Density and viscosity of magnesium sulphate in formamide + ethylene glycol mixed solvents

Densities (r) and viscosities (h) of different strengths of magnesium sulphate (MgSO4) in varying proportions of formamide (FA) + ethylene glycol as mixed solvents were measured at room temperature. The experimental values of r and h were used to calculate the values of the apparent molar volume, (phi v), partial molar volume, (phi v°) at infinite dilution, A- and B-coefficients of the Jones–Dole equation and free energies of activation of viscous flow, ( ) 0* 1delta mu and ( ), 0* 2 delta mu per mole of solvent and solute respectively. The behaviour of these parameters suggests strong ion–solvent interactions in these systems and also that MgSO4 acts as structure-maker in FA + ethylene glycol mixed solvents.