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 dihydroxide

Copper dihydroxide is a blue to blue green gel or light blue crystalline powder.

CAS 20427-59-2 Danger

01 · Identification

What Copper dihydroxide is

Copper dihydroxide is a blue to blue green gel or light blue crystalline powder. It is soluble in water.

Under the GHS it carries the signal word Danger.

02 · Identifiers

Copper dihydroxide identifiers and molecular data

Copper dihydroxide CAS number and EC number

CAS number20427-59-2
EC number243-815-9
Index number (CLP Annex VI)029-021-00-3

Other names for Copper dihydroxide

  • copper(II) hydroxide

03 · GHS classification

Copper dihydroxide hazard classification

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

Copper dihydroxide pictograms and signal word

Signal wordDanger

Copper dihydroxide hazard class and category

GHS hazard classes Copper dihydroxide 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 1 or 2 H330 GHS06
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

Where two values are shown with “or”, the hazard statement is shared by more than one category or by more than one class, and the code alone does not say which. H272, for example, belongs to oxidising liquids and to oxidising solids — the physical state decides. The binding answer for a specific entry is in the CLP Annex VI table itself.

Copper dihydroxide hazard statements (H-codes)

Hazard statements assigned to Copper dihydroxide
CodeHazard statement
H330 Fatal 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 dihydroxide. 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 dihydroxide

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 dihydroxide 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 dihydroxide precautionary statements

CLP Annex VI assigns 14 precautionary statements to Copper dihydroxide. 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 dihydroxide 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 меден дихидроксид меден(II) хидроксид
Spanish español Dihidróxido de cobre hidróxido de cobre (II)
Czech čeština hydroxid měďnatý
Danish dansk kobberdihydroxid kobber(II)hydroxid
German Deutsch Kupferdihydroxid Kupfer(II)-hydroxid
Estonian eesti vaskdihüdroksiid vask(II)hüdroksiid
Greek ελληνικά διυδροξείδιο του χαλκού υδροξείδιο του χαλκού (II)
English English copper dihydroxide copper(II) hydroxide
French français dihydroxyde de cuivre hydroxyde de cuivre(II)
Croatian hrvatski bakrov dihidroksid bakar(II) hidroksid
Italian italiano diidrossido di rame idrossido di rame (II)
Latvian latviešu vara dihidroksīds vara(II) hidroksīds
Lithuanian lietuvių vario dihidroksidas vario (II) hidroksidas
Hungarian magyar réz(II)-dihidroxid réz(II)-hidroxid
Maltese Malti diidrossidu tar-ram idrossidu tar-ram(II)
Dutch Nederlands koperdihydroxide koper(II)hydroxide
Polish polski diwodorotlenek miedzi wodorotlenek miedzi(II)
Portuguese português di-hidróxido de cobre hidróxido de cobre (II)
Romanian română dihidroxid de cupru hidroxid de cupru (II)
Slovak slovenčina hydroxid meďnatý, hydroxid meďnatý (II)
Slovenian slovenščina bakrov dihidroksid bakrov (II) hidroksid
Finnish suomi kuparidihydroksidi kupari(II)hydroksidi
Swedish svenska koppardihydroxid koppar(II)hydroxid

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 dihydroxide GHS label elements

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

GHS06 Skull and crossbones pictogramGHS05 Corrosion pictogramGHS09 Environment pictogram

Danger

Copper dihydroxide

  • Fatal 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 dihydroxide in the GHS label constructor →

07 · Health hazards

Copper dihydroxide health hazards and exposure limits

Copper dihydroxide hazard summary

Toxic after ingestion or inhalation; [Hawley] A skin, eye, and respiratory tract irritant; [MSDSonline] 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] See Copper.

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

Copper dihydroxide occupational exposure limits

US occupational exposure limits reported for Copper dihydroxide. 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 dihydroxide 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 dihydroxide melting point

Property Value Conditions Source
Melting point Decomposes at melting point, with loss of water. decomposes HSDB

Copper dihydroxide density

Property Value Conditions Source
Density 3.37 g/cm³ HSDB
3.368 g/cm³ at 25 °C DOE PAC

Copper dihydroxide solubility

Property Value Conditions Source
Solubility Sol in acids, ammonium hydroxide; sol in concn alkali when freshly precipitated. HSDB
Soluble in acid solutions, concentrated alkaline solutions HSDB
Soluble in ammonium hydroxide HSDB

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

09 · Questions

Copper dihydroxide — frequently asked questions

What is the CAS number of Copper dihydroxide?

The CAS number of Copper dihydroxide is 20427-59-2. Its EC number is 243-815-9.

What does a Copper dihydroxide label have to show?

Under CLP Annex VI the label for Copper dihydroxide carries the pictograms Skull and crossbones, Corrosion and Environment and the signal word is Danger.

Is Copper dihydroxide flammable?

CLP Annex VI assigns Copper dihydroxide 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 dihydroxide a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for Copper dihydroxide. 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 dihydroxide?

The US occupational exposure limit reported for Copper dihydroxide 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 melting point of Copper dihydroxide?

The melting point reported for Copper dihydroxide is Decomposes at melting point, with loss of water., decomposes (HSDB).

Nearby

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