Calculate the degree of hydrolysis:
Problem:
An aqueous solution (0.00784) of aniline hydrochloride had molar conductivity equal to 119.4 ? -1 cm 2 mol -1 which became 103.0 ? -1 cm 2 mol -1 , when a few drops of aniline were added to the solution. Molar conductivity of HCl at the same ionic concentration was found to be 413 ? -1 cm 2 mol -1. Calculate the degree of hydrolysis and hydrolysis constant of aniline hydrochloride.
Answer:
The degree of dissociation of BH+ (aniline H+) B + H+ can be calculated using the expression Λ1 , Λ2 , Λ 3 are molar conductance of salt, salt + base, and acid respectively rearrange
α = Λ1 - Λ2/ Λ3 - Λ4 = (19.4 -103.0) cm 2 ? -1 mol -1/ (413 -103)cm 2 ? -1 mol -1
= 16.4/ 310 = 0.0529
K h = cα 2/1 - α = (0.00784) (0.0529)2 /(1 - 0.05929) = 2.035×10 -5