Mechanism of sodium chloride diossolving in water and the process of the solution aging

By the method of Flicker Noise Spectroscopy (FNS) we studied the process of sodium chloride dissolving in water (3.5 wt %) at 294 K on the level of long-range order formation in liquid. It is established that the process of dissolving the salt includes the following steps: formation of instable colloid particles, instable solvate clusters of the salt ion pairs (iSCIP), instable dissolved polymers of globular type, and 12 h later beginning of a new process of formation stable solvate clusters of the salt ion pairs (sSCIP) and stable polymer globules on their basis. Stroke diagrams of the cluster nano-structure and a model of aging the salt solution are presented. Influence of atmospheric pressure on the SCIP average weight is demonstrated. It is concluded that on the SCIP surface there is a porous layer of solvate water with membrane properties. The cluster structure of the 3.5 wt % solution prepared by dissolving the salt is shown to differ from that of the solution obtained by dilution. The solutions long-range order is formed by the nano dispersion of the water solvated salt crystal nuclei. The mechanism of the solution aging is discussed.