Manganese(II) oxide that the Mn ions form a face centered cubic magnetic sub-lattice where there are ferromagnetically coupled sheets that are anti-parallel with adjacent sheets. Manganese(II) oxide undergoes the chemical reactions typical of an ionic oxide. Upon treatment with acids, it converts to the corresponding manganese(II) salt and water. Oxidation of manganese(II) oxide gives manganese(III) oxide. MnO occurs in nature as the rare mineral manganosite. Commercially it is prepared by reduction of MnO with hydrogen, carbon monoxide or methane, e.g.: MnO can also be prepared by decarbonation of the carbonate: This calcining process is conducted anaerobically, lest MnO form. An alternative route,
Hazard symbol carry a significant health risk (biohazards), including viral samples and used hypodermic needles (see sharps waste). The biohazard symbol was developed by the Dow Chemical Company in 1966 for their containment products. According to Charles Baldwin, an environmental-health engineer who contributed to its development: "We wanted something that was memorable but meaningless, so we could educate people as to what it means." In an article in "Science" in 1967, the symbol was presented as the new standard for all biological hazards ("biohazards"). The article explained that over 40 symbols were drawn up by Dow artists, and all of the symbols