Electrochemistry

Abstract

When an electrolyte is dissolved in water (or in other polar solvents) it dissociates into ions. The ions themselves may always be regarded as present essentially only in the aqueous phase. The theory of electrolytic solutions is based essentially on the approach of dilute solution theory, since the existence of a solvent is guaranteed. However, the theory of electrolytic solutions is peculiar in three aspects: first, ionic reactions are extremely fast, and thus may be regarded as being always at equilibrium. Second, the condition of electrical neutrality must always be satisfied. Third, the behavior of solutes in electrolytic solutions, even at infinite dilution, is somewhat different from what it is in ordinary dilute solutions of nonelectrolytes.

The principles of thermodynamics occupy a special place among the laws of nature. For this there are two reasons: in the first place, their validity is subject only to limitations which, though not, perhaps, themselves negligibly small, are at any rate minimal in comparison with many other laws of Nature; and in the second place, there is no natural process to which they cannot be applied.

W. Nernst