What is the difference between lyophobic sol and lyophilic sol?
Lyophobic sols: Substances like metals, their sulphides, etc.,
when simply mixed with the dispersion medium do not form
the colloidal sol. Their colloidal sols can only be prepared
by specific methods. They are not much hydrated and are
irreversible in nature. They are called extrinsic colloids.
Lyophilic sols: Liquid loving colloids in which there is affinity
between disperse phase and dispersion medium.
Example: Starch sol, Gum sol, Gelatine sol.