Manganese(II,III) oxide Manganese(II,III) oxide Manganese(II,III) oxide is the chemical compound with formula MnO. Manganese is present in two oxidation states +2 and +3 and the formula is sometimes written as MnO.MnO. MnO is found in nature as the mineral hausmannite. MnO formed when any manganese oxide is heated in air above 1000 °C. Considerable research has centred on producing nanocrystalline MnO and various syntheses that involve oxidation of Mn or reduction of Mn. MnO has been found to act as a catalyst for a range of reactions e.g. the oxidation of methane and carbon monoxide; the decomposition of NO, the reduction of
Manganese(II) sulfate highly characteristic. Typically, manganese ores are purified by their conversion to manganese(II) sulfate. Treatment of aqueous solutions of the sulfate with sodium carbonate leads to precipitation of manganese carbonate, which can be calcined to give the oxides MnO. In the laboratory, manganese sulfate can be made by treating manganese dioxide with sulfur dioxide: It can also be made by mixing potassium permanganate with sodium bisulfate and hydrogen peroxide. Manganese sulfate is a by-product of various industrially significant oxidations that use manganese dioxide, including the manufacture of hydroquinone and anisaldehyde. Electrolysis of manganese sulfate yields manganese dioxide, which is called EMD