| Property | Lyophilic | Lyophobic |
|---|---|---|
| Meaning | Solvent-loving | Solvent-hating |
| Interaction with solvent | Strong (solvation shell around particles) | Weak (little interaction) |
| Preparation | Simple dissolving/dispersing | Special methods (chemical, Bredig's arc) |
| Reversibility | Reversible — re-disperses on adding solvent | Irreversible — cannot re-disperse after coagulation |
| Stability | Highly stable (self-stabilizing by solvation shell) | Less stable (stabilized only by surface charge) |
| Viscosity | Higher than dispersion medium | Similar to dispersion medium |
| Electrolyte needed for coagulation | Large amount (must first dehydrate, then neutralize charge) | Small amount (only needs to neutralize charge) |
| Surface tension | Lower than dispersion medium | Similar to dispersion medium |
| Tyndall effect | Less pronounced (particles may be smaller) | More pronounced |
| Examples | Starch, gelatin, gum arabic, proteins, rubber | Gold sol, sol, Fe(OH)_{3} sol |
Key Insight: The fundamental difference is in particle-solvent interaction. Lyophilic = thick hydration/solvation shell = two barriers to coagulation (steric + charge). Lyophobic = no solvation shell = only one barrier (charge). Remove the charge → lyophobic coagulates.