does precipitation work?
2006-09-04 19:21:02 · 2 answers · asked by Yawny 1 in Science & Mathematics ➔ Chemistry
This question keeps poping up all the time...
You have:
FeCl2 + 2AgNO3 -> Fe(NO3)2 + 2AgCl(s)
but also
Ag(+) + e -> Ag E0=+0.7995 V
Fe(+3) + e -> Fe(+2) E0=+0.771 V
So the reaction
Ag(+) + Fe(+2) -> Fe(+3) + Ag
Has E=0.7995-0.771=0.0285 >0 which means that the reaction will take place spontaneously.
So you could have quite a lot of Fe(III) nitrate forming and also having a mixed salt of nitrate and chloride, since metal Ag will leave the solution and Cl- will co-crystallize with Fe(+3) and NO3(-).
On the other hand the E is not that great and the Ag+ will be removed very well since AgCl has extremely low solubility...
So you will have two competing reactions and probably you will get Fe(NO3)2 but probably as a mixture with Fe(NO3)3; I don't know at what ratio.
Fe+2 in solution oxidates with time to Fe+3 by atmospheric O2 anyway, so you might want to find a better way to get Fe(NO3)2.
Actually Fe(NO3)2 is not stable.
Have a look at http://www.1911encyclopedia.org/Iron
2006-09-04 23:17:34 · answer #1 · answered by bellerophon 6 · 0⤊ 0⤋
i have no idea...i'm blonde
2006-09-05 02:22:50 · answer #2 · answered by lovemykalli 4 · 0⤊ 1⤋