What are lyophilic and lyophobic sols? Give one example of each type. Why are hydrophobic sols easily coagulated ?
Sol of gum, gelatine, starch etc. are lyophilic sols. On the other hand if dispersed phase tends to repel (i.e., dislike or hatred) dispersion medium, the resultant sol is termed as lyophobic sol. Examples are: Sols of metals, metal hydroxides, metal sulphides etc.