Question

State and explain Kohlrausch’s law.

What is Kohlrausch’s law?

Answer 1

The molar conductivity at infinite dilution of an electrolyte is equal to the sum of molar conductances of its cations and anions, with each conductance term multiplied by the number of respective ions present in the formula unit of the electrolyte.

If \[\ce{\lambda^{\infty}_{+}}\] and \[\ce{\lambda^{\infty}_{-}}\] respectively represent the molar conductivities of cations and anions of an electrolyte, then according to Kohlrausch's law

\[\ce{\Lambda{^{\infty}_{m}} = v_+ \lambda{^{\infty}_{+}} + v_+ \lambda^{\infty}_{-}}\]

Where, v₊ and v₋ are respectively the number of cations and anions per formula unit of the electrolyte.