Acidic ferric chloride solution on treatment with excess of potassium ferrocyanide gives a Prussian blue coloured colloidal species. It is:

Question

TestHub · Accepted Answer

If we add ferric chloride over potassium ferrocyanide, it forms a white precipitate that will become blue. The reaction is

${FeCl}_{3} + K_{4} [Fe (CN)_{6}] ⟶ KFe [Fe (CN)_{6}] + 3 KCl$

Being small quantity of ferric chloride, not all potassium is displaced.

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