Conductance of selected alkali metal salts in aqueous binary mixtures of 2-methoxyethanol at 25 degrees C

Precise conductance measurements have been performed for lithium perchlorat e, lithium tetrafluoroborate, lithium hexafluoroarsenate, sodium perchlorat e, and sodium tetraphenylborate in 2-methoxyethanol-water mixtures at four different mole fractions, i.e., 0.056, 0.136, 0.262, and 0.486 of 2-methoxy ethanol (69.73 greater than or equal to D greater than or equal to 26.55) a t 25 degrees C in the concentration range 0.0004-0.0642 mol-dm(-3). The lim iting molar conductivity Lambda degrees, the association constant K-A, and the association distance R for the solvent mixtures have been evaluated fro m the conductance concentration data using the 1978 Fuoss conductance equat ion. The single-ion conductances have been estimated using the "reference e lectrolyte" tetrabutylammonium tetraphynylborate( Bu4NBPh4). The analysis o f the data indicates that for most salts ion association is appreciable in the solvent mixtures with a mole fraction of the cosolvent of 0.262 or high er. The results have been interpreted in terms of ion-solvent interactions and structural changes in the mixed solvent media.