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Questions
What is the reason for the stability of colloidal sols?
Write the main reason for the stability of colloidal sols.
Solution 1
Reasons for the stability of colloidal sols:
a. Coagulation of the colloidal sol is prevented because of the presence of equal and similar charges on the colloidal particles.
b. Colloidal particles are covered by a sheath of liquid in which they are extensively solvated because of which they acquire stability.
Solution 2
There are two main reasons for the stability of colloidal sols:
1. Electrostatic stabilisation: Presence of equal and similar charges on the colloidal particles prevents coagulation of the colloidal sol.
2. Solvation: Colloidal particles are covered by a sheath of liquid in which they are extensively solvated, thereby providing stability.
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