Effect of N-acetylglycine on volumetric and acoustic behaviour of aqueous tetrabutylammonium iodide solutions at different temperatures

• New experimental densities and ultrasonic speeds of N-acetylglycine in aqueous TBAI solutions.
• Interactions increase with increase in the concentration of N-acetylglycine in aqueous TBAI solutions.
• Values VABVAB and KABKAB predict the pairwise interactions between N-acetylglycine and TBAI.
• nHnH values indicates that TBAI has a dehydration effect on N-acetylglycine.

In this work, the experimental densities and ultrasonic speeds of N-acetylglycine in (0.01, 0.02, 0.03 and 0.04) mol·kg−1 aqueous tetrabutylammonium iodide (TBAI) solutions have been reported at temperatures (288.15, 293.15, 298.15, 303.15 and 308.15) K and at pressures 101 kPa. The different parameters such as apparent molar volume, limiting apparent molar volume, transfer volume, partial molar expansibility have been derived from density data. Experimental values of ultrasonic speeds were used to estimate coefficient of isentropic compression, apparent molar isentropic compression, limiting apparent molar isentropic compression and its transfer value. The pair and triplet interaction coefficients have also been calculated from transfer parameters. All these parameters offer a convenient method to study the intermolecular interactions between the various components of the ternary mixtures. The interactions increase with increase in the concentration of N-acetylglycine in aqueous TBAI solutions. The variation of these parameters with concentration and temperature clearly suggests the role of (C4H9)4N+(C4H9)4N+ on the solute–solvent interactions in aqueous medium.