Manganese(II,III) oxide

Manganese(II,III) oxide
Names
	IUPAC name manganese(II) dimanganese(III) oxide
	Other names Manganese tetroxide; Manganese oxide; Manganomanganic oxide; Trimanganese tetraoxide; Trimanganese tetroxide;
Identifiers
CAS Number	1317-35-7 ;
3D model (JSmol)	Interactive image;
ChemSpider	34986713;
ECHA InfoCard	100.013.879
EC Number	215-266-5;
PubChem CID	90479253;
RTECS number	OP0895000;
UNII	70N6PQL9JS ;
CompTox Dashboard (EPA)	DTXSID9051660 ;
	InChI InChI=1S/3Mn.4O Key: GVNFAUMGUISVJW-UHFFFAOYSA-N;
	SMILES [Mn]=O.O=[Mn]O[Mn]=O;
Properties
Chemical formula	Mn3O4; MnO·Mn2O3
Molar mass	228.812 g/mol
Appearance	brownish-black powder
Density	4.86 g/cm3
Melting point	1,567 °C (2,853 °F; 1,840 K)
Boiling point	2,847 °C (5,157 °F; 3,120 K)
Solubility in water	insoluble
Solubility	soluble in HCl
Magnetic susceptibility (χ)	+12,400·10−6 cm3/mol
Structure
Crystal structure	Spinel (tetragonal), tI28
Space group	I41/amd, No. 141
Hazards
	GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H315, H319, H335, H361
Precautionary statements	P203, P261, P264, P264+P265, P271, P280, P302+P352, P304+P340, P305+P351+P338, P318, P319, P321, P332+P317, P337+P317, P362+P364, P403+P233, P405, P501
	NIOSH (US health exposure limits):
PEL (Permissible)	C 5 mg/m3
REL (Recommended)	None established
IDLH (Immediate danger)	N.D.
Thermochemistry
Std molar; entropy (S⦵298)	149 J·mol−1·K−1
Std enthalpy of; formation (ΔfH⦵298)	−1387 kJ·mol−1
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Manganese(II,III) oxide is the manganese oxide with the chemical compound with formula Mn₃O₄. Manganese is present in two oxidation states, +2 and +3, and the formula is sometimes written as MnO·Mn₂O₃. Mn₃O₄ is found in nature as the mineral hausmannite.