What is peptization? Explain with example

What is peptization? Explain with example.

Peptization: Peptization may be defined as the process of converting a precipitate into colloidal sol by shaking it with dispersion medium with a small amount of electrolyte. The electrolyte used for this purpose is called peptizing agent. when ferric chloride is added to ferric hydroxide precipitate, the precipitate of hydroxide changes to sol by adsorbing ferric ions. Fe3+ is absorbed on Fe(OH)3 and breaks into colloids.
Black dots represent Fe3+