Vapour pressure study of the deuterium exchange reaction in methanol-ethanol systems: equilibrium constant determination

Abstract

The equilibrium constant of the reaction

                       CH₃OH(1)+C₂H₅OD(1) → CH₃OD(1)+C₂H₅OH(1)

is obtained from vapour pressure measurements on methanol+ethanol systems. The value obtained, 1.03±0.01 at 298 K, is in good agreement with that calculated independently from previously reported vapour pressure studies of water+methanol and water+ethanol systems. Vapour pressures at 298.15 K are reported for the systems CH₃OH+C₂H₅OH, CH₃OH+C₂H₅OD, CH₃OD+C₂H₅OH and CH₃OD+C₂H₅OD. Molar excess Gibbs functions are obtained from these vapour pressures.