JAMB - Chemistry (2010 - No. 33)

When iron is exposed to moist air, it gradually rusts. This is due to the formation of?

hydrate iron (III) oxide

anhydrous iron (III) oxide

anhydrous iron (II) oxide

hydrate iron (II) oxide

Rusting is an oxidation reaction. The iron reacts with water and oxygen to form hydrated iron(III) oxide, which we see as rust.