A lyophilic sol needs a much higher electrolyte concentration to coagulate than a lyophobic sol of similar charge mainly because:

Alyophilic particles are much larger than lyophobic particles
Blyophilic sols are irreversible
Clyophilic particles carry no charge at all
Dthe particles are stabilised by a solvation layer in addition to charge, and both must be disturbed

Answer: D

Lyophilic particles are stabilised both by their charge and by a tightly held solvent layer. Coagulation (salting out) therefore needs large amounts of electrolyte or a dehydrating agent. Lyophilic sols are reversible, and they usually do carry some charge.

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