Tetrabutylammonium Bromide in Dmf-water Systems at Different Temperatures

Ultrasonic velocities in solution of tetrabutylammonium bromide (TBAB) in 10, 20 and 30 %w/w N, N– dimethylformamide (DMF)-water mixtures were measured at 303 K, 308 K and 313 K by using the pulse echo overlap method at a frequency of 3 MHz. The ultrasonic velocity, density, and viscosity were used to calculate the adiabatic compressibility, apparent molal compressibility, apparent molal volume, limiting apparent molal compressibility, limiting apparent molal volume, free volume, internal pressure, solvation number, and viscosity B-coefficient. The observed variation in these parameters with respect to the molality highlights ion-solvent and ion-ion interactions were present, ion-solvent interactions were much pronounced in lower DMF content as well as at lower molalities and ion-ion interactions were very apparent in higher DMF content and at higher salt molality.