Jump to content

Photo
- - - - -

Iron (II) Hydroxide


  • Please log in to reply
6 replies to this topic

#1 Dasherman

Dasherman

    Megabyte

  • Members
  • 496 posts
  • LocationAzeroth and Sanctuary, simultaneously by using quantum powers

Posted 14 February 2013 - 09:06 AM

This is a bit of a homework question, but I genuinely wonder.
Iron(II)-hydroxide reacts with oxygen and water to form something else, but what's that something else?
I'm torn between either Fe2O3 and Fe(OH)3, but I'm not sure at all, I am still in high school :(
Any chemistry-fans who could tell me what Iron(II)-hydroxide becomes when reacting with oxygen and water?
Quis custodiet ipsos custodes?
(//MihiPotestasSit\\)

#2 Affray

Affray

    Knower of things

  • Members
  • 5,753 posts
  • LocationThe Great White North

Posted 14 February 2013 - 09:18 AM

Molten iron even reacts with water to form an aqueous solution of Fe2+ ions and H2 gas.

Fe(l) + 2 H2O(l) Posted Image Fe2+(aq) + 2 OH-(aq) + H2(g)

At room temperature, however, all three of these reactions are so slow they can be ignored.
Iron only corrodes at room temperature in the presence of both oxygen and water. In the course of this reaction, the iron is oxidized to give a hydrated form of iron(II) oxide.

2 Fe(s) + O2(aq) + 2 H2O(l) Posted Image 2 FeO · H2O(s)

Because this compound has the same empirical formula as Fe(OH)2, it is often mistakenly called iron(II), or ferrous, hydroxide. The FeO · H2O formed in this reaction is further oxidized by O2 dissolved in water to give a hydrated form of iron(III), or ferric, oxide.

4 FeO · H2O(s) + O2(aq) + 2 H2O(l) Posted Image 2 Fe2O3 · 3 H2O(s)

To further complicate matters, FeO · H2O formed at the metal surface combines with Fe2O3 · 3 H2O to give a hydrated form of magnetic iron oxide (Fe3O4).

FeO · H2O(s) + Fe2O3 Posted Image 3 H2O(s) Fe3O4 · n H2O(s)

Because these reactions only occur in the presence of both water and oxygen, cars tend to rust where water collects. Furthermore, because the simplest way of preventing iron from rusting is to coat the metal so that it doesn't come in contact with water, cars were originally painted for only one reason Posted Image to slow down the formation of rust.

It is perfectly acceptable to fear and admire a being you could not possibly understand.


#3 Dasherman

Dasherman

    Megabyte

  • Members
  • 496 posts
  • LocationAzeroth and Sanctuary, simultaneously by using quantum powers

Posted 14 February 2013 - 10:04 AM

The Iron(II)-hydroxide was formed by pouring an Iron-sulfate solution into a natrium-hydroxide solution. It was very clearly green, a dark, yucky, spinach kind of green. Because it was not molten iron, the first option is ruled out. After filtering the solution, the filter had something brown/yellowish on it. Would that be the hydrated FeO or Fe2O3 salts?
Quis custodiet ipsos custodes?
(//MihiPotestasSit\\)

#4 Affray

Affray

    Knower of things

  • Members
  • 5,753 posts
  • LocationThe Great White North

Posted 14 February 2013 - 11:00 AM

The Iron(II)-hydroxide was formed by pouring an Iron-sulfate solution into a natrium-hydroxide solution. It was very clearly green, a dark, yucky, spinach kind of green. Because it was not molten iron, the first option is ruled out. After filtering the solution, the filter had something brown/yellowish on it. Would that be the hydrated FeO or Fe2O3 salts?


I'm not sure on that one.
It has been a while since I took any sort of chemistry class.

It is perfectly acceptable to fear and admire a being you could not possibly understand.


#5 Dasherman

Dasherman

    Megabyte

  • Members
  • 496 posts
  • LocationAzeroth and Sanctuary, simultaneously by using quantum powers

Posted 14 February 2013 - 11:34 AM

Well, thanks for your help anyway:)
Quis custodiet ipsos custodes?
(//MihiPotestasSit\\)

#6 SIlhouette

SIlhouette

    Megabyte

  • Members
  • 383 posts

Posted 15 February 2013 - 01:40 AM

Does it go a murky brown if left standing?

#7 Dasherman

Dasherman

    Megabyte

  • Members
  • 496 posts
  • LocationAzeroth and Sanctuary, simultaneously by using quantum powers

Posted 15 February 2013 - 02:46 AM

I'm not sure, it was during class, so I haven't left it standing.
Quis custodiet ipsos custodes?
(//MihiPotestasSit\\)