# Acidified sodium sulfite in the reduction of iron(III) to iron(II)

Why does sodium sulfite have to be acidified in the reduction of $\ce{Fe^{3+}}$ to $\ce{Fe^{2+}}$?

Does the acid act simply as a catalyst or is it necessary for the reduction process?

• You'd have some problem with reducing precipitate... – Mithoron Jul 23 '17 at 17:09