Thermodynamic properties of the aqueous solution of ethoxyethanol atT=298.15 K

Abstract

The excess enthalpy and heat capacity of the mixture of ethoxyethanol and water were measured atT=298.15 K andT=303.15 K, the density was measured atT=(293.15, 298.15, and 303.15) K, and the speed of sound was measured atT=298.15 K. Excess volume, isentropic and isothermal compressibilities, isochoric heat capacity, and excess thermal expansion factor were estimated from the density and speed of sound measurements. The excess isobaric heat capacity and excess thermal expansion factor were positive and large, especially in the water-rich region. The curve of the former has an anomalous shoulder in the water-rich region. The other properties were negative and large, suggesting that the hydrogen bonds formed in the mixture are more stable than those in the pure states. The looser hydrogen bonds in the mixture compared to those in the highly structured hydrogen bond network in pure water reduce the volume and become less compressible.