated. An example of Li+-Mg2+ exchange on Yolo loam soil is given. It is proposed that the standard state for exchangeable cations be selected as mole fraction one-half, rather than the conventional choice of unity. This leads to a more rational interpretation of the thermodynamic equilibrium constant as ion affinities for a surface and greatly simplifies the calculation of thermodynamic functions. The necessity of a complete ion exchange isotherm is eliminated. An example of Li+-Mg2+ exchange on Yolo loam soil is given. © Williams & Wilkins 1980. All Rights Reserved.This publication has 1 reference indexed in Scilit:
- Thermodynamics and Ion Exchange PhenomenaTransactions of the Kansas Academy of Science, 1950