Question

A solution known to contain acetate ions must be separated. Which reagent will participate acetate ions for a filtration analysis?

Answer 1

Acetate ions reacts with iron (III) ions to form red-brown iron (III) precipitate.

3Fe³⁺ + 9CH₃COO^- + 2H₂O$\to$ [Fe₃(OH)₂(CH₃COO)₆]CH₃COO + 2CH₃COOH

Procedure

Pour 6 drops of solution of acetate ions into a test tube and add 2 drops of solution of iron chloride (III). The solution turns red-brown. Gently heat the tube contents to boiling. On boiling, the solution turns into a red-brown precipitate of basic acetate of iron (III). The mixture can then be filtered.