State and explain Kohlrausch's law of indendent migration of ions.

Explanation

Kohlrausch.s law of independent migration of ion states that at infine dilution when the dissociation of electrolyte is complete, each ion makes a definite contribution towards the .molar conductivity of electrolyte, irrespective of the nature of the other ion with which it is associated.
Thus the molar conductivity of an electrolyte at infinite dilution can be expressed as the sum of the contributions from its individual ions. If `lambda_(+)^(@) and lambda_(-)^(@)` represent the limiting molar conductivities of cation and anion respectively. Then the limiting molar conductivity of electrolyte at infinite dilution `^^_(m)^(@)` is given by
`^^_(m)^(@)=v_(+)lambda_(+)^(@)+v_(-) lambda_(-)^(@)`
where `v_(+) and v_(-)` represent the number of positive and negative ions furnished by each formula unit of the electrolyte. For example.
(i) once formula unit of NaCl furnishes one `Na^(+)` and one `Cl^(-)` ion, therefore,
`^^_(m)(NaCl)= lambda_(Na^(+))^(@)+lambda_(Cl^(-))^(@)`
(ii) one formula unit of `BaCl_(2)` furnishes one `Ba^(2+)` and two `Cl^(-)` ions, therefore,
`^^_(m)^(@)(BaCl_(2))= lambda_(Ba^(2+))^(@)+2 lambda_(Cl^(-))^(@)`