2MnO

2MnO is not a standalone chemical species. In chemical notation, “2 MnO” simply denotes two formula units of manganese(II) oxide (MnO) and is used to balance reactions or indicate quantities in a synthesis or equation. There is no widely recognized mineral or compound that is specifically called “2MnO” by itself; MnO remains the single oxide with manganese in the +2 oxidation state.

MnO, manganese(II) oxide, is a binary oxide of manganese. It adopts a rock-salt (cubic) crystal structure with Mn2+ and O2- ions. It is a high-melting, insulating solid and is paramagnetic at room temperature, becoming antiferromagnetic below about 125 K. MnO is typically prepared by reducing MnO2 or MnCO3, or by treating MnO2 with reducing agents such as hydrogen or carbon monoxide at elevated temperatures. In air, MnO is readily oxidized to higher oxides such as Mn3O4 and MnO2.

In practical terms, MnO is commonly used as a starting material for synthesizing other manganese oxides and mixed-oxide systems. It serves as a precursor for catalytic materials, ceramic and glass applications, and certain battery materials, where manganese oxides are valued for their redox properties and structural versatility. MnO’s stability is governed by the redox and oxygen partial pressure of the surrounding environment; under oxidizing conditions it tends to convert to Mn3O4 or MnO2, while under reducing conditions it remains MnO.

See also: manganese oxide, MnO2, Mn2O3, Mn3O4, manganese chemistry.