iron(III) oxide-hydroxide

A number of species are dubbed iron(III) oxide-hydroxide. These chemicals are oxide-hydroxides of iron, and may occur in anhydrous (FeO) or hydrated (FeO·nH₂O) forms. The monohydrate (FeO·H₂O) might otherwise be described as iron(III) hydroxide (Fe3), and is also known as hydrated iron oxide or yellow iron oxide.
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