Apparent molar volumes and apparent molar heat capacities of aqueous magnesium nitrate, strontium nitrate, and manganese nitrate at temperatures from 278.15 K to 393.15 K and. at the pressure 0.35 MPa

摘要

Apparent molar volumes V-phi and apparent molar heat capacities C-p,C-phi were determined at the pressure 0.35 MPa for aqueous solutions of magnesium nitrate Mg(NO3)(2) at molalities m = (0.02 to 1.0) mol . kg(-1), strontium nitrate Sr(NO3)(2) at m = (0.05 to 3.0) mol . kg(-1), and manganese nitrate Mn(NO3)(2) at m = (0.01 to 0.5) mol . kg(-1). Our V-phi values were calculated from solution densities obtained at T = (278.15 to 368.15) K using a vibrating-tube densimeter, and our C-p,C-phi values were calculated from solution heat capacities obtained at T = (278.15 to 393.15) K using a twin fixed-cell, differential, temperature-scanning calorimeter. Empirical functions of m and T were fitted to our results, and standard state partial molar volumes and heat capacities were obtained over the ranges of T investigated. (c) 2006 Elsevier Ltd. All rights reserved.