Thermodynamic properties of binary liquid mixtures formed by cyclic ether (1,4-Dioxane) with aromatic hydrocarbons at 298.15K.

The present review aims to explore and analyze the thermodynamic and acoustic behavior of binary liquid mixtures through the study of excess sound velocity (uᴱ) and excess viscosity (ηE). The primary objective is to investigate how molecular interactions, temperature variation, and compositional changes influence these excess properties, which serve as sensitive indicators of non-ideal mixing behavior. Each of the experimental methods specific gravity bottle, Ostwald viscometer and ultrasonic interferometer offers special benefits in terms of precision, throughput, and operational simplicity. These approaches enable a strong knowledge of the thermodynamic behaviour of liquid mixes over a large spectrum of situations. Ultrasonic velocity (u), Density (ρ) and viscosity (η) of the binary liquid mixture of 1,4 –Dioxane (Cyclic ether) and Benzene, Ethyl benzene, Toluene were measured over entire composition range. The measurements were done at constant temperature 298.15 K and at ultrasonic frequency 3Mh.Z. From these data excess values are evaluated. From the properties of these excess values, the nature and strength of molecular interactions in these binary systems are discussed. The non-linear variation of these parameters shows the presence of interaction and their excess values is indicative of interaction between the components molecule in all systems. Results across several binary systems showed consistent correlations between Vᴱ, Hᴱ, and speed of sound, therefore exposing the link between volumetric and energetic changes with molecular packing, hydrogen bonding, and structural fit. Whereas positive values indicate weaker, repulsive, or sterically inhibited interactions. Temperature was found to have a major impact on these characteristics, usually reducing favourable interactions and moving surplus features either towards zero or positive values. Understanding molecular interactions depends on excess thermodynamic and acoustic features, so this study emphasises their relevance and provides essential information for solvent selection, formulation design, and process optimisation in chemical and pharmaceutical sectors.