ABSTRACT
Polysilicates or sols of very small particles are stabilized
by having sufficient alkali in the system. Yates (41) pro-
posed that alkali-stabilized sols are stable not only
against gelling, but also in the thermodynamic sense. He
pointed out that there are thermodynamic factors that
prevent the spontaneous growth of particles or their aggre-
gation and stabilize the high interfacial solid-liquid inter-
face in the silica-water system. The main factor that
counterbalances the free energy change involved in loss
of surface area in the silica-water system is the strong
adsorption of the continuous liquid phase or of stabilizing
counterions or of other adsorbed species at the surface of
the dispersed phase, thus changing the free energy of the
interface.