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 Manganese compounds where manganese is in oxidation state +7, which are mostly restricted to the unstable oxide MnO, compounds of the intensely purple permanganate anion MnO, and a few oxyhalides (MnOF and MnOCl), are powerful oxidizing agents. Compounds with oxidation states +5 (blue) and +6 (green) are strong oxidizing agents and are vulnerable to disproportionation. The most stable oxidation state for manganese is +2, which has a pale pink color, and many manganese(II) compounds are known, such as manganese(II) sulfate (MnSO) and manganese(II) chloride (MnCl). This oxidation state is also seen in the mineral rhodochrosite (manganese(II) carbonate). Manganese(II) most commonly