Volumetric properties of dilute aqueous solutions of cobalt-amine-type salts. Part I. Densities at 25�C

The densities of dilute aqueous solutions of [CoL3]X3 [L=1,2-diaminoethane(en), 1,2-diaminopropane(pn), 1,3-diaminopropane(tn) X=Cl−, Br− and (ClO4)−] have been measured at 25°C from 0 to 5×10−2m. The apparent molar volumes were calculated and extrapolated to infinite dilution. Ion-solvent interactions were detected from the change of the ionic partial molar volumes with concentration. These interactions depend both on the properties of the ion (polarization charge density at the surface, hydrophobic groups, etc.) and the characteristics and structure of the solvent.