Sciencemadness Discussion Board

reduction of f3+ to fe2+

estyvenson - 19-8-2010 at 06:53

Can I use sodium sulphite to reduce Fe3+ to Fe2+ ?

12AX7 - 19-8-2010 at 13:56

Yes.

Tim

Ozone - 19-8-2010 at 14:31

Yes...But, it (Fe3+) tends to form up to 35-37 % of a reddish-brown complex with sulfite. This is why it was not used as a reductor in the standard o-phenanthroline assay (which forms the tris-complex with Fe2+) for total iron. Hydroxylamine, while more expensive, and possibly interfeering with wahtever you might need Fe2+ for gives a clean, quantitative reduction. I have the original paper, IIRC, from 1938, Ind. Eng. Chem. analytical Ed. 10, pp. 60, on my work computer and can post it tomorrow if anyone is interested. It is an analytical citation classic.

Cheers,

O3