Comparative Ultrasonic and Thermophysical Investigation of Ethylbenzoate + Alcohol Binary Liquid Mixtures

Ultrasonic velocity, density and viscosity measurements provide valuable information regarding molecular interactions and structural effects in liquid mixtures. In the present investigation, ultrasonic velocity (U), density (ρ), viscosity (η) and derived acoustic parameters such as adiabatic compressibility (β_ad), intermolecular free length (L_f), acoustic impedance (Z), internal pressure (π), molar volume (V_m) and enthalpy (H) have been determined for binary liquid mixtures of ethylbenzoate with 2-methyl-1-propanol and 2-butanol over the entire mole fraction range at temperatures of 303.15-318.15 K. Ultrasonic and thermophysical parameters exhibit systematic dependence on composition and temperature, revealing significant deviation from ideal behavior. Excess properties were evaluated to quantify the strength of intermolecular interactions. The comparative analysis indicates stronger interaction effects in the ethylbenzoate + 2-butanol system relative to the branched alcohol system, attributed to molecular geometry and hydrogen bonding efficiency. The results demonstrate that ultrasonic techniques are effective probes for investigating molecular interactions in ester-alcohol mixtures and provide reliable data for thermodynamic modeling and industrial applications.