Sciencemadness Discussion Board

Would Fe(OH)3 + Acetic acid give me Iron (III) acetate?

Toluene - 30-11-2013 at 08:55

Hi folks!, this evening I'm planning to experiment something, I have already done a little bit of FeCl3, so I'm thinking about react it with KOH

FeCl3 + 3KOH--> Fe(OH)3 + 3KCl

1) Would be a problem to separate de hydroxide from the potassium chloride?

2 Once I have the Fe(OH)3, can I mix it with pure glacial acetic acid to prepare this complicated molecule?



Could anyone please help me with the stecheometry for this reacction?

Fe(OH)3 + C2H4O2 -->[Fe3O(OAc)6(H2O)3]

Thanks a lot!!

bismuthate - 30-11-2013 at 08:58

1 no Fe(OH)3 is insoluble, but you need a good filter.
2 Yes

Toluene - 30-11-2013 at 09:00

Quote: Originally posted by bismuthate  
1 no Fe(OH)3 is insoluble, but you need a good filter.
2 Yes


Thanks!, so would be a good Idea to add enough water to the mixture Fe(OH)3+KCl in order to dissolve all the KCl and filtrate the Fe(OH)3?

homeIandsecurity - 30-11-2013 at 09:03

no! Because iron acetate isn't soluble in acetic acid...water must dissolve it.

And it is easy to test it...if iron hydroxide dissolves in acetic acid (aq), then it works.

And for this last question...forget about water molecule...3 acetate ions are needed for iron.

bismuthate - 30-11-2013 at 09:03

Absolutely use water. Be warned some iron acetate will go through your filter though.

[Edited on 30-11-2013 by bismuthate]

Toluene - 30-11-2013 at 09:09

By the way, how does Iron acetate (III) look like?

shaheerniazi - 30-11-2013 at 09:10

I once put Iron(III)Oxide in vinegar, and it fized did that produce iron acetate?

homeIandsecurity - 30-11-2013 at 09:17

Maybe you put Iron(2) carbonate. How do you know it is Iron(3) oxide.

shaheerniazi - 30-11-2013 at 09:21

Because I bought it from a paint shop and it said Iron(III)oxide.:)

homeIandsecurity - 30-11-2013 at 09:28

Maybe there was calcium carbonate made by exposure of paint (calcium hydroxide) to atmosphere...it is used as binder...iron is only used as a color.

Toluene - 30-11-2013 at 09:47

By the way, just mixing Fe(OH)3 + acetic acid will give me the desired product iron III acetate? or do I have to put the mixture under reflux?

Metacelsus - 30-11-2013 at 15:58

You will not have to reflux it, especially if the iron hydroxide is freshly precipitated. It may, however, take some time to react.

Also, the structure you drew (and the product of the reaction, according to Wikipedia) is not "true" iron(iii) acetate but a basic iron acetate complex. Remember to adjust your stoichiometry accordingly.

AJKOER - 6-12-2013 at 10:17

I will not try using KOH, or even K2CO3 or a bicarbonate. I would expect the formation of a basic iron salt. As a source, Wikipedia (http://en.wikipedia.org/wiki/Iron(III)_acetate ), on Iron(III) acetate to quote:

"Ferric acetate is the coordination compound more commonly known as "basic iron acetate". With the formula [Fe3O(OAc)6(H2O)3]OAc (OAc is CH3CO2-), it is a salt, composed of the cation [Fe3(μ3-O)(OAc)6(H2O)3]+ and an acetate anion.[4] "

and further:

"Basic iron acetate forms on treating aqueous solutions of iron(III) sources with acetate salts.[6] Solid Iron may be mixed with hydrogen peroxide to form Iron (II and/or III) Hydroxide, which may then be reacted with vinegar/acetic acid or acetate salts."

For an interesting discussion of many Iron salts, I would suggest Atomistry.com (link: http://iron.atomistry.com/ferric_chloride.html and links supplied there to other Iron salts together with comments at http://iron.atomistry.com/iron_salts.html ).


[Edited on 6-12-2013 by AJKOER]

blogfast25 - 7-12-2013 at 11:28

Quote: Originally posted by shaheerniazi  
Because I bought it from a paint shop and it said Iron(III)oxide.:)


Most commercial grades of oxides don't dissolve in acids, not even strong and concentrated ones, easily, sometimes almost not at all. That's because the products have usually been calcinated at high temperature and for prolonged periods, strongly reducing their 'activity' towards acids. Your Fe2O3 won't dissolve even in boiling glacial acetic acid to an appreciable degree.

Freshly precipitated iron (III) hydroxide however will dissolve in it easily, even at RT.

So, from a not to strong solution of a ferric salt, precipitate Fe(OH)3 with a stoichiometric amount of preferably strong ammonia, filter off the Fe(OH)3 and wash it repeatedly with small amounts of water. Note that Fe(OH)3 has an annoying tendency to peptise.

Dissolve the filter cake in a small excess of glacial acetic acid, this is your ferric acetate (basic, I think) solution. To crystallise that salt may prove the hardest bit, though... Most ferric salts are extremely water soluble.

[Edited on 7-12-2013 by blogfast25]