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प्रश्न
Explain what is observed when an electric current is passed through a colloidal sol?
What is observed when an electric current is passed through a colloidal solution?
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उत्तर
The colloidal particles are charged and carry either a positive or negative charge. The dispersion medium carries an equal and opposite charge. This makes the whole system neutral. Under the influence of an electric current, the colloidal particles move towards the oppositely charged electrode. When they come in contact with the electrode, they lose their charge and coagulate.
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| Column I | Column II |
| (i) Dispersion medium moves in an electric field | (a) Osmosis |
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(b) Electrophoresis |
| (iii) Movement of charged colloidal particles under the influence of applied electric potential towards oppositely charged electrodes |
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