Iron (III) oxide
|__ Fe 3+ __ O 2−|
|Surname||Iron (III) oxide|
|Ratio formula||Fe 2 O 3|
red to black crystals
|External identifiers / databases|
|Molar mass||159.70 g mol −1|
5.24 g cm −3
1539 ° C
almost insoluble in water
1.5 mg m −3 (aerosol fraction)
|As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .|
It is possible to obtain red iron oxide by burning iron (III) oxide hydroxide, among other things . During this process, yellow iron oxide is heated to over 200 ° C, with the formation of water vapor.
Meaning and use
Iron (III) oxide is used as a magnetizable material as a recording layer for audio tapes . Iron (III) oxide is also a component of superparamagnetic iron oxide nanoparticles , which are used as contrast media in magnetic resonance tomography and especially in molecular imaging .
- Elemental aluminum reacts with iron (III) oxide to form elemental iron and aluminum (III) oxide .
In the early modern period it was also obtained by distilling iron sulfate (green vitriol) (caput mortuum, head of the dead) and used as red paint.
- Hematite (blood stone) Fe 2 O 3 , trigonal crystal system
- Maghemite ( Maghemite ) Fe 2 O 3 , cubic crystal system
- Iron (II, III) oxide Fe 3 O 4 also: magnetite
- Iron (II) oxide FeO
- Iron (III) oxide hydrate - the hydrate of iron (III) oxide comes e.g. B. as limonite 2Fe 2 O 3 , 3H 2 O or goethite Fe 2 O 3 , H 2 O before.
- Entry on iron oxides. In: Römpp Online . Georg Thieme Verlag, accessed on November 10, 2014.
- Data sheet Iron (III) oxide from Sigma-Aldrich , accessed on March 29, 2011 ( PDF ).
- about DIN 6164 6 to 8 Kurt Wehlte : Materials and techniques of painting . Otto Maier, Ravensburg 1967, ISBN 3-473-48359-1 (previously: ISBN 3-473-61157-3 ) p. 113.
- Heinrich Schönemann: From the history of chemistry: From the vitriols to sulfuric acid