Getting information from electrical conductivity data

3 Getting information from electrical conductivity data 

It is convenient to summarize the recommended procedures to obtain information on the transport coefficients and thermodynamic properties of electrolyte from measured electrical conductivity above 200 °C. At high temperature the dielectric constant of water is low enough and even single 1 1 electrolytes which are fully dissociated at room temperature could associate in a degree that increases with increasing temperature and decreasing density (pressme). Therefore, the determination of A°, which is a measme of the ion-solvent interaction and is related to the ion solvation, should be performed by using some of the eqrrations vahd for associated electrolytes (Equations (4.16), (4.17) or (4.18)). 

The fitting of the experimental data beyond the limit imposed by the condition Kr4 0.1 could yield large over-estimation of A in the low-density supercritical region, as discussed in the following section. In this region the contribution of the electrophoretic effect to the concentration dependence of the molar conductivity is expected to be lower (Ibuki et al., 2000) and the difference among the equations for associated electrolytes becomes less important. 

For highly associated electrolytes, as those formed by high charge ions at high temperatme and low density, the 

---

So from electrical data, it is possible to get information on partial thermodynamic functions of the salt and then develop thermodynamic models for quantitative interpretation of the conductivity variation with composition. These models are not very different from those already developed for molten salt mixtures or metallic alloys. 

---