Ultrasonic study of ion-solvent interactions in aqueous and non-aqueous solutions of transition and inner transition metal ions

Abstract

Ultrasonic velocities(<i>u</i>) and densities(ρ) of aqueous and dimethyl sulphoxide(DMSO) solutions of manganous(II) sulphate cobalt(II) chloride, nickel(II) sulphate, ferrous sulphate, copper(II) sulphate, zinc(II) sulphate, lanthanum(III) nitrate, cerium(IV) nitrate, uranyl nitrate and thorium(IV) nitrate in a wide range of concentrations at a temperature 303K have been measured. Acoustical parameters, such as, adiabatic compressibility (<img src='/image/spc_char/beta.gif' border=0>), free length (L_f) and solvation number(<i>S</i>_n) are computed to assess the ion-solvent interaction in these solutions . It is found that the ion-solvent interactions depend on concentration, ionic size and nature of metal ion. The transition and inner transition metal ions behave as structure breaker for the associated clusters of water molecules, especially in dilute solution, as evidenced from the trend in the solvation number with molarity. It is also found that the strength of ion-dipole interaction in aqueous solution of the metal ion is also dependent on concentration.