The ultrasonic velocities, densities, viscosities, and electrical conductivities of aqueous solutions of magnesium nitrate and magnesium acetate have been measured as functions of concentration (0.0145 <= m/mol, kg(-1) <= 6.545) and temperature 273.15 <= T/K <= 323.15. The results are in reasonable agreement with literature data where comparisons are possible. The viscosity and electrical conductivity data are consistent with greater ion association in Mg(OAc)(2) solutions.