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Questions
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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Solution
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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