Ions with Nonelectrolytes in Solution

The picture that has emerged in this book so far is of ions interacting with a solvent and producing the interesting effects that go under the name solvation. The solvent 

Structure is not the same after an ion has entered it near the ion. Some of the water molecules are wrenched out of the quasi-lattice and appropriated by the ion as part of its primary solvation sheath. Further off, in the secondary solvation sheaths, the ions produce the telltale effects of structure breaking. 

What happens if, in addition to ions and water molecules, molecules of nonelectrolytes are also present in the system Or what will occur if ions are added to a solution already saturated with nonelectrolyte molecules  

Occasionally, however, the ions are deviants and associate preferentially with the nonelectrolyte solute, shunning the water (hydrophobic effects). In the rare instances where these deviants appear, there is a rapid departure of the nonelectrolyte from the parent lattice and the solubility of the former is enhanced rather than deaeased. The phenomenon is called salting in. 

Two aspects of the theory of salting out are considered below. First, the effects of the primary solvation sheath have to be taken into account how the requisition of water by the ions causes the nonelectrolyte s solubihty to decrease. Second, the effects of secondary solvation (interactions outside the solvation sheath) are calculated. The 

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