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प्रश्न
What is the reason for the stability of colloidal sols?
Write the main reason for the stability of colloidal sols.
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उत्तर १
Reasons for the stability of colloidal sols:
a. Coagulation of the colloidal sol is prevented because of the presence of equal and similar charges on the colloidal particles.
b. Colloidal particles are covered by a sheath of liquid in which they are extensively solvated because of which they acquire stability.
उत्तर २
There are two main reasons for the stability of colloidal sols:
1. Electrostatic stabilisation: Presence of equal and similar charges on the colloidal particles prevents coagulation of the colloidal sol.
2. Solvation: Colloidal particles are covered by a sheath of liquid in which they are extensively solvated, thereby providing stability.
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संबंधित प्रश्न
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| Column I | Column II |
| (i) Dispersion medium moves in an electric field | (a) Osmosis |
| (ii) Solvent molecules pass through semi permeable membrane towards solvent side |
(b) Electrophoresis |
| (iii) Movement of charged colloidal particles under the influence of applied electric potential towards oppositely charged electrodes |
(c) Electroosmosis |
| (iv) Solvent molecules pass through semi permeable membranes towards solution side |
(d) Reverse osmosis |
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Tyndall effect is observed in
The conditions given below are in the context of observing Tyndall effect in colloidal solutions:
- The diameter of the colloidal particles is comparable to the wavelength of light used.
- The diameter of the colloidal particles is much smaller than the wavelength of light used.
- The diameter of the colloidal particles is much larger than the wavelength of light used.
- The refractive indices of the dispersed phase and the dispersion medium are comparable.
- The dispersed phase has a very different refractive index from the dispersion medium.
Choose the most appropriate conditions from the options given below:
