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 Sulfate

Cobalt Sulfate is red to lavender dimorphic, othorhombic crystals and is odorless.

CAS 10124-43-3 CoO4S 155 g/mol Danger

01 · Identification

What Cobalt Sulfate is

Cobalt Sulfate is red to lavender dimorphic, othorhombic crystals and is odorless. Its molecular formula is CoO4S and its molecular weight is 155 g/mol. It melts at 735 °C.

Under the GHS it carries the signal word Danger.

CAS number10124-43-3
EC number233-334-2
Index number027-005-00-0
Molecular formulaCoO4S
Molecular weight155 g/mol

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 Cobalt Sulfate
CodeHazard statement
H350i May cause cancer by inhalation.
H341 Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H360F May damage fertility.
H302 Harmful if swallowed.
H334 May cause allergy or asthma symptoms or breathing difficulties if inhaled.
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: P201, P261, P270, P272, P273, P280, P301, P308, P312, P313, P330, P333, P391, P501

03 · Physical and chemical properties

Cobalt Sulfate 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 735 °C (1355 °F) HSDB
Density 3.71 g/cm³ ICSC
1.948 g/cm³ at 20 °C CAMEO
3.71 g/cm³ at 25 °C HSDB
Solubility Odorless; heat of solution: 23 BTU/lb= 13 cal/g= 0.54X10+5 J/kg; solubility: 35.040 lb/100 lb water at 70 °F at 21.11 °C, Cobaltous sulfate heptahydrate HSDB
In water, 330 g/L at 20 °C at 20 °C HSDB
38.3 g/100 g water at 25 °C at 25 °C HSDB

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

04 · Handling and storage

Storing and handling Cobalt Sulfate

Storage conditions

Separated from strong oxidants.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Reacts as a dust with strong oxidants causing fire and explosion hazard.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

Acidic salts, such as COBALT SULFATE, are generally soluble in water. The resulting solutions contain moderate concentrations of hydrogen ions and have pH's of less than 7.0. They react as acids to neutralize bases. These neutralizations generate heat, but less or far less than is generated by neutralization of inorganic acids, inorganic oxoacids, and carboxylic acid. They usually do not react as either oxidizing agents or reducing agents but such behavior is not impossible. Many of these compounds catalyze organic reactions.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Cobalt Sulfate in the storage compatibility matrix →

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