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Ferrous sulfate - (Mar/25/2010 )


Does Ferrous sulfate solution (2mg/ml) change the color form transparent to very light brown , when stored at RT?
If it turns the color can we use the solution still?


The reddish colour is the FeIII (ferric) state - rather than the FeII (ferrous) state. I suspect it is not good for what you are using it for, but then you didn't supply any details.


It has oxidized into Fe3+. no point using, solubility is severely affected.

to prevent this by acidifying the solution with sulphuric acid to pH 2 or less.

or use ammonium ferrous sulphate. the Ammonium keep the solution acidic to some extent