Manganese(III) oxide Manganese(III) oxide Manganese(III) oxide is a chemical compound with the formula MnO. Heating MnO in air at below 800 °C produces α-MnO (higher temperatures produce MnO). γ-MnO can be produced by oxidation followed by dehydration of manganese(II) hydroxide. Many preparations of nano-crystalline MnO have been reported, for example syntheses involving oxidation of Mn salts or reduction of MnO. Manganese (III) oxide is formed by the redox reaction in an alkaline cell: Manganese (III) oxide MnO must not be confused with MnOOH manganese (III) oxyhydroxide. Contrary to MnO, MnOOH is a compound that decomposes at about 300 °C to form MnO.
Manganese to boost octane rating and reduce engine knocking. The manganese in this unusual organometallic compound is in the +1 oxidation state. Manganese(IV) oxide (manganese dioxide, MnO) is used as a reagent in organic chemistry for the oxidation of benzylic alcohols (where the hydroxyl group is adjacent to an aromatic ring). Manganese dioxide has been used since antiquity to oxidize and neutralize the greenish tinge in glass from trace amounts of iron contamination. MnO is also used in the manufacture of oxygen and chlorine and in drying black paints. In some preparations, it is a brown pigment for paint and is