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प्रश्न
Distinguish between lyophobic and lyophilic sols.
What are the main points of difference between lyophilic and lyophobic sols?
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उत्तर
| Sr. No. | Points | Lyophobic sols | Lyophilic sols |
| 1. | Method of formation | Lyophobic sols are formed only by special methods. | Lyophilic sols are formed easily by direct mixing. |
| 2. | Reversibility | They are irreversible. | They are reversible. |
| 3. | Stability | These are unstable and hence, require traces of stabilizers. | These are self-stabilized. |
| 4. | Effect of electrolytes | The addition of a small amount of electrolytes causes precipitation or coagulation of lyophobic sols. | The addition of a large amount of electrolytes causes precipitation or coagulation of lyophilic sols. |
| 5. | Viscosity | The viscosity of lyophobic sol is nearly the same as the dispersion medium. | The viscosity of lyophilic sol is much higher than that of the dispersion medium. |
| 6. | Surface tension | The surface tension of lyophobic sol is nearly the same as the dispersion medium. | The surface tension of lyophilic sol is lower than that of the dispersion medium. |
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