Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Copper oxide (CuO)

Copper oxide (CuO) is black to brownish-black amorphous or crystalline powder or granules.

CAS 1317-38-0 CuO 79.55 g/mol Warning

01 · Identification

What Copper oxide (CuO) is

Copper oxide (CuO) is black to brownish-black amorphous or crystalline powder or granules. Its molecular formula is CuO and its molecular weight is 79.55 g/mol. It boils at 1026 °C, melts at 1326 °C, is soluble in water.

Under the GHS it carries the signal word Warning.

CAS number1317-38-0
EC number215-269-1
Index number029-016-00-6
Molecular formulaCuO
Molecular weight79.55 g/mol

Other names for Copper oxide (CuO)

  • copper(II) oxide

02 · GHS classification

Hazards and label elements

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Signal wordWarning
Hazard statements assigned to Copper oxide (CuO)
CodeHazard statement
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P273, P391, P501

03 · Physical and chemical properties

Copper oxide (CuO) properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Property Value Conditions Source
Boiling point 1026 °C (1878.8 °F) decomp HSDB
Decomposes decomposes NIOSH
Decomposes at 1026 decomposes DrugBank
Melting point 1326 °C (2418.8 °F) HSDB
1227 °C (2240.6 °F) DOE PAC
1026 °C (1879 °F) decomposes NIOSH
Density 6.4 g/cm³ CuO NIOSH
6.4 g/cm³ at 25 °C DOE PAC
6.315 g/cm³ at 14 °C HSDB
Solubility Practically insol in water, alc; sol in dilute acids, alkali cyanides, ammonium carbonate soln; slowly sol in ammonia HSDB
SOL IN AMMONIUM CHLORIDE, POTASSIUM CYANIDE HSDB
Soluble in acids; difficultly soluble in water HSDB
Vapor pressure 0 mmHg approx NIOSH
Lower explosive limit (LEL) Explodes when heated with powdered aluminum; anilinium perchlorate; hydrogen; magnesium; and phthalic anhydride. HSDB
CuO: Noncombustible Solid NIOSH

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Handling and storage

Storing and handling Copper oxide (CuO)

Incompatible materials

BORON REACTS VIOLENTLY WITH CUPRIC OXIDE AFTER WARMING, MELTING GLASS TUBING.

Source: Hazardous Substances Data Bank (HSDB)

Planning storage for a mix of chemicals? Check Copper oxide (CuO) in the storage compatibility matrix →

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