Physico-chemical studies of sodium tetraphenylborate and tetrabutylammonium tetraphenylborate in pure nitrobenzene and nitromethane and their binaries probed by conductometry, refractometry and FT-IR spectroscopy

Precise measurements on electrical conductances of sodium tetraphenyl borate (NaPh4B) and tetrabutyl ammonium tetraphenyl borate (Bu4NPh4B) in different mass fraction (0.00 to 1.00) of nitromethane (CH3NO2) in nitrobenzene (PhNO2) at 298.15 K have been performed. Limiting molar conductances (Λ0), association constants (KA) and co-sphere diameter (R) for ion-pair formation in the mixed solvent systems have been evaluated using the Fuoss conductance-concentration equation. The FT-IR spectra for the solvents as well as the solute in solvent have also been studied. The results show more association of the ions in PhNO2 than CH3NO2 and results have been interpreted in terms of ion–solvent and solvent–solvent interaction.

► Physico-chemical studies of NaPh4B and Bu4NPh4B in pure PhNO2 and CH3NO2 and their binaries. ► More Λo of NaPh4B than Bu4NPh4B in the pure as well as solvent mixture. ► Λo of both NaPh4B and Bu4NPh4B increases with the increase in CH3NO2 in the solvent mixture.