(i) Mutual coagulation.
(ii) Shong interaction between dispersed phase and dispersion medium or solvated layer.
(iii) CO acts as a poison for catalyst.
Detailed Answer:
(i) Animal hides are colloidal in nature. When a hide which has (+ve)ly charged particles, is soaked in tannin, which contains (-ve)ly charged colloidal particles, mutual coagulation takes place.
This results in the hardening of leather.
(ii) Lyophilic colloids have great affinity for the dispersion medium i.e., dispersed phase particles are solvated to a greater extent in case of lyophilic colloids.
Hence lyophilic sols are relatively more stable than lyophobic sols.
(iii) It is necessary to remove CO when ammonia is prepared by Haber's process because it acts like a poison which reduces the activity of catalyst ion.
