Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

Build a label

Substance profile

Cobalt chloride (cocl2)

Cobalt chloride (cocl2) is pale-blue hygroscopic leaflets; colorless in very thin layers with a slight sharp odor.

CAS 7646-79-9 Cl2Co 129.84 g/mol Danger

01 · Identification

What Cobalt chloride (cocl2) is

Cobalt chloride (cocl2) is pale-blue hygroscopic leaflets; colorless in very thin layers with a slight sharp odor. Its molecular formula is Cl2Co and its molecular weight is 129.84 g/mol. It boils at 1049 °C, melts at 735 °C, is soluble in water.

Under the GHS it carries the signal word Danger.

02 · Identifiers

Cobalt chloride (cocl2) identifiers and molecular data

Cobalt chloride (cocl2) CAS number and EC number

CAS number7646-79-9
EC number231-589-4
Index number (CLP Annex VI)027-004-00-5

Cobalt chloride (cocl2) molecular formula and molecular weight

Molecular formulaCl2Co
Molecular weight129.84 g/mol

Other names for Cobalt chloride (cocl2)

  • cobalt dichloride

03 · GHS classification

Cobalt chloride (cocl2) hazard classification

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

Cobalt chloride (cocl2) pictograms and signal word

Signal wordDanger

Cobalt chloride (cocl2) hazard class and category

GHS hazard classes Cobalt chloride (cocl2) 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 chloride (cocl2) hazard statements (H-codes)

Hazard statements assigned to Cobalt chloride (cocl2)
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 chloride (cocl2). 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 chloride (cocl2)

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 chloride… 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 chloride (cocl2) precautionary statements

CLP Annex VI assigns 14 precautionary statements to Cobalt chloride (cocl2). 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 chloride (cocl2) 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 дихлорид
Spanish español Dicloruro de cobalto
Czech čeština chlorid kobaltnatý
Danish dansk cobaltdichlorid
German Deutsch Cobaltdichlorid
Estonian eesti koobaltdikloriid
Greek ελληνικά διχλωριούχο κοβάλτιο
English English cobalt dichloride
French français dichlorure de cobalt
Croatian hrvatski kobaltov diklorid
Italian italiano dicloruro di cobalto
Latvian latviešu kobalta dihlorīds
Lithuanian lietuvių kobalto dichloridas
Hungarian magyar kobalt-diklorid
Maltese Malti diklorur tal-kobalt
Dutch Nederlands kobaltdichloride
Polish polski dichlorek kobaltu
Portuguese português dicloreto de cobalto
Romanian română diclorură de cobalt
Slovak slovenčina chlorid kobaltnatý
Slovenian slovenščina kobaltov diklorid
Finnish suomi kobolttidikloridi
Swedish svenska koboltdiklorid

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 chloride (cocl2) GHS label elements

Everything CLP Annex VI fixes for Cobalt chloride (cocl2), 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 chloride (cocl2)

  • 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 chloride (cocl2) in the GHS label constructor →

07 · Health hazards

Cobalt chloride (cocl2) health hazards and exposure limits

Cobalt chloride (cocl2) hazard summary

An eye irritant; May cause skin sensitization and asthma after prolonged contact; [ICSC] The anhydrous form is very hygroscopic and converts into the hexahydrate form in moist air, changing color from blue to red. [Ullmann] Cobalt chloride is a potent allergen; [Kanerva, p. 506] See Cobalt.

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

Cobalt chloride (cocl2) carcinogenicity classification

... There is limited evidence for the carcinogenicity of cobalt(II) chloride in experimental animals. ... Overall Evaluation: Cobalt and cobalt compounds are possibly carcinogenic to humans (Group 2B). /Cobalt and cobalt compounds/

Source: Hazardous Substances Data Bank (HSDB)

There is inadequate evidence for the carcinogenicity of cobalt and cobalt compounds in humans. There is sufficient evidence for the carcinogenicity of cobalt metal powder in experimental animals. There is limited evidence for the carcinogenicity of metal alloys containing cobalt, chromium and molybdenum in experimental animals. ... Overall Evaluation: Cobalt and cobalt compounds are possibly carcinogenic to humans (Group 2B). /Cobalt and cobalt compounds/

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 chloride (cocl2) 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 chloride (cocl2) boiling point

Property Value Conditions Source
Boiling point 1049 °C (1920.2 °F) HSDB
1049 °C (1920.2 °F) at 760 mmHg DOE PAC

Cobalt chloride (cocl2) melting point

Property Value Conditions Source
Melting point 735 °C (1355 °F) HSDB
86.11 °C (187 °F) CAMEO
737 °C (1358.6 °F) DOE PAC

Cobalt chloride (cocl2) density

Property Value Conditions Source
Density 1.924 g/cm³ at 20 °C CAMEO
3.36 g/cm³ at 25 °C HSDB
2.477 g/cm³ at 25 °C HSDB

Cobalt chloride (cocl2) solubility

Property Value Conditions Source
Solubility Soluble in water HSDB
Soluble in alcohols, acetone, ether, glycerol, and pyridine HSDB
53.420 lb/100 lb water at 70 °F at 21.11 °C HSDB

Cobalt chloride (cocl2) vapor pressure

Property Value Conditions Source
Vapor pressure 75.0062 mmHg at 818 °C HSDB
75 mmHg at 818 °C DOE PAC

Cobalt chloride (cocl2) lower explosive limit (LEL)

Property Value Conditions Source
Lower explosive limit (LEL) Reacts violently with alkali metals such as potassium or sodium causing fire and explosion hazard. HSDB

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

09 · Handling and storage

Cobalt chloride (cocl2) storage and handling

Cobalt chloride (cocl2) storage conditions

Keep container tightly closed in a dry and well-ventilated place. ... Moisture sensitive. Handle and store under inert gas. Hygroscopic. ... Storage class (TRGS 510): Non-combustible, acute toxic Cat.3 / toxic hazardous materials or hazardous materials causing chronic effects.

Source: Hazardous Substances Data Bank (HSDB)

Cobalt chloride (cocl2) incompatible materials

Incompatible materials: Oxidizing agents, alkali metals.

Source: Hazardous Substances Data Bank (HSDB)

Cobalt chloride (cocl2) reactivity

A 0.2 molar aqueous solution has a pH of 4.6. COBALT CHLORIDE acts as a weakly acidic inorganic salt, which is 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. Potassium or sodium metals act to reduce metal halides, producing exothermic reactions, even explosions [Bretherick, 5th Ed., 1995].

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Cobalt chloride (cocl2) in the storage compatibility matrix →

10 · Questions

Cobalt chloride (cocl2) — frequently asked questions

What is the CAS number of Cobalt chloride (cocl2)?

The CAS number of Cobalt chloride (cocl2) is 7646-79-9. Its EC number is 231-589-4.

What is the chemical formula of Cobalt chloride (cocl2)?

The molecular formula of Cobalt chloride (cocl2) is Cl2Co and its molecular weight is 129.84 g/mol.

What does a Cobalt chloride (cocl2) label have to show?

Under CLP Annex VI the label for Cobalt chloride (cocl2) carries the pictograms Health hazard, Exclamation mark and Environment and the signal word is Danger.

Is Cobalt chloride (cocl2) flammable?

CLP Annex VI assigns Cobalt chloride (cocl2) 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 chloride (cocl2) a carcinogen?

Yes. CLP Annex VI classifies Cobalt chloride (cocl2) as a category 1A or 1B carcinogen and assigns it H350i: may cause cancer by inhalation.

What is the boiling point of Cobalt chloride (cocl2)?

The boiling point reported for Cobalt chloride (cocl2) is 1049 °C (1920.2 °F) (HSDB).

What is the melting point of Cobalt chloride (cocl2)?

The melting point reported for Cobalt chloride (cocl2) is 735 °C (1355 °F) (HSDB).

How should Cobalt chloride (cocl2) be stored?

Keep container tightly closed in a dry and well-ventilated place. ... Moisture sensitive. Handle and store under inert gas. Hygroscopic. ... Storage class (TRGS 510): Non-combustible, acute toxic Cat.3 / toxic hazardous materials or hazardous materials causing chronic effects. (Hazardous Substances Data Bank (HSDB))

Nearby

Substances next to Cobalt chloride (cocl2)

Keep going: substances starting with C, or search the whole database by name, CAS number, pictogram or signal word.

Get the free GHS / CLP / OSHA deadline calendar

Verified 2026–2029 compliance dates in one PDF — plus alerts when the rules change.