PHYSICAL CHEMISTRY IN BRIEF

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CHAP. 14: DISPERSION SYSTEMS [CONTENTS] 458

When describing the properties of dispersion systems, we may characterize them using
other criteria too. Lyosols, e.g., may be lyophilic (liquid-loving) or lyophobic (liquid-hating),
according to Freundlich.
Lyophilic sols are such colloid systems which are (almost) stable on any change of the
dispersion environment content (e.g. water evaporation). In the case of lyophobic sols, on the
other hand, the dispersion environment may be removed only to a small extent, otherwise the
sol would irreversibly change to a coagulate. During coagulation the isolated particles of the
dispersion phase unite to form a more extensive macroscopic phase. Glue+water may serve as
an example of a lyophylic system, while a lyophobic system may be represented by a colloid
solution of gold in water.

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