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.

02 · Identifiers

Copper oxide (Cu2O) identifiers and molecular data

Copper oxide (Cu2O) CAS number and EC number

CAS number1317-39-1
EC number215-270-7
Index number (CLP Annex VI)029-002-00-X

Other names for Copper oxide (Cu2O)

  • dicopper oxide
  • copper (I) oxide

03 · GHS classification

Copper oxide (Cu2O) hazard classification

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

Copper oxide (Cu2O) pictograms and signal word

Signal wordDanger

Copper oxide (Cu2O) hazard class and category

GHS hazard classes Copper oxide (Cu2O) falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 4 H302 GHS07
Acute toxicity - inhalation GHS chapter 3.1 Category 4 H332 GHS07
Serious eye damage/eye irritation GHS chapter 3.3 Category 1 H318 GHS05
Hazardous to the aquatic environment - acute GHS chapter 4.1 Category 1 H400 GHS09
Hazardous to the aquatic environment - chronic GHS chapter 4.1 Category 1 H410 GHS09

Copper oxide (Cu2O) hazard statements (H-codes)

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.

This page lists only the codes assigned to Copper oxide (Cu2O). The full reference lives on the hazard statements hub, the precautionary statements hub and the GHS pictograms hub.

Safety Data Sheet

Getting an SDS for Copper oxide (Cu2O)

A Safety Data Sheet is written for a product, not for a substance: the supplier of the grade you actually buy issues it, so two suppliers of Copper oxide (Cu2O) issue two different sheets. That is why there is no single authoritative SDS for a substance to download — what there is, is the job of collecting the sheets for the products you hold and keeping them current as suppliers revise them.

04 · Precautionary statements

Copper oxide (Cu2O) precautionary statements

CLP Annex VI assigns 14 precautionary statements to Copper oxide (Cu2O). They are grouped the way a label groups them: what to do before handling, what to do when something has already happened, how to store it and how to dispose of it.

Disposal

What has to happen to the contents and the empty container.

Reading the notation. is a blank the supplier fills in — not a truncated sentence.· [square brackets] mark a part printed only when it applies.

05 · Names in the regulation

Copper oxide (Cu2O) name in 23 EU languages

CLP Annex VI Part 3 is published in every language edition of the regulation, and the identification column is written out in each of them. Nothing below is translated by us: each line is the name as that edition prints it. Under Art. 18(2) the substance name from Annex VI is a lawful product identifier, so this is the wording to put on a label going to that market — and where the cell lists several designations, any one of them qualifies.

Language Name in CLP Annex VI Part 3
Bulgarian български димеден оксид меден(I) оксид
Spanish español Óxido de dicobre óxido de cobre (I)
Czech čeština oxid měďný
Danish dansk dikobberoxid kobber(I)oxid
German Deutsch Dikupferoxid Kupfer(I)-oxid
Estonian eesti divaskoksiid vask(I)oksiid
Greek ελληνικά οξείδιο του διχαλκού οξείδιο του χαλκού (Ι)
English English dicopper oxide copper (I) oxide
French français oxyde de dicuivre oxyde de cuivre (I)
Croatian hrvatski dibakrov oksid bakar(I) oksid
Italian italiano ossido di dirame ossido di rame (I)
Latvian latviešu divara oksīds vara(I) oksīds
Lithuanian lietuvių divario oksidas vario (I) oksidas
Hungarian magyar diréz-oxid réz (I)-oxid
Maltese Malti ossidu tad-diram ossidu (I) tar-ram
Dutch Nederlands dikoperoxide koper(I)oxide
Polish polski tlenek dimiedzi tlenek miedzi(I)
Portuguese português óxido de dicobre óxido de cobre (I)
Romanian română oxid dicupric oxid de cupru (I)
Slovak slovenčina oxid meďný, oxid meďný
Slovenian slovenščina dibakrov oksid bakrov (I) oksid
Finnish suomi dikuparioksidi kupari(I)oksidi
Swedish svenska dikopparoxid koppar(I)oxid

All 23 language editions of Annex VI carry this entry. Irish is the twenty-fourth official EU language and has no line here for a different reason: no consolidated CLP text has ever been published in Irish, so there is no Irish edition of Annex VI to quote a name from. Source: consolidated CLP, CELEX 02008R1272, language editions. © European Union, https://eur-lex.europa.eu — only the electronic Official Journal of the European Union is authentic.

06 · Label elements

Copper oxide (Cu2O) GHS label elements

Everything CLP Annex VI fixes for Copper oxide (Cu2O), laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS07 Exclamation mark pictogramGHS05 Corrosion pictogramGHS09 Environment pictogram

Danger

Copper oxide (Cu2O)

  • Harmful if inhaled.
  • Harmful if swallowed.
  • Causes serious eye damage.
  • Very toxic to aquatic life.
  • Very toxic to aquatic life with long lasting effects.
  • Do not breathe dust/fume/gas/mist/vapours/spray.
  • Do not eat, drink or smoke when using this product.
  • Use only outdoors or in a well-ventilated area.
  • Avoid release to the environment.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF SWALLOWED:
  • IF INHALED:
  • IF IN EYES:
  • Immediately call a POISON CENTER/doctor/
  • Call a POISON CENTER/doctor/ if you feel unwell.
  • Rinse mouth.
  • Remove contact lenses, if present and easy to do. Continue rinsing.
  • Collect spillage.
  • Dispose of contents/container to

Supplier name, address and telephone number· Product identifier·Nominal quantity

Need this as an actual label? Open Copper oxide (Cu2O) in the GHS label constructor →

07 · Health hazards

Copper oxide (Cu2O) health hazards and exposure limits

Copper oxide (Cu2O) hazard summary

An eye and respiratory tract irritant; Can cause metal fume fever after inhalation and injury to the liver and kidneys after ingestion; [ICSC] Copper-induced metal fume fever is not as common as zinc-induced because of the higher temperature required to produce copper oxide. (Zn mp = 419.5; Cu mp = 1083 deg C.) Acute copper poisoning after ingestion can cause liver injury, methemoglobinemia, and hemolytic anemia. Acute renal failure may result, secondary to massive hemoglobinuria. [Goldfrank, p. 1259] Slowly oxidized by moist air to cupric oxide; [Merck Index] An eye irritant; Toxic by ingestion; [Sigma-Aldrich MSDS] See Copper.

Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

Copper oxide (Cu2O) occupational exposure limits

US occupational exposure limits reported for Copper oxide (Cu2O). PEL is enforceable (OSHA), REL is a recommendation (NIOSH), IDLH is the concentration at which escape becomes impossible without injury.
Limit Value Source
PEL 1.0 [mg/m3], as Cu Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
IDLH 100.0 [mg/m3], as Cu Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

These are United States values. The European Union sets its own indicative and binding limits, and the figure that applies at a given workplace is the one in the local regulation — not the one shown here.

08 · 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.

Copper oxide (Cu2O) boiling point

Property Value Conditions Source
Boiling point 1800 °C (3272 °F) HSDB

Copper oxide (Cu2O) melting point

Property Value Conditions Source
Melting point 1235 °C (2255 °F) HSDB
1232 °C (2249.6 °F) ICSC

Copper oxide (Cu2O) density

Property Value Conditions Source
Density 6 g/cm³ HSDB

Copper oxide (Cu2O) solubility

Property Value Conditions Source
Solubility PRACTICALLY INSOLUBLE IN ORGANIC SOLVENTS; SOL IN DILUTE MINERAL ACIDS, SOLN OF AMMONIA & ITS SALTS. HSDB

Copper oxide (Cu2O) vapor pressure

Property Value Conditions Source
Vapor pressure Negligible HSDB

Copper oxide (Cu2O) corrosivity

Property Value Conditions Source
Corrosivity CORRODES ALUMINUM HSDB

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

09 · 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

10 · Handling and storage

Copper oxide (Cu2O) storage and handling

Copper oxide (Cu2O) safe storage

Separated from aluminium. See Chemical Dangers. Store in an area without drain or sewer access. Store only in original packaging.

Source: ILO-WHO International Chemical Safety Cards (ICSCs)

Copper oxide (Cu2O) storage conditions

HANDLE WITHOUT SPILLAGE & STORE IN DRY, COOL PLACE.

Source: Hazardous Substances Data Bank (HSDB)

Copper oxide (Cu2O) 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 →

11 · Questions

Copper oxide (Cu2O) — frequently asked questions

What is the CAS number of Copper oxide (Cu2O)?

The CAS number of Copper oxide (Cu2O) is 1317-39-1. Its EC number is 215-270-7.

What does a Copper oxide (Cu2O) label have to show?

Under CLP Annex VI the label for Copper oxide (Cu2O) carries the pictograms Exclamation mark, Corrosion and Environment and the signal word is Danger.

Is Copper oxide (Cu2O) flammable?

CLP Annex VI assigns Copper oxide (Cu2O) no flammability hazard class. That is not a statement that it cannot burn: the harmonised list only records the hazards that were assessed for it.

Is Copper oxide (Cu2O) a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for Copper oxide (Cu2O). Annex VI is a list of agreed classifications, not a list of substances found safe, so this is an absence of a classification rather than a clean bill of health.

What is the exposure limit for Copper oxide (Cu2O)?

The US occupational exposure limit reported for Copper oxide (Cu2O) is 1.0 [mg/m3], as Cu (Haz-Map, Information on Hazardous Chemicals and Occupational Diseases). Limits differ by country: the EU sets its own indicative and binding values, and the figure that applies at a given workplace is the one in the local regulation.

What is the boiling point of Copper oxide (Cu2O)?

The boiling point reported for Copper oxide (Cu2O) is 1800 °C (3272 °F) (HSDB).

What is the melting point of Copper oxide (Cu2O)?

The melting point reported for Copper oxide (Cu2O) is 1235 °C (2255 °F) (HSDB).

How should Copper oxide (Cu2O) be stored?

HANDLE WITHOUT SPILLAGE & STORE IN DRY, COOL PLACE. (Hazardous Substances Data Bank (HSDB))

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