The structure of water and electrolyte solutions.

Abstract

Intermolecular forces tend to organize water molecules into a tetrahedral lattice, conferring "crystalline" properties on the liquid. The simple ions, such as Na + , K + , and Cl - , have dimensions which are of the same order as the water molecule. Therefore, in aqueous solution, ions can substitute for water molecules in the water lattice. However, because the force between ion and water molecule differs from the force between 2 water molecules, the properties of the lattice are perturbed by an ion. Transport processes in electrolyte solutions are analyzed in terms of the specific lattice perturbation produced by each ion. This approach is contrasted with the classical hydrodynamic model in which ions in solution are treated as spheres in a continuous fluid. The relevance of ionic transport in aqueous solution to the transport across biologic membranes is briefly discussed.