View source for Cobalt(II) chloride

{{Redirect|CoCl2|the compound with molecular formula {{chem2|COCl2}}|Phosgene}}
{{chembox
| Verifiedfields = changed
| Watchedfields  = changed
| verifiedrevid  = 476995997
| Name           = Cobalt(II) chloride
| ImageFile    = Cobaltous chloride.jpg
| ImageCaption = Hexahydrate
| ImageFile1    = Cobaltous chloride anhydrous.jpg
| ImageCaption1 = Anhydrous
| IUPACName      = Cobalt(II) chloride
| OtherNames     = Cobaltous chloride<br />Cobalt dichloride<br>Muriate of cobalt<ref>{{cite web|url=http://www.chemindustry.com/chemicals/0519906.html.|title=Cobalt muriate, CAS Number: 7646-79-9|website=www.chemindustry.com|access-date=19 April 2018|archive-date=28 May 2019|archive-url=https://web.archive.org/web/20190528032158/http://www.chemindustry.com/chemicals/0519906.html.|url-status=dead}}</ref>
| Section1       = {{Chembox Identifiers
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 22708
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = EVS87XF13W
| UNII1_Ref = {{fdacite|correct|FDA}}
| UNII1 = 17AVG63ZBC
| UNII1_Comment = (hexahydrate)
| InChI = 1/2ClH.Co/h2*1H;/q;;+2/p-2
| ChEBI_Ref = {{ebicite|correct|EBI}}
| ChEBI = 35696
| SMILES = Cl[Co]Cl
| SMILES_Comment = anhydrous
| SMILES1 = Cl[Co-4](Cl)([OH2+])([OH2+])([OH2+])[OH2+].O.O
| SMILES1_Comment = hexahydrate
| InChIKey = GVPFVAHMJGGAJG-NUQVWONBAU
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/2ClH.Co/h2*1H;/q;;+2/p-2
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = GVPFVAHMJGGAJG-UHFFFAOYSA-L
| CASNo = 7646-79-9
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo2_Ref = {{cascite|changed|CAS}}
| CASNo2 = 16544-92-6
| CASNo2_Comment = (dihydrate)
| CASNo3_Ref = {{cascite|correct|CAS}}
| CASNo3 = 7791-13-1
| CASNo3_Comment = (hexahydrate)
| PubChem = 3032536
| RTECS = GF9800000
| UNNumber = 3288
| EINECS = 231-589-4
 }}
| Section2       = {{Chembox Properties
| Formula = CoCl<sub>2</sub>
| MolarMass = 129.839 g/mol (anhydrous) <br> 165.87 g/mol (dihydrate) <br />237.93 g/mol (hexahydrate)
| Appearance = blue crystals (anhydrous) <br> violet-blue (dihydrate) <br>  rose red crystals (hexahydrate)
| Density = 3.356 g/cm<sup>3</sup> (anhydrous) <br> 2.477 g/cm<sup>3</sup> (dihydrate) <br> 1.924 g/cm<sup>3</sup> (hexahydrate)
| Solubility = 43.6 g/100 mL (0 °C) <br> 45 g/100 mL (7 °C)<br />52.9 g/100 mL (20 °C) <br> 105 g/100 mL (96 °C) 
| SolubleOther = 38.5 g/100 mL (methanol) <br> 8.6 g/100 mL (acetone) <br> soluble in [[ethanol]], [[pyridine]], [[glycerol]]
| MeltingPtC = 726
| MeltingPt_notes = ±2 (anhydrous)<ref name=wojak/> <br> 140 °C (monohydrate) <br> 100 °C (dihydrate) <br> 86 °C (hexahydrate)
| BoilingPtC = 1049
| MagSus = +12,660·10<sup>−6</sup> cm<sup>3</sup>/mol
 }}
| Section3       = {{Chembox Structure
| Coordination = hexagonal (anhydrous) <br> monoclinic (dihydrate) <br> [[Octahedron|Octahedral]] (hexahydrate)
| CrystalStruct = [[Cadmium chloride#Structure|CdCl<sub>2</sub> structure]]
 }}
| Section7       = {{Chembox Hazards
| ExternalSDS = [http://www.inchem.org/documents/icsc/icsc/eics0783.htm ICSC 0783]
| GHSPictograms = {{GHS06}} {{GHS08}} {{GHS09}}
| GHSSignalWord =
| NFPA-H = 3
| NFPA-F = 0
| NFPA-R = 0
| NFPA-S =
| NFPA_ref = <ref>[http://datasheets.scbt.com/sc-252623.pdf Santa Cruz Biotechnology: Cobalt(II) chloride]</ref>
| FlashPt = Non-flammable
| LD50 = 80 mg/kg (rat, oral)
 }}
| Section8       = {{Chembox Related
| OtherAnions = [[Cobalt(II) fluoride]]<br />[[Cobalt(II) bromide]]<br />[[Cobalt(II) iodide]]
| OtherCations = [[Rhodium(III) chloride]]<br />[[Iridium(III) chloride]]
}}
}}

'''Cobalt(II) chloride''' is an [[inorganic compound]], a salt of [[cobalt]] and [[chlorine]], with the formula {{chem|CoCl|2}}. The compound forms several [[hydrate]]s {{chem|CoCl|2}}·''n''{{chem|H|2|O}}, for ''n'' = 1, 2, 6, and 9. Claims of the formation of tri- and tetrahydrates have not been confirmed.<ref name=saugier>M. T. Saugier, M. Noailly, R. Cohen-Adad, F. Paulik, and J. Paulik (1977): "Equilibres solide ⇄ liquide ⇆ vapeur du systeme binaire {{chem|CoCl|2}}-{{chem|H|2|O}}" ''Journal of Thermal Analysis'', volume 11, issue 1, pages 87–100. {{doi|10.1007/BF02104087}} Note: the lowest point of fig.6 is inconsistent with fig.7; probably should be at -27.8 C instead of 0 C.</ref> The anhydrous form is a blue crystalline solid; the dihydrate is purple and the hexahydrate is pink. Commercial samples are usually the hexahydrate, which is one of the most commonly used cobalt salts in the lab.<ref name=g&e>{{Greenwood&Earnshaw2nd}}</ref>

==Properties==
===Anhydrous===
At room temperature, anhydrous cobalt chloride has the [[cadmium chloride]] structure ({{chem|CdCl|2}}) (R{{overline|3}}m) in which the cobalt(II) ions are octahedrally coordinated. At about 706&nbsp;°C (20 degrees below the melting point), the [[Coordination complex|coordination]] is believed to change to tetrahedral.<ref name=wojak/> The vapor pressure has been reported as 7.6&nbsp;[[millimeter of mercury|mmHg]] at the melting point.<ref name=saeki>Yuzo Saeki, Ryoko Matsuzaki, Naomi Aoyama (1977): "The vapor pressure of cobalt dichloride". ''Journal of the Less Common Metals'', volume 55, issue 2, pages 289-291. {{doi|10.1016/0022-5088(77)90204-1}}</ref>

===Solutions===
Cobalt chloride is fairly [[Solubility|soluble]] in water.  Under atmospheric pressure, the [[mass concentration (chemistry)|mass concentration]] of a [[saturated solution]] of {{chem|CoCl|2}} in water is about 54% at the boiling point, 120.2&nbsp;°C; 48% at 51.25&nbsp;°C; 35% at 25&nbsp;°C; 33% at 0&nbsp;°C; and 29% at −27.8&nbsp;°C.<ref name=saugier/>

Diluted [[aqueous]] solutions of {{chem|CoCl|2}} contain the species {{chem|[|Co|(|H|2|O|)|6|]|2+}}, besides [[chloride]] ions.  Concentrated solutions are red at room temperature but become blue at higher temperatures.<ref>''The Merck Index'', 7th edition, Merck & Co, Rahway, New Jersey, USA, 1960.</ref>

===Hydrates===
The crystal unit of the solid hexahydrate {{chem|CoCl|2}}•6{{chem|H|2|O}} contains the neutral molecule ''trans''-{{chem|CoCl|2|(|H|2|O|)|4}} and two molecules of [[water of crystallization]].<ref>{{Wells5th}}</ref> This species dissolves readily in water and [[ethanol|alcohol]].

The anhydrous salt is [[hygroscopic]] and the hexahydrate is [[deliquescent]].{{citation needed|date=February 2019}} The dihydrate, CoCl<sub>2</sub>(H<sub>2</sub>O)<sub>2</sub>, is a [[coordination polymer]].  Each Co center is coordinated to four doubly [[bridging chloride ligand]]s.  The octahedron is completed by a pair of mutually trans [[aquo ligand]]s.<ref>{{cite journal |title=Crystal structures of manganese(II) and iron(II) chloride dihydrate |author1=Morosin, B. |author2=Graeber, E. J. |journal=Journal of Chemical Physics |year=1965 |volume=42 |issue=3 |pages=898–901 |doi=10.1063/1.1696078 |bibcode=1965JChPh..42..898M}}</ref>
{{multiple image
 | align = center
 | width = 200
 | footer = Structures of the forms of cobalt(II) chloride 
 | image1 = Cobalt(II)-chloride-3D-balls.png
 | alt1 = 
 | caption1 = Anhydrous
 | image2 = MX2(H2O)2.png
 | alt2 = 
 | caption2 = Dihydrate
 | image3 = MCl2(aq)6forFeCoNi.png
 | alt3 = 
 | caption3 = Hexahydrate}}

==Preparation==
Cobalt chloride can be prepared in aqueous solution from [[cobalt(II) hydroxide]] or [[cobalt(II) carbonate]] and [[hydrochloric acid]]:
:{{chem|CoCO|3}} + 2 HCl<sub>(aq)</sub> → {{chem|CoCl|2}}<sub>(aq)</sub>  +  {{chem|CO|2}}  +  {{chem|H|2|O}}

:{{chem|Co|(|OH|)|2}} + 2 HCl<sub>(aq)</sub>  → {{chem|CoCl|2}}<sub>(aq)</sub>  +  2{{chem|H|2|O}}

The solid dihydrate and hexahydrate can be obtained by evaporation.  Cooling saturated aqueous solutions yields the dihydrate between 120.2&nbsp;°C and 51.25&nbsp;°C, and the hexahydrate below 51.25&nbsp;°C. Water ice, rather than cobalt chloride, will crystallize from solutions with concentration below 29%. The monohydrate and the anhydrous forms can be obtained by cooling solutions only under high pressure, above 206&nbsp;°C and 335&nbsp;°C, respectively.<ref name=saugier/>

The anhydrous compound can be prepared by heating the hydrates.<ref>John Dallas Donaldson, Detmar Beyersmann, "Cobalt and Cobalt Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. {{doi|10.1002/14356007.a07_281.pub2}}</ref>

On rapid heating or in a closed container, each of the 6-, 2-, and 1- hydrates partially melts into a mixture of the next lower hydrate and a saturated solution—at 51.25&nbsp;°C, 206&nbsp;°C, and 335&nbsp;°C, respectively.<ref name=saugier/> On slow heating in an open container, so that the water vapor pressure over the solid is practically zero, water evaporates out of each of the solid 6-, 2-, and 1- hydrates, leaving the next lower hydrate, at about 40°C, 89°C, and 125°C, respectively.  If the partial pressure of the water vapor is in equilibrium with the solid, as in a confined but not pressurized container, the decomposition occurs at about 115°C, 145°C, and 195°C, respectively.<ref name=saugier/>

Dehydration can also be effected with [[trimethylsilyl chloride]]:<ref>{{cite book |chapter=Solvated and Unsolvated Anhydrous Metal Chlorides from Metal Chloride Hydrates |title=Inorganic Syntheses |volume=29 |author1=Philip Boudjouk |author2=Jeung-Ho So|pages=108–111 |doi=10.1002/9780470132609.ch26 |date=2007 |isbn=9780470132609}}</ref>
:{{chem|CoCl|2}}•6{{chem|H|2|O}} + 12 {{chem|(|CH|3|)|3|SiCl}} → {{chem|CoCl|2}} + 6{{chem|[|(|CH|3|)|3|SiCl|]|2|O}} + 12 HCl

The anhydrous compound can be purified by sublimation in vacuum.<ref name=wojak>{{cite journal |author1=Wojakowska, A. |author2=Krzyżak, E. |author3=Plińska, S. |date=2007 |title=Melting and high-temperature solid state transitions in cobalt(II) halides |journal=Journal of Thermal Analysis and Calorimetry |volume=88 |issue=2 |pages=525–530 |doi=10.1007/s10973-006-8000-9}}</ref>

==Reactions==
In the laboratory, cobalt(II) chloride serves as a common precursor to other cobalt compounds. Generally, diluted aqueous solutions of the salt behave like other cobalt(II) salts since these solutions consist of the {{chem|[|Co|(|H|2|O|)|6|]|2+}} ion regardless of the anion. For example, such solutions give a precipitate of [[cobalt sulfide]] {{chem|CoS}} upon treatment with [[hydrogen sulfide]] {{chem|H|2|S}}.{{cn|date=September 2023}}

===Complexed chlorides===
The hexahydrate and the anhydrous salt are weak [[Lewis acid]]s.  The [[adduct]]s are usually either [[octahedral]] or [[tetrahedral]]. It forms an [[metal-pyridine complex|octahedral complex with pyridine]] ({{chem|C|5|H|5|N}}):<ref name=Long>{{cite journal |doi=10.1021/ic50184a002|title=Crystal and Molecular Structures of ''trans''-Tetrakis(pyridine)dichloroiron(II), -Nickel(II), and -Cobalt(II) and ''trans''-Tetrakis(pyridine)dichloroiron(II) Monohydrate|year=1978|last1=Long|first1=Gary J.|last2=Clarke|first2=Peter J.|journal=Inorganic Chemistry|volume=17|issue=6|pages=1394–1401}}</ref>
:{{chem|CoCl|2}}·6{{chem|H|2|O}} + 4 {{chem|C|5|H|5|N}}  →  {{chem|CoCl|2|(|C|5|H|5|N|)|4}} + 6 {{chem|H|2|O}}
With [[triphenylphosphine]] ({{chem|P(C|6|H|5|)|3}}), a tetrahedral complex results:
:{{chem|CoCl|2}}·6{{chem|H|2|O}} + 2 {{chem|P(C|6|H|5|)|3}} → {{chem|CoCl|2|[P(C|6|H|5|)|3|]|2}} + 6 {{chem|H|2|O}}

Salts of the anionic complex CoCl<sub>4</sub><sup>2−</sup> can be prepared using tetraethylammonium chloride:<ref>{{cite book|author = Gill, N. S.|author2 = Taylor, F. B.| title=[[Inorg. Synth.|Inorganic Syntheses]] | chapter=Tetrahalo Complexes of Dipositive Metals in the First Transition Series |name-list-style = amp|year = 1967|volume = 9|pages = 136–142|doi = 10.1002/9780470132401.ch37|isbn = 9780470132401}}</ref>
:{{chem|CoCl|2}} + 2 [(C<sub>2</sub>H<sub>5</sub>)<sub>4</sub>N]Cl → [(C<sub>2</sub>H<sub>5</sub>)<sub>4</sub>N)]<sub>2</sub>[CoCl<sub>4</sub>]
The tetrachlorocobaltate ion [CoCl<sub>4</sub>]<sup>2−</sup> is the blue ion that forms upon addition of [[hydrochloric acid]] to aqueous solutions of hydrated cobalt chloride, which are pink.

===Reduction===
[[File:Co(norbornyl)4.png|thumb|left|The structure of a cobalt(IV) [[coordination complex]] with the [[norbornyl]] anion]]
Reaction of the anhydrous compound with [[sodium cyclopentadienide]] gives [[cobaltocene]] {{chem|Co|(|C|5|H|5|)|2}}. This 19-electron species is a good reducing agent, being readily oxidised to the yellow [[18-Electron rule|18-electron]] cobaltocenium cation {{chem|[|Co|(|C|5|H|5|)|2|]|+}}.

===Oxidation to cobalt(III)===
Compounds of cobalt in the +3 oxidation state exist, such as [[cobalt(III) fluoride]] {{chem|CoF|3}}, [[cobalt(III) nitrate|nitrate]] {{chem|Co|(|NO|3|)|3}}, and [[cobalt(III) sulfate|sulfate]] {{chem|Co|2|(|SO|4|)||3}}; however, [[cobalt(III) chloride]] {{chem|CoCl|3}} is not stable in normal conditions, and would decompose immediately into {{chem|CoCl|2}} and [[chlorine]].<ref>''Handbook of Chemistry and Physics'', 71st edition, CRC Press, Ann Arbor, Michigan, 1990.</ref>

On the other hand, cobalt(III) chlorides can be obtained if the cobalt is bound also to other ligands of greater Lewis basicity than chloride, such as [[amine]]s.  For example, in the presence of [[ammonia]], cobalt(II) chloride is readily [[redox|oxidised]] by atmospheric [[oxygen]] to [[hexamminecobalt(III) chloride]]:
:4 {{chem|CoCl|2}}·6{{chem|H|2|O}} + 4 {{chem|NH|4}}Cl + 20 {{chem|NH|3}} + {{chem|O|2}} → 4 {{chem|[|Co|(|NH|3|)|6|]|Cl|3}} + 26 {{chem|H|2|O}}
Similar reactions occur with other [[amine]]s.  These reactions are often performed in the presence of [[carbon|charcoal]] as a catalyst, or with [[hydrogen peroxide]] {{chem|H|2|O|2}} substituted for atmospheric oxygen. Other highly basic ligands, including [[carbonate]], [[acetylacetone|acetylacetonate]], and [[oxalate]], induce the formation of Co(III) derivatives. Simple carboxylates and halides do not.{{cn|date=September 2023}}

Unlike Co(II) [[Complex (chemistry)|complexes]], Co(III) complexes are very slow to exchange [[ligand]]s, so they are said to be ''kinetically inert''. The German chemist [[Alfred Werner]] was awarded the [[Nobel Prize]] in 1913 for his studies on a series of these cobalt(III) compounds, work that led to an understanding of the structures of such [[Complex (chemistry)|coordination compounds]].{{cn|date=September 2023}}

===Oxidation to cobalt(IV)===
Reaction of 1-norbornyllithium with the {{chem|CoCl|2}}·THF in pentane produces the brown, thermally stable [[tetrakis(1-norbornyl)cobalt(IV)]]<ref>{{cite journal|author = Barton K. Bower|author2 = Howard G. Tennent|name-list-style = amp|title = Transition metal bicyclo[2.2.1]hept-1-yls|journal = [[J. Am. Chem. Soc.]]|year = 1972|volume = 94|issue = 7|pages = 2512–2514|doi = 10.1021/ja00762a056}}</ref><ref>{{cite journal|journal = [[J. Chem. Soc., Chem. Commun.]]|year = 1986|issue = 19|pages = 1491–1492|doi = 10.1039/C39860001491|title = Tetrakis(1-norbornyl)cobalt, a low spin tetrahedral complex of a first row transition metal|author = Erin K. Byrne|author2 = Darrin S. Richeson|author3 = Klaus H. Theopold|name-list-style = amp}}</ref> — a rare example of a stable transition metal/saturated alkane compound,<ref name="g&e" /> different products are obtained in other solvents.<ref>{{cite journal |title = Synthesis, characterization, and electron-transfer reactivity of norbornyl complexes of cobalt in unusually high oxidation states|author = Erin K. Byrne|author2 = Klaus H. Theopold|journal = [[J. Am. Chem. Soc.]]|year = 1989|volume = 111|issue = 11|pages = 3887–3896|doi = 10.1021/ja00193a021}}</ref>

== Moisture indication ==
[[File:Blue silica gel.jpg|left|thumb|The deep blue colour of this moisture indicating [[silica gel]] is due to cobalt chloride. When hydrated the colour changes to a light pink/purple.]]
Cobalt chloride is a common visual moisture indicator due to its distinct colour change when hydrated. The colour change is from some shade of blue when dry, to a pink when hydrated, although the shade of colour depends on the substrate and concentration. It is impregnated into paper to make test strips for detecting moisture in solutions, or more slowly, in air/gas. [[Desiccant]]s such as [[silica gel]] can incorporate cobalt chloride to indicate when it is "spent" (i.e. hydrated).<ref>{{Cite journal|last=Solomon|first=M. E.|date=February 1945|title=The use of cobalt salts as indicators of humidity and moisture|url=https://onlinelibrary.wiley.com/doi/10.1111/j.1744-7348.1945.tb06763.x|journal=Annals of Applied Biology|language=en|volume=32|issue=1|pages=75–85|doi=10.1111/j.1744-7348.1945.tb06763.x|issn=0003-4746|url-access=subscription}}</ref>

==Health issues==
Cobalt is essential for most higher forms of life, but more than a few milligrams each day is harmful.  Although poisonings have rarely resulted from cobalt compounds, their chronic ingestion has caused serious health problems at doses far less than the lethal dose. In 1966, the addition of cobalt compounds to stabilize [[beer foam]] in Canada led to a peculiar form of toxin-induced [[cardiomyopathy]], which came to be known as ''beer drinker's cardiomyopathy''.<ref>{{cite journal |author= Morin Y |author2= Tětu A |author3= Mercier G|title=Quebec beer-drinkers' cardiomyopathy: Clinical and hemodynamic aspects |journal=Annals of the New York Academy of Sciences |volume=156 |issue= 1 |pages=566–576 |date=1969|pmid=5291148 |doi=10.1111/j.1749-6632.1969.tb16751.x|bibcode = 1969NYASA.156..566M |s2cid= 7422045 }}</ref><ref>{{cite journal|title = Cobalt|author = Barceloux, Donald G.|author2 = Barceloux, Donald|name-list-style = amp |doi = 10.1081/CLT-100102420|pmid = 10382556|journal = Clinical Toxicology|volume = 37|issue = 2|date = 1999| pages = 201–216}}</ref><ref>[https://pubchem.ncbi.nlm.nih.gov/compound/Cobalt_sulfate#section=Human-Toxicity-Excerpts   11.1.5 The unusual type of myocardiopathy recognized in 1965 and 1966 in Quebec (Canada), Minneapolis (Minnesota), Leuven (Belgium), and Omaha (Nebraska) was associated with episodes of acute heart failure (e/g/, 50 deaths among 112 beer drinkers).]</ref>

Furthermore, cobalt(II) chloride is suspected of causing [[cancer]] (i.e., possibly [[carcinogen]]ic, [[IARC Group 2B]]) as per the [[International Agency for Research on Cancer]] (IARC) Monographs.<ref>[http://publications.iarc.fr/_publications/media/download/2705/29aacee6b89ff816188dcd990b61a16ad6486eec.pdf [PDF]</ref>

In 2005–06, cobalt chloride was the eighth-most-prevalent [[allergen]] in [[patch test]]s (8.4%).<ref>Zug KA, Warshaw EM, Fowler JF Jr, Maibach HI, Belsito DL, Pratt MD, Sasseville D, Storrs FJ, Taylor JS, Mathias CG, Deleo VA, Rietschel RL, Marks J. Patch-test results of the North American Contact Dermatitis Group 2005–2006. Dermatitis. 2009 May–Jun;20(3):149-60.</ref>

==Other uses==
* [[Invisible ink]]: when suspended in solution, cobalt(II) chloride can be made to appear invisible on a surface; when that same surface is subsequently exposed to significant heat (such as from a handheld [[heat gun]] or lighter) the ink reversibly changes to blue.<ref>{{cite web|url=https://edu.rsc.org/in-search-of-solutions/making-invisible-ink/1178.article|title=Making invisible ink|accessdate=7 April 2023 |publisher=[[Royal Society of Chemistry]]}}</ref>
* Cobalt chloride is an established chemical inducer of hypoxia-like responses such as [[erythropoiesis]].{{citation needed|date=November 2019}} Cobalt supplementation is not banned and therefore would not be detected by current anti-doping testing.<ref>{{cite journal |pmid=16244201 |doi=10.1136/bjsm.2005.019232 |volume=39 |issue=11 |title=Cobalt chloride administration in athletes: a new perspective in blood doping? |pmc=1725077 |date=November 2005 |journal=Br J Sports Med |pages=872–873 |vauthors=Lippi G, Franchini M, Guidi GC}}</ref> Cobalt chloride is a banned substance under the Australian Thoroughbred Racing Board.<ref>{{cite news |title=Cobalt crisis turns the eyes of the world onto Australian racing |url=https://www.smh.com.au/sport/racing/cobalt-crisis-turns-the-eyes-of-the-world-onto-australian-racing-20150206-137w22.html |first=Patrick|last=Bartley|newspaper=The Sydney Morning Herald |date=6 February 2015}}</ref>
* Cobalt chloride is one method used to induce pulmonary arterial hypertension in animals for research and evaluation of treatment efficacy.

==References==
{{Reflist|2}}

==External links==
{{Commons category|Cobalt(II) chloride|lcfirst=yes}}
* [http://www.inchem.org/documents/icsc/icsc/eics0783.htm International Chemical Safety Card 0783]
* [https://web.archive.org/web/20060219230038/http://www.npi.gov.au/database/substance-info/profiles/26.html National Pollutant Inventory – Cobalt fact sheet]
* [https://web.archive.org/web/20051012230942/http://www-cie.iarc.fr/htdocs/monographs/vol52/11-cobaltandcobaltcomp.htm IARC Monograph "Cobalt and Cobalt Compounds"]

{{Cobalt compounds}}
{{Chlorides}}

[[Category:Cobalt(II) compounds]]
[[Category:Inorganic compounds]]
[[Category:Chlorides]]
[[Category:Metal halides]]
[[Category:IARC Group 2B carcinogens]]
[[Category:Deliquescent materials]]