Choose the correct reason(s) for the stability of the lyophobic colloidal particles.
- (A)Preferential adsorption of ions on their surface from the solution✓ Correct
- (B)Preferential adsorption of solvent on their surface from the solution
- (C)Attraction between different particles having opposite charges on their surface
- (D)Potential difference between the fixed layer and the diffused layer of opposite charges around the colloidal particles✓ Correct
Answer: (A), (D)
Solution
Lyophobic colloids (solvent-hating) are inherently unstable and require stabilization. They are stabilized by: (A) Preferential adsorption of ions from solution onto their surface, creating a charged layer. (D) The resulting potential difference between the fixed layer (Stern layer) and the diffused layer (Gouy-Chapman layer) of opposite charges creates an electrical double layer that prevents coagulation through electrostatic repulsion. Option (B) describes lyophilic colloids. Option (C) would lead to coagulation, not stability.
JEE Advanced · 2012 · 08 Apr 2012 · Paper 1 · One or more correct options