Question

The origin of charge on colloidal solution is:

• A. frictional rubbing
• B. electron capture during Bredig's arc method
• C. selective adsorption of ion on their surface
• D. due to addition of protective colloids

Answer 1

Answer: (A), (B), (C)

The correct options are
A selective adsorption of ion on their surface
B electron capture during Bredig's arc method
C frictional rubbing

The origin of charge on the sol particles in most cases is due to the preferential adsorption of either positive or negative ions on their surface.
The sol particles acquire electrical charge in any one or more of the following ways:
1. Due to dissociation of the surface molecules.
2. Due to frictional electrification.
3. Due to selective adsorption of ions.
Colloidal solutions prepared by Bredig's Arc method acquire a charge by electron capture.