problems with equation

annie · Post by **annie** » Tue Feb 13, 2007 7:55 am

currently doing an A-level chemistry investigation(coursework) and i'd really appreciate some help with working out the equation between iron(II)oxalate and potassium manganate. i have the half equations for the reaction.I have a work sheet that says 6 moles of MnO₄- react with 5 moles of the fe2(C₂O₄)₂, the only problem is, when i combine the half equations i don't get this molar ratio- i get 4:5. might it have something to do with the complex that Fe(II) forms with the oxalate??
thanks v. much.

vhpk · Post by **vhpk** » Tue Feb 13, 2007 7:19 pm

5Fe₂(C₂O₄)₂ + 4KMnO₄ + 16H₂SO₄ --> 10FeSO₄ + 2K₂SO₄ + 4MnSO₄ + 20CO₂ + 16H₂O
Is that right

annie · Post by **annie** » Wed Feb 14, 2007 4:28 am

unfortunately - i don't think so!

you've still got a molar ratio 4:5 (KMnO₄: Fe...) but thanks for trying anyway!

annie · Post by **annie** » Wed Feb 14, 2007 4:39 am

problem solved- i misread the formula for the iron oxalate!!! what an idiot!

Vitalii · Post by **Vitalii** » Wed Feb 14, 2007 8:05 pm

annie wrote:problem solved- i misread the formula for the iron oxalate!!! what an idiot!

I just was about to answer that

Anyway:
5 Fe₂(C₂O₄)₃ + 6 KMnO₄ + 24 H₂SO₄ = 5 Fe₂(SO₄)₃ + 3 K₂SO₄ + 6 MnSO₄ + 30 CO₂ + 24H₂O