Copper(I) oxide

Copper(I) oxide
	Unit cell
	Crystal packing
Names
	IUPAC name Copper(I) oxide
	Other names Cuprous oxide; Dicopper oxide; Cuprite; Red copper oxide
Identifiers
CAS Number	1317-39-1 ;
3D model (JSmol)	Interactive image; Interactive image;
ChEBI	CHEBI:81908;
ChemSpider	8488659 ;
ECHA InfoCard	100.013.883
EC Number	215-270-7;
KEGG	C18714 ;
PubChem CID	10313194;
RTECS number	GL8050000;
UNII	T8BEA5064F ;
CompTox Dashboard (EPA)	DTXSID0034489 ;
	InChI InChI=1S/2Cu.O/q2+1;-2 Key: KRFJLUBVMFXRPN-UHFFFAOYSA-N ; InChI=1/2Cu.O/rCu2O/c1-3-2 Key: BERDEBHAJNAUOM-YQWGQOGZAF; InChI=1/2Cu.O/q2+1;-2 Key: KRFJLUBVMFXRPN-UHFFFAOYAM;
	SMILES [Cu]O[Cu]; [Cu+].[Cu+].[O-2];
Properties
Chemical formula	Cu2O
Molar mass	143.09 g/mol
Appearance	yellow, red, or brown solid
Density	6.0 g/cm3
Melting point	1,232 °C (2,250 °F; 1,505 K)
Boiling point	1,800 °C (3,270 °F; 2,070 K) decomposes
Solubility in water	Insoluble
Solubility in acid	Soluble
Band gap	2.137 eV
Magnetic susceptibility (χ)	−20×10−6 cm3/mol
Structure
Crystal structure	cubic
Space group	Pn3m, #224
Lattice constant	a = 4.2696
Thermochemistry
Std molar; entropy (S⦵298)	93 J·mol−1·K−1
Std enthalpy of; formation (ΔfH⦵298)	−170 kJ·mol−1
Hazards
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H302, H318, H332, H410
Precautionary statements	P273, P305+P351+P338
NFPA 704 (fire diamond)	2 0 1
	NIOSH (US health exposure limits):
PEL (Permissible)	TWA 1 mg/m3 (as Cu)
REL (Recommended)	TWA 1 mg/m3(as Cu)
IDLH (Immediate danger)	TWA 100 mg/m3 (as Cu)
Safety data sheet (SDS)	SIRI.org
Related compounds
Other anions	Copper(I) sulfide; Copper(II) sulfide; Copper(I) selenide
Other cations	Copper(II) oxide; Silver(I) oxide; Nickel(II) oxide; Zinc oxide
	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

Copper(I) oxide or cuprous oxide is the inorganic compound with the formula Cu₂O. It is one of the principal oxides of copper, the other being copper(II) oxide or cupric oxide (CuO). The compound can appear either yellow or red, depending on the size of the particles. Cuprous oxide is found as the mineral cuprite. It is a component of some antifouling paints, and has other applications including some that exploit its property as a semiconductor.