What happens when sulphur dioxide is passed through an aqueous solution of Fe(III) salt?

SO2 acts as a reducing agent when passed through an aqueous solution containing Fe(III) salt.


It reduces Fe(III) to Fe(II) i.e., ferric ions to ferrous ions.


2Fe3+ + SO2 + 2H2O ⇒ 2Fe2+ + SO42- + 4H+


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