(i) Peptization : It is a process of conveting a precipitate into colloidal particles by shaking it with dispersion medium in the presence of a small amount of a suitab le electrolyte.
Lyophobic colloids: Substances like methals and their suphides etc., when simply mixed with dispersion medium do not form the colloidal sol. They are prapared by only special methods. Such substances are called loyphobic and the sol. Formed by them are called lyophobic colloids.
(iii) Dialysis : The process of sparating the particcles of colloids from those of crystalloids by diffusion of mixture through a membren is known as dialysis.
