21. Electrolyte Solutions

A discussion of the chemical drive of solvation and hydration processes, respectively, leads to the introduction of the basic concept of electrolytic dissociation, the disintegration of a substance in solution into mobile ions. Subsequently, we learn about the migration of these ions along an electric potential gradient as a special case of spreading of substances in space. The ionic mobilities provide a link to conductance and the related quantities conductivity as well as molar and ionic conductivity. For determining the conductivity of ions experimentally, the introduction of the term transport number which indicates the different contribution of ions to the electric current in electrolytes is very useful. In the last section, the technique for measuring conductivities is presented as well as its application in analytical chemistry where conductometric titration is a routine method.