7. Determination by conductometry

7.1 Reminders

The ease with which a solution conducts electricity depends on the concentration of ions in the solution, and also on their nature. If there is an equilibrium between ions in a solution, its conductivity is a measure of the position of the equilibrium. Measuring the conductivity of a solution can provide access to all the concentrations in solution, and therefore to the equilibrium constants that prevail. This technique was used as early as 1865-1910. Most of the results obtained at that time proved to be particularly accurate.

Conductometry is concerned with ionic conduction. We measure the conductance (inverse of resistance) of a column of solution between two metal electrodes, usually platinum-platinum. The two electrodes are separated by the...