The capability of the MSA-NRTL model to describe heat effects for binary aqueous electrolyte and nonelectrolyte solutions, with a relatively reduced number of parameters, is examined. The thermodynamic properties described include the osmotic coefficient, phi, the apparent relative molar enthalpy, Phi(L), and the apparent molar heat capacity, Phi(CP). The MSA-NRTL model consists of the mean spherical approximation (MSA) for the long-range electrostatic contribution to the Gibbs energy (for ionic solutions) and a local composition model, the non-random two-liquid (NRTL) model for the short-range contribution. (c) 2007 Elsevier B.V. All rights reserved.