Conduction of current through a water solution of electrolyte has been studied by Savante Arrhenius. He studied in detail that the presence of ions is responsible for the conduction of electricity. So, in 1884 Arrhenius put forward his theory of ionization. This theory is also called the theory of electrolytic dissociation.

Arrhenius's Theory of Ionisation

Arrhenius's theory of ionization states that:
  • When a neutral electrolyte is dissolved in the water, it is splitter into two different ions. So, the process of ion formation is called ionization. Two ions are formed cations (positively charged) and anions (negatively charged).
  • The ions present in the solution are in the process of equilibrium. The neutral molecule splits to form ions and these ions unite to form a neutral molecule.
AB ⇌ A+ + B-
  • The charged ions are free to move through the solution to oppositely charged electrodes. This means to say that ions that are dissociated move toward their respective poles or electrodes.
  • The electrical conductivity of an electrolyte depends upon the number of ions present in the solution. So, the dissociation of any neutral molecule determines its strength of it. The degree of dissociation determines whether it is a strong or weak electrolyte.