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.

CAS number20427-59-2
EC number243-815-9
Index number029-021-00-3

Other names for Copper dihydroxide

  • copper(II) hydroxide

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 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.

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

03 · 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.

Property Value Conditions Source
Melting point Decomposes at melting point, with loss of water. decomposes HSDB
Density 3.37 g/cm³ HSDB
3.368 g/cm³ at 25 °C DOE PAC
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.

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