found: Wikipedia, Aug. 19, 2012(Category: Iron compounds. This is intended for compounds that contain iron in their composition.) Ferric (Ferric refers to iron-containing materials or compounds. In chemistry the term is reserved for iron with an oxidation number of +3, also denoted iron(III) or Fe³⁺. On the other hand, ferrous refers to iron with oxidation number of +2, denoted iron(II) or Fe²⁺.) Iron (Iron forms compounds mainly in the +2 and +3 oxidation states. Traditionally, iron(II) compounds are called ferrous, and iron(III) compounds ferric. Iron also occurs in higher oxidation states, an example being the purple potassium ferrate (K₂FeO₄) which contains iron in its +6 oxidation state. Iron(IV) is a common intermediate in many in biochemical oxidation reactions. Numerous organometallic compounds contain formal oxidation states of +1, 0, -1, or even -2.)
found: Columbia encyclopedia, 6th ed., via Fact monster website, Aug. 19, 2012:iron > compounds (Iron forms such compounds as oxides, hydroxides, halides, acetates, carbonates, sulfides, nitrates, sulfates, and a number of complex ions. It is chemically active and forms two major series of chemical compounds, the bivalent iron (II), or ferrous, compounds and the trivalent iron (III), or ferric, compounds.)
