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PPonte
#7
Mar4-06, 04:16 AM
P: n/a
Quote Quote by Astronuc
Possibly because Na promotes OH-[/url], which would tend to favor Fe3+ - IIRC, it has to do with oxidation potential.
I didn't study yet oxidation power. But even if Na promotes OH- it does not react, since the chemical equation is:

[tex]Fe(SCN)^{2+}[/tex] --> [tex]Fe^{3+}[/tex] + [tex]SCN^-[/tex]

But if you could explain how... Thanks

See - Determination of the Equilibrium Constant
for the Formation of FeSCN2+
It requires some advanced knowledges. Wikipedia gave a hand.

One could add thiocyanic acid to the solution, but that would tend to promote FeSCN2+
Yes. Because to add HSCN is to add SCN-. Correct?