What are lyophilic and lyophobic sols?Give one example of each type ? Why is hydrophobic sol easily coagulated ?

Explanation

The stability of hydrophobic sol is only due to the presence of charge on the colloidal particles. If charge is removed, e.g., by addition of suitable electrolyres, the particles will come nearer to each other to from aggregate, i.e., they will coagulate and settle down. On the other hand, teh stability of hydrophilic sol is due to charge as well as solvation of the colloidal particles. Both the factors have to be removed to bring about their cagulation.