Question

Which of the following does not involve coagulation

• A. Peptization
• B. Formation of delta region
• C. Treatment of drinking water by potash alum
• D. Clotting of blood by the use of ${\mathrm{FeCl}}_3$

Answer 1

The correct option is A

Peptization

Explanation for correct option

(a) Peptization

• Peptization is the process of transforming precipitate into colloid by mixing it with a suitable electrolyte known as peptizing agent.
• Whereas coagulation is a chemical process in which the unsettlement of non- settleable particles occurs.
• Hence coagulation and peptization are reverse/ opposite processes.

Explanation for incorrect options

(b) Formation of the delta region

• Delta is a place where rivers meet the sea.
• This is responsible because of coagulation.
• River water consists of clay which makes it a colloidal solution.
• Sea water is made up of various types of electrolytes.
• There electrolytes coagulate the colloidal particles.
• Hence, delta region is formed by coagulation process.

(c) Treatment of drinking water by potash alum

• Tiny particles take a lot of time to settle.
• Potash alum acts as coagulant, which means it makes the the particle together to make a clump.
• And large particles will now settle faster.
• Hence, treatment of drinking water by potash alum is a coagulation process

(d) Clotting of blood by the use of ${\mathrm{FeCl}}_3$

• ${\mathrm{Fe}}^{3+}$of ${\mathrm{FeCl}}_3$(ferric chloride) coagulates blood being a negatively charged sol.
• Blood being a colloidal solution, on rubbing ferric chloride, coagulation of blood takes place.
• By this process, bleeding stops.
• Hence clotting of blood by the use of ${\mathrm{FeCl}}_3$ is coagulation process.

Hence option (a) peptization is correct