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.

02 · Identifiers

Cobalt Sulfate identifiers and molecular data

Cobalt Sulfate CAS number and EC number

CAS number10124-43-3
EC number233-334-2
Index number (CLP Annex VI)027-005-00-0

Cobalt Sulfate molecular formula and molecular weight

Molecular formulaCoO4S
Molecular weight155 g/mol

03 · GHS classification

Cobalt Sulfate hazard classification

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

Cobalt Sulfate pictograms and signal word

Signal wordDanger

Cobalt Sulfate hazard class and category

GHS hazard classes Cobalt Sulfate falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 4 H302 GHS07
Respiratory sensitisation GHS chapter 3.4 Category 1 or 1A or 1B H334 GHS08
Skin sensitisation GHS chapter 3.4 Category 1 or 1A or 1B H317 GHS07
Germ cell mutagenicity GHS chapter 3.5 Category 2 H341 GHS08
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.

Cobalt Sulfate hazard statements (H-codes)

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.

This page lists only the codes assigned to Cobalt Sulfate. 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 Cobalt Sulfate

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 Cobalt Sulfate 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

Cobalt Sulfate precautionary statements

CLP Annex VI assigns 14 precautionary statements to Cobalt Sulfate. 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

Cobalt Sulfate 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 кобалтов сулфат
Spanish español Sulfato de cobalto
Czech čeština síran kobaltnatý
Danish dansk cobaltsulfat
German Deutsch Cobaltsulfat
Estonian eesti koobaltsulfaat
Greek ελληνικά θειικό κοβάλτιο
English English cobalt sulfate
French français sulfate de cobalt
Croatian hrvatski kobaltov sulfat
Italian italiano solfato di cobalto
Latvian latviešu kobalta sulfāts
Lithuanian lietuvių kobalto sulfatas
Hungarian magyar kobalt-szulfát
Maltese Malti sulfat tal-kobalt
Dutch Nederlands kobaltsulfaat
Polish polski siarczan kobaltu siarczan(VI) kobaltu
Portuguese português sulfato de cobalto
Romanian română sulfat de cobalt
Slovak slovenčina síran kobaltnatý
Slovenian slovenščina kobaltov sulfat
Finnish suomi kobolttisulfaatti
Swedish svenska koboltsulfat

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

Cobalt Sulfate GHS label elements

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

GHS08 Health hazard pictogramGHS07 Exclamation mark pictogramGHS09 Environment pictogram

Danger

Cobalt Sulfate

  • May cause cancer by inhalation.
  • Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
  • May damage fertility.
  • Harmful if swallowed.
  • May cause allergy or asthma symptoms or breathing difficulties if inhaled.
  • May cause an allergic skin reaction.
  • Very toxic to aquatic life.
  • Very toxic to aquatic life with long lasting effects.
  • Obtain special instructions before use.
  • Avoid breathing dust/fume/gas/mist/vapours/spray.
  • Do not eat, drink or smoke when using this product.
  • Contaminated work clothing should not be allowed out of the workplace.
  • Avoid release to the environment.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF SWALLOWED:
  • IF exposed or concerned:
  • Call a POISON CENTER/doctor/ if you feel unwell.
  • Get medical advice/attention.
  • Rinse mouth.
  • If skin irritation or rash occurs:
  • Collect spillage.
  • Dispose of contents/container to

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

Need this as an actual label? Open Cobalt Sulfate in the GHS label constructor →

07 · Health hazards

Cobalt Sulfate health hazards and exposure limits

Cobalt Sulfate hazard summary

May cause skin sensitization and asthma after prolonged contact; [ICSC] An irritant; May cause skin and respiratory sensitization after prolonged contact; [MSDSonline] See Cobalt.

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

Cobalt Sulfate carcinogenicity classification

This listing of the class of cobalt and cobalt compounds that release cobalt ions in vivo supersedes the previous listing of cobalt sulfate in the Report on Carcinogens. The compound cobalt sulfate was first listed in the Eleventh Report on Carcinogens in 2004 as reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity in experimental animals.

Source: Hazardous Substances Data Bank (HSDB)

Cobaltous Sulfate: reasonably anticipated to be a human carcinogen.

Source: Hazardous Substances Data Bank (HSDB)

An IARC group and a CLP classification answer different questions. IARC judges whether the evidence for cancer in humans is strong enough; CLP Annex VI is the legally binding EU classification. A substance can carry one and not the other.

08 · 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.

Cobalt Sulfate melting point

Property Value Conditions Source
Melting point 735 °C (1355 °F) HSDB

Cobalt Sulfate density

Property Value Conditions Source
Density 3.71 g/cm³ ICSC
1.948 g/cm³ at 20 °C CAMEO
3.71 g/cm³ at 25 °C HSDB

Cobalt Sulfate solubility

Property Value Conditions Source
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.

09 · Handling and storage

Cobalt Sulfate storage and handling

Cobalt Sulfate safe storage

Separated from strong oxidants. Store in an area without drain or sewer access. Provision to contain effluent from fire extinguishing.

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

Cobalt Sulfate storage conditions

Separated from strong oxidants.

Source: Hazardous Substances Data Bank (HSDB)

Cobalt Sulfate incompatible materials

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

Source: Hazardous Substances Data Bank (HSDB)

Cobalt Sulfate 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 →

10 · Questions

Cobalt Sulfate — frequently asked questions

What is the CAS number of Cobalt Sulfate?

The CAS number of Cobalt Sulfate is 10124-43-3. Its EC number is 233-334-2.

What is the chemical formula of Cobalt Sulfate?

The molecular formula of Cobalt Sulfate is CoO4S and its molecular weight is 155 g/mol.

What does a Cobalt Sulfate label have to show?

Under CLP Annex VI the label for Cobalt Sulfate carries the pictograms Health hazard, Exclamation mark and Environment and the signal word is Danger.

Is Cobalt Sulfate flammable?

CLP Annex VI assigns Cobalt Sulfate 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 Cobalt Sulfate a carcinogen?

Yes. CLP Annex VI classifies Cobalt Sulfate as a category 1A or 1B carcinogen and assigns it H350i: may cause cancer by inhalation.

What is the melting point of Cobalt Sulfate?

The melting point reported for Cobalt Sulfate is 735 °C (1355 °F) (HSDB).

How should Cobalt Sulfate be stored?

Separated from strong oxidants. (Hazardous Substances Data Bank (HSDB))

Nearby

Substances next to Cobalt Sulfate

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