Question

Colloidal particles in a sol can be coagulated by :

• A. heating
• B. adding an electrolyte
• C. adding oppositely charged sol
• D. any of the above methods

Answer 1

The correct option is D any of the above methods

Stability of the lyophobic sols is due to presence of charge on colloidal particles. If charge is removed, particles come together and settle down. Spontaneous destabilization of solution is ageing and destabilization of solution by artificial means is called coagulation.
Methods of coagulation are as follows:
1. Boiling
2. Dialysis
3. Addition of electrolytes
4. Mixing two oppositley charged sols
5. Electrophoresis