Net Effect on Solubility of Influences from Primary and Secondary Solvation

Net Effect on Solubility of Influences from Primary and Secondary Solvation 

The treatment of the effect of secondary solvation has assumed that the primary solvational effects do not exist. In fact, the secondary solvational effects work on the diminished concentration of nonelectrolyte which arises because of the primary solvation. Hence, 

S as written in Eq. (2.154) has taken into account the primary and secondary solvation and can be identified with the solubility of the nonelectrolyte after addition of ions to the solution. Hence, 

There is fair agreement between Eq. (2.158) and experiment. If the nonelectrolyte has a dipole moment less than that of water, it salts out. In the rare cases in which there is a dipole moment in the nonelectrolyte greater than that of water, the nonelectrolyte salts in. 

Salting out has practical implications. It is part of the electrochemistry of everyday industrial life. One reclaims solvents such as ether from aqueous solutions by salting them out with NaCl. Salting out enters into the production of soaps and the manufacture of dyes. Detergents, emulsion polymerization (rubber), and the concentration of antibiotics and vitamins from aqueous solutions all depend in some part of their 

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