화학공학소재연구정보센터
Journal of Chemical and Engineering Data, Vol.51, No.5, 1617-1623, 2006
Compressibility studies of binary solutions involving water as a solute in nonaqueous solvents at T = 298.15 K
The experimental measurements of the speed of sound and density in binary solutions of MeOH, EtOH, n-PrOH, n-BuOH, acetonitrile (ACN), dimethylformamide (DMF), tetrahydrofuran (THF), and 1,4-dioxane as solvents and water as the solute in the concentration range of 0.02 mol (.) kg(-1) to 1 mol (.) kg(-1) at T) 298.15 K are reported. The data are used to obtain the isentropic compressibility of solution. The apparent molar volume (phi(V)) and compressibility (phi K) of water at different concentrations are evaluated. The data of limiting volume (phi(0)(V)) and compressibility (phi(0)(K)) and their concentration variation are examined to study the effect due to water-solvent and water-water interactions. It has been observed that there is loss of volume and compressibility of liquid water molecules in transferring them from the pure liquid state to a nonaqueous solvent. An attempt is made to explain the large negative value of phi(0)(K) in alcohols due to H-bonding characteristics of water and alcohol and the effect of the presence of nonpolar groups. The possibilities of the presence of water-centered complexes or participation of water in a chain-like structure along with pressure effects are examined on the basis of concentration variation of the derived properties.