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Questions
Explain what is observed when an electrolyte NaCl is added to hydrated ferric oxide sol.
What happens when a solution of NaCl is added to a ferric hydroxide sol? Explain.
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Solution
When NaCl is added to ferric oxide sol, it dissociates to give Na+ and Cl− ions. Particles of ferric oxide sol are positively charged. Thus, they get coagulated in the presence of negatively charged Cl− ions.
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