Partial molar volumes and thermodynamic properties of alkali metal halides in 10% (w/w) 2-(Ethoxy) ethanol water mixture

Abstract

Apparent molar volumes of alkali metal halides in 10% (W/W) 2-(Ethoxy) ethanol-water mixture were calculated from the measured densities at 303.15K, 308.15K and 313.15K. Using Masson equation the partial molar volumes were obtained which are further divided into ionic components adopting the methods of Conway and Jolicoeur. A comparison of values of ionic partial molar volumes of alkali metal and halide ions with the values reported in pure water indicates a decrease in hydrophobic hydration, which may be due to the addition of co-solvent 2-(Ethoxy) ethanol. The conclusions drawn from viscosity studies confirm that the structure of water is reduced by the breaking of hydrogen bonds in 2-(Ethoxy) ethanol-water mixture. For all the ions,  the values are divided into and . Using the Padova’s equation, the values of alkali metal salts were calculated and further divided into ionic contributions. Calculated dimensions of ions show that the classification of alkali metal halide salts into structure makers and structurebreakers based on the sign of is not valid for the present solvent system.