Question

a). State Kohlrausch’s law of independent migration of ions. Write an expression for the molar conductivity of formic acid at infinite dilution according to Kohlrausch’s law.

 b). The molar conductivity of 0.025 mol L^-1 methanoic acid is 46.1 cm²⁺ mol^-1 methanoic acid is 46.1 cm² mol^-1 . 

c). calculate its degree of dissociation and dissociation constant.

Given λ₀ (H⁺) = 349.6 s cm² mol^-1 and λ₀(HCOO-) = 54.6 s cm² mol^-1 .

Answer 1

Kohlrausch law states that limiting molar conductivity of an electrolyte can be represented as sum of the individual contributions of the anion and cation of the electrolyte.

Λ_om( HCOOH) = λ_om HCOO^- + λ_om H⁺