Dissociation and kinetic of hydrochloric acid in mixed isomeric alcoholic-aqueous solvents - A conductance study

The effect of water and the effect of time on the conductance behavior of dilute solutions of hydrochloric acid in n-butanol-water and iso-butanol-water mixtures with the alcohol percentages; 97.00%, 97.50%, 98.00%, 98.50%, 99.00%, 99.50%, 99.70% and 99.98% at 298 K are reported. The data were analysed with a computer program for the Lee-Wheaton conductivity equation. The molar conductance (Λ), limiting molar conductance (Λ0), dissociation constants (Kd), and the standard free energy of dissociation (∆G°d) were calculated and discussed. The kinetic of hydrochloric acid conductance was also discussed and the results showed a first order interaction between HCl and the alcoholic solvents. In agreement with previous experiments in alcohol-water mixtures the limiting molar conductance decreases when water is added to the alcohol and then increases again. The results show that, the dissociation constant decreased as the relative permittivity of the solvent decreased.