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Question
What happens when a freshly prepared precipitate of Fe(OH)3 is shaken with a small amount of FeCl3 solution?
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Solution
Peptization takes place forming a positively charged colloidal sol of Fe(OH)3.
Peptization is a process of passing of a precipitate into colloidal particles on adding suitable electrolyte. The electrolyte added is known as the peptizing agent.
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