This study investigates the thermodynamic, acoustic, and optical properties of liquids to gain essential insights into material behavior. The work concerns on measuring and correlating density, ρ speed of sound u, and refractive index, \({n}_{\text{D}}\) parameters for characterizing binary and ternary mixture of ethylene glycol diacetate (EGDA), dimethyl carbonate (DMC), and N, N-dimethyl formamide (DMF). Measurements were taken across the full composition range at three temperatures (298.15, 308.15, and 318.15 K) under ambient pressure (81.5 kPa). From these data, derived properties such as excess molar volume, \({V}_{\text{m}}^{\text{E}}\) excess partial molar volumes, \({\overline{V} }_{\text{i}}^{\text{E}}\) deviations in speed of sound (∆u), and deviations in refractive index, \({\Delta n}_{\text{D}}\) were calculated. For binary and ternary mixture, the parameters \({V}_{\text{m}}^{\text{E}}\) , ∆u, and \({\Delta n}_{\text{D}}\) were correlated using the Redlich–Kister and Cibulka equations, respectively. The PC-SAFT equation of state successfully predicted the mixtures densities. Analysis of these excess and deviation properties elucidates the mixtures’ intermolecular interactions, molecular size effects, and structural features.
