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

Cobalt sulfide

Cobalt sulfide is a black amorphous powder.

CAS 1317-42-6 Warning

01 · Identification

What Cobalt sulfide is

Cobalt sulfide is a black amorphous powder. It melts at 1117 °C, is practically insoluble in water.

Under the GHS it carries the signal word Warning.

CAS number1317-42-6
EC number215-273-3
Index number027-003-00-X

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 Cobalt sulfide
CodeHazard statement
H317 May cause an allergic skin reaction.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P261, P272, P273, P280, P313, P333, P391, P501

03 · Physical and chemical properties

Cobalt sulfide 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 1117 °C (2042.6 °F) HSDB
1116 °C (2040.8 °F) above this value ICSC
Density 5.45 g/cm³ HSDB
5.5 g/cm³ ICSC
Solubility Insoluble in water HSDB
0.00038 g/100 cc H2O at 18 °C at 18 °C HSDB

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

04 · Source notes

Further notes on Cobalt sulfide

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

Using OECD Guideline 105 (Water Solubility), the water solubility of cobalt monosulfide at 21 to 23 °C and pH 6 varied with loading concentration and dissolution time. Under the conditions of this test, the dissolution of CoS is 103.7 ug/L for a 28-day endpoint (1 mg/L loading), 11362.4 ug/L for a 7-day endpoint (10 mg/L loading) and 7666.8 ug/L for a 7-day endpoint (100 mg/L loading).

Source: HSDB

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