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 (Cu2O)

Copper oxide (Cu2O) is red-brown cubic crystals.

CAS 1317-39-1 Danger

01 · Identification

What Copper oxide (Cu2O) is

Copper oxide (Cu2O) is red-brown cubic crystals. It boils at 1800 °C, melts at 1235 °C.

Under the GHS it carries the signal word Danger.

CAS number1317-39-1
EC number215-270-7
Index number029-002-00-X

Other names for Copper oxide (Cu2O)

  • dicopper oxide
  • copper (I) 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 wordDanger
Hazard statements assigned to Copper oxide (Cu2O)
CodeHazard statement
H332 Harmful if inhaled.
H302 Harmful if swallowed.
H318 Causes serious eye damage.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P260, P270, P271, P273, P280, P301, P304, P305, P310, P312, P330, P338, P391, P501

03 · Physical and chemical properties

Copper oxide (Cu2O) 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 1800 °C (3272 °F) HSDB
Melting point 1235 °C (2255 °F) HSDB
1232 °C (2249.6 °F) ICSC
Density 6 g/cm³ HSDB
Solubility PRACTICALLY INSOLUBLE IN ORGANIC SOLVENTS; SOL IN DILUTE MINERAL ACIDS, SOLN OF AMMONIA & ITS SALTS. HSDB
Vapor pressure Negligible HSDB
Corrosivity CORRODES ALUMINUM HSDB

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

04 · Source notes

Further notes on Copper oxide (Cu2O)

These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.

Solubility

Crimson, scarlet, vermilion, deep or brownish-red, secondary mineral; adamantine or dull luster; brownish red streak; sol in nitric and concentrated hydrochloric acids; specific gravity: 5.85-6.15; Mohs hardness: 3.5-4 /Cuprite/

Source: HSDB

Soluble in ammonium hydroxide; in hydrochloric acid forming copper(I) chloride which dissolves in excess hydrochloric acid; with dil sulfuric acid or dil nitric acid the cupric salt is formed and half copper is pptd as the metal.

Source: HSDB

05 · Handling and storage

Storing and handling Copper oxide (Cu2O)

Storage conditions

HANDLE WITHOUT SPILLAGE & STORE IN DRY, COOL PLACE.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Heated interaction to produce metallic copper is violent.

Source: Hazardous Substances Data Bank (HSDB)

Planning storage for a mix of chemicals? Check Copper oxide (Cu2O) in the storage compatibility matrix →

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