{"id":10605,"date":"2026-03-08T07:16:59","date_gmt":"2026-03-08T07:16:59","guid":{"rendered":"https:\/\/longchangextracts.com\/cobalt-chloride-cas-7646-79-9-properties-uses-and-applications\/"},"modified":"2026-08-04T09:33:54","modified_gmt":"2026-08-04T09:33:54","slug":"cobalt-chloride-cas-7646-79-9-properties-uses-and-applications","status":"publish","type":"post","link":"https:\/\/longchangextracts.com\/de\/cobalt-chloride-cas-7646-79-9-properties-uses-and-applications\/","title":{"rendered":"What Is Cobalt Chloride? CoCl2 Formula, Uses and Safety"},"content":{"rendered":"
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What Is Cobalt Chloride? CoCl2<\/sub> Formula, Uses and Safety<\/h1>\n

Cobalt chloride<\/strong> usually refers to cobalt(II) chloride, an inorganic cobalt salt with the formula CoCl2<\/sub>. NIST identifies the anhydrous compound as CAS 7646-79-9 with molecular weight 129.839 g\/mol. The frequently searched hexahydrate is a different material form\u2014CoCl2<\/sub>\u00b76H2<\/sub>O, CAS 7791-13-1 and 237.931 g\/mol. A buyer should therefore specify the required hydrate state, CAS, formula, tests and intended process rather than using \u201ccobalt chloride\u201d alone.<\/p>\n

Cobalt chloride identity at a glance<\/h2>\n
\n\n\n\n\n\n\n\n\n\n\n\n
Controlled name<\/th>\nCobalt(II) chloride; cobalt dichloride<\/td>\n<\/tr>\n
CAS Registry Number<\/th>\n7646-79-9 (anhydrous identity)<\/td>\n<\/tr>\n
Molekulare Formel<\/th>\nCoCl2<\/sub> (source display may use Hill order Cl2<\/sub>Co)<\/td>\n<\/tr>\n
Molekulargewicht<\/th>\n129.839 g\/mol (commonly rounded to 129.84)<\/td>\n<\/tr>\n
Oxidation state<\/th>\nCobalt(II), Co2+<\/sup><\/td>\n<\/tr>\n
EC number<\/th>\n231-589-4<\/td>\n<\/tr>\n
PubChem CID<\/th>\n24288<\/td>\n<\/tr>\n
InChIKey<\/th>\nGVPFVAHMJGGAJG-UHFFFAOYSA-L<\/td>\n<\/tr>\n
Distinct common hydrate<\/th>\nCobalt chloride hexahydrate, CAS 7791-13-1, CoCl2<\/sub>\u00b76H2<\/sub>O<\/td>\n<\/tr>\n<\/tbody>\n<\/table><\/div>\n

Identity references: NIST Chemistry WebBook<\/a>, PubChem CID 24288<\/a> and the ECHA cobalt dichloride record<\/a>. These records support public identity fields; they do not establish a current Longchang form, specification, assay, impurity profile, grade, lot result, availability or suitability.<\/p>\n

What does CoCl2<\/sub> mean?<\/h2>\n

CoCl2<\/sub> represents one cobalt atom and two chlorine atoms in the formula unit, with cobalt in the +2 oxidation state. \u201cCobaltous chloride,\u201d \u201ccobalt(II) chloride\u201d and \u201ccobalt dichloride\u201d are names associated with this identity. \u201cCobaltic chloride\u201d or CoCl3<\/sub> describes a different oxidation state and must not be used as a synonym in purchasing documents.<\/p>\n

Is CAS 7646-79-9 the hexahydrate?<\/h2>\n

No. CAS 7646-79-9 identifies the anhydrous cobalt dichloride record. PubChem identifies cobalt chloride hexahydrate as CAS 7791-13-1 with formula CoCl2<\/sub>\u00b76H2<\/sub>O and molecular weight 237.93 g\/mol. Commercial descriptions sometimes mix the anhydrous CAS with a hydrate color or cobalt-content table, so the current supplier specification and lot COA must state the exact form and calculation basis.<\/p>\n

For the full comparison, see Cobalt chloride anhydrous vs hexahydrate: formula, color and hydration<\/a>.<\/p>\n

Why can cobalt chloride change color?<\/h2>\n

Reference descriptions commonly associate less-hydrated cobalt chloride with blue tones and hydrated material with pink or magenta tones. The observed color can also depend on coordination, water activity, solvent, concentration, temperature and matrix. Color alone is therefore not a reliable CAS, hydrate, purity or release test. Use controlled identity methods, water or loss-on-drying controls, assay basis and an applicable lot COA.<\/p>\n

What is cobalt chloride used for?<\/h2>\n

ECHA records industrial contexts involving metal surface treatment, inorganic pigments and frits, glass and ceramic ware, varistors, magnets and professional handling of humidity-indicator articles. These are evidence that the substance appears in reported use contexts\u2014not permission, performance proof or a statement that a current Longchang lot is suitable for every process.<\/p>\n

\n\n\n\n\n\n\n\n\n\n
Reported context<\/th>\nQualification questions before use<\/th>\n<\/tr>\n<\/thead>\n
Surface treatment or plating<\/td>\nRequired cobalt source, hydrate state, solution chemistry, impurity limits, bath\/process controls and regulatory obligations<\/td>\n<\/tr>\n
Pigments, frits, glass or ceramics<\/td>\nMaterial form, thermal process, color target, contaminant limits, worker\/environmental controls and end-market rules<\/td>\n<\/tr>\n
Varistors or magnets<\/td>\nParticle\/form requirements, metal impurities, process compatibility and finished-component qualification<\/td>\n<\/tr>\n
Humidity-indicator articles<\/td>\nExact formulation, article design, exposure scenario, safer-alternative review and market-specific restrictions<\/td>\n<\/tr>\n
Catalyst, battery, reagent or synthesis input<\/td>\nExact reaction\/process evidence, form, methods, acceptance criteria and applicable quality\/regulatory review<\/td>\n<\/tr>\n<\/tbody>\n<\/table><\/div>\n

ECHA use information is available in its cobalt dichloride use-context record<\/a>. A use mention does not establish grade, legal authorization, safe conditions, output performance or product compatibility.<\/p>\n

Safety and regulatory boundary<\/h2>\n

ECHA lists cobalt dichloride on the REACH Candidate List for carcinogenicity and reproductive toxicity and states that Candidate List entries cover anhydrous and hydrated forms. ECHA’s substance information also records harmonized health and environmental hazard classifications. This webpage is not an SDS and does not provide handling or first-aid instructions. Request the current supplier SDS and use it with the buyer’s site, process, exposure scenario, destination rules and risk assessment.<\/p>\n

Review the current ECHA Candidate List<\/a> und substance information<\/a> for the exact regulatory context. A CAS match does not replace buyer legal, EHS or product-stewardship review.<\/p>\n

Claims removed from the earlier pages<\/h2>\n
\n\n\n\n\n\n\n\n\n
Earlier statement<\/th>\nWhy it is not retained<\/th>\nEvidence required before reuse<\/th>\n<\/tr>\n<\/thead>\n
High purity, precise international specifications or multiple grades<\/td>\nNo current controlled specification, methods or applicable lot evidence was shown<\/td>\nApproved current specification, methods, grade definition and lot COA<\/td>\n<\/tr>\n
Reliable supply, consistent availability, competitive price or bulk delivery<\/td>\nNo current inventory, capacity or dated quotation supported the promise<\/td>\nCurrent availability check and destination-specific quotation<\/td>\n<\/tr>\n
Benefits in batteries, catalysts, electroplating, medical research, food packaging or Vitamin B12 production<\/td>\nBroad use lists omit material form, process, performance, exposure and market boundaries<\/td>\nExact use dossier, current material evidence, process validation and jurisdiction review<\/td>\n<\/tr>\n
Generic PPE, storage, first aid and disposal instructions<\/td>\nControls depend on the current product SDS, exposure scenario and local procedure<\/td>\nCurrent supplier SDS and buyer site\/process risk assessment<\/td>\n<\/tr>\n<\/tbody>\n<\/table><\/div>\n

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