MEAN MOLAL ACTIVITY-COEFFICIENTS AND WATER ACTIVITIES OF AQUEOUS RARE-EARTH BROMATE SOLUTIONS AT 25.0 DEGREES-C

The mean moral activities, water activities and osmotic coefficients o f the seven rare earth bromates in aqueous solutions at 25.0 degrees C have been determined from dilute to saturated concentrations. Both th e conductance and isopiestic measurements have been employed to obtain the osmotic coefficients, with subsequent computations of the mean mo ral activity coefficients and water activities. Discussion is made in connection with those values previously obtained, including the chlori des, bromides, nitrates and perchlorates. The behaviour and variations of the activity coefficients and water activities are considered in t erms of the formation of inner-sphere complexes. The effects of the ca tionic radii, as well as the coordination and hydration of the rare ea rth ions, are also considered.