Iron(II) oxide

Iron(II) oxide is an chemical compound composed of iron in the +2 oxidation state bonded to oxygen atoms. It easily converts to a mixture of iron and iron(II,III) oxide at room temperature. It is stable though when it is very hot. It is a black powder. If it gets hydrated (bonded to extra water molecules), it turns green. The green chemical, named iron(II) hydroxide, gets oxidized by oxygen to a reddish color of iron(III) oxide.

Iron(II) oxide is very rare in nature because of how easily it converts to other iron oxides. Natural samples are called wüstite.

 Related pages 
 Iron(II,III) oxide

Category:Iron compounds
Category:Oxides
Category:Inorganic pigments