Names | |
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IUPAC name Cobalt(III) chloride | |
Other names Cobaltic chloride Cobalt trichloride | |
Identifiers | |
3D model (JSmol) | |
ChemSpider | |
ECHA InfoCard | 100.030.509 |
EC Number |
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PubChem CID | |
CompTox Dashboard (EPA) | |
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Properties | |
CoCl3 | |
Molar mass | 165.2913 g/mol (anhydrous) |
Melting point | Solid decomposes over −60°C |
Solubility | soluble in ethanol, diethyl ether |
Hazards | |
GHS labelling: | |
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Danger | |
H300, H330 | |
P260, P264, P270, P271, P284, P301+P310, P304+P340, P310, P320, P321, P330, P403+P233, P405, P501 | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Cobalt(III) chloride or cobaltic chloride is an unstable and elusive compound of cobalt and chlorine with formula CoCl
3. In this compound, the cobalt atoms have a formal charge of +3. [1]
The compound has been reported to exist in the gas phase at high temperatures, in equilibrium with cobalt(II) chloride and chlorine gas. [2] [3] It has also been found to be stable at very low temperatures, dispersed in a frozen argon matrix. [4]
Some articles from the 1920s and 1930s claim the synthesis of bulk amounts of this compound in pure form; [5] [6] however, those results do not seem to have been reproduced, or have been attributed to other substances like the hexachlorocobaltate(III) anion CoCl3−
6. [1] Those earlier reports claim that it gives green solutions in anhydrous solvents such as ethanol and diethyl ether, and that it is stable only a very low temperatures (below −60 °C). [7]
The infrared spectrum of the compound in frozen argon indicates that the isolated CoCl
3 molecule is planar with D3h symmetry. [4]
A Scientific study of the stability of this and other metal trihalides at 50 °C was published by Nelsoon and Sharpe in 1956. [8]
Aerodynamic properties for the gas phase have been determined by the Glushko Thermocenter of the Russian Academy of Sciences. [9]
Cobalts trichlorides was detected in 1952 by Schäfer and Krehl in the gas phase when cobalt(II) chloride CoCl
2 is heated in an atmosphere of chlorine Cl
2. The trichloride is formed through the equilibrium
At 918 K (below the melting point of CoCl
2, 999 K), the trichloride was the predominant cobalt species in the vapor, with partial pressure of 0.72 mm Hg versus 0.62 for the dichloride. However, equilibrium shifts to the left at higher temperatures. At 1073 K, the partial pressures were 7.3 and 31.3 mm Hg, respectively. [2] [10] [3]
Cobalt trichloride, in amounts sufficient to study spectroscopically, was obtained by Green and others in 1983, by sputtering cobalt electrodes with chlorine atoms and trapping the resulting molecules in frozen argon at 14 K. [4]
A report from 1969 claims that treatment of solid cobalt(III) hydroxide CoOOH·H
2O with anhydrous ether saturated with HCl at −20 °C produces a green solution (stable at −78 °C) with the characteristic spectrum of CoCl
3. [1]
In a 1932 report, the compound was claimed to arise in the electrolysis of cobalt(II) chloride in anhydrous ethanol. [7]
The hexachlorocobaltate(III) anion CoCl3−
6 has been identified in preparations of cobalt(III) salts and hydrochloric acid HCl in glacial acetic acid. [1]
In solutions of cobalt(III) salts with chloride ions, the anionic complexes (H
2O)
5Co(Cl)2+
and (H
2O)
4(OH)Co(Cl)+
are present. [11]
Trichlorides of cobalt(III) complexed with various ligands, such as organic amines, can be quite stable. In particular, hexamminecobalt(III) chloride Co(NH
3)
6Cl
3 is the archetypal Werner complex and has uses in biological research. Another classical example is tris(ethylenediamine)cobalt(III) chloride Co(H
2N–C
2H
4–NH
2)
3Cl
3.
Cerium(III) chloride (CeCl3), also known as cerous chloride or cerium trichloride, is a compound of cerium and chlorine. It is a white hygroscopic salt; it rapidly absorbs water on exposure to moist air to form a hydrate, which appears to be of variable composition, though the heptahydrate CeCl3·7H2O is known. It is highly soluble in water, and (when anhydrous) it is soluble in ethanol and acetone.
Praseodymium(III) chloride is the inorganic compound with the formula PrCl3. Like other lanthanide trichlorides, it exists both in the anhydrous and hydrated forms. It is a blue-green solid that rapidly absorbs water on exposure to moist air to form a light green heptahydrate.
Samarium(III) chloride, also known as samarium trichloride, is an inorganic compound of samarium and chloride. It is a pale yellow salt that rapidly absorbs water to form a hexahydrate, SmCl3.6H2O. The compound has few practical applications but is used in laboratories for research on new compounds of samarium.
Aluminium chloride, also known as aluminium trichloride, is an inorganic compound with the formula AlCl3. It forms hexahydrate with the formula [Al(H2O)6]Cl3, containing six water molecules of hydration. Both are colourless crystals, but samples are often contaminated with iron(III) chloride, giving a yellow color.
Dysprosium(III) chloride (DyCl3), also known as dysprosium trichloride, is a compound of dysprosium and chlorine. It is a white to yellow solid which rapidly absorbs water on exposure to moist air to form a hexahydrate, DyCl3·6H2O. Simple rapid heating of the hydrate causes partial hydrolysis to an oxychloride, DyOCl.
Cobalt(II) chloride is an inorganic compound of cobalt and chlorine, with the formula CoCl
2. The compound forms several hydrates CoCl
2·nH
2O, for n = 1, 2, 6, and 9. Claims of the formation of tri- and tetrahydrates have not been confirmed. 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 compounds in the lab.
Copper(II) chloride is the chemical compound with the chemical formula CuCl2. The anhydrous form is yellowish brown but slowly absorbs moisture to form a blue-green dihydrate.
Phosphorus pentachloride is the chemical compound with the formula PCl5. It is one of the most important phosphorus chlorides, others being PCl3 and POCl3. PCl5 finds use as a chlorinating reagent. It is a colourless, water-sensitive and moisture-sensitive solid, although commercial samples can be yellowish and contaminated with hydrogen chloride.
Phosphorus trichloride is an inorganic compound with the chemical formula PCl3. A colorless liquid when pure, it is an important industrial chemical, being used for the manufacture of phosphites and other organophosphorus compounds. It is toxic and reacts readily with water to release hydrogen chloride.
Rhodium(III) chloride refers to inorganic compounds with the formula RhCl3(H2O)n, where n varies from 0 to 3. These are diamagnetic solids featuring octahedral Rh(III) centres. Depending on the value of n, the material is either a dense brown solid or a soluble reddish salt. The soluble trihydrated (n = 3) salt is widely used to prepare compounds used in homogeneous catalysis, notably for the industrial production of acetic acid and hydroformylation.
Iridium(III) chloride is the inorganic compound with the formula IrCl3. The anhydrous compound is relatively rare, but the related hydrate is useful for preparing other iridium compounds. The anhydrous salt is a dark green crystalline solid. More commonly encountered is the trihydrate IrCl3(H2O)3.
Terbium(III,IV) oxide, occasionally called tetraterbium heptaoxide, has the formula Tb4O7, though some texts refer to it as TbO1.75. There is some debate as to whether it is a discrete compound, or simply one phase in an interstitial oxide system. Tb4O7 is one of the main commercial terbium compounds, and the only such product containing at least some Tb(IV) (terbium in the +4 oxidation state), along with the more stable Tb(III). It is produced by heating the metal oxalate, and it is used in the preparation of other terbium compounds. Terbium forms three other major oxides: Tb2O3, TbO2, and Tb6O11.
Cobalt(III) fluoride is the inorganic compound with the formula CoF3. Hydrates are also known. The anhydrous compound is a hygroscopic brown solid. It is used to synthesize organofluorine compounds.
Antimony trichloride is the chemical compound with the formula SbCl3. It is a soft colorless solid with a pungent odor and was known to alchemists as butter of antimony.
Berkelium forms a number of chemical compounds, where it normally exists in an oxidation state of +3 or +4, and behaves similarly to its lanthanide analogue, terbium. Like all actinides, berkelium easily dissolves in various aqueous inorganic acids, liberating gaseous hydrogen and converting into the trivalent oxidation state. This trivalent state is the most stable, especially in aqueous solutions, but tetravalent berkelium compounds are also known. The existence of divalent berkelium salts is uncertain and has only been reported in mixed lanthanum chloride-strontium chloride melts. Aqueous solutions of Bk3+ ions are green in most acids. The color of the Bk4+ ions is yellow in hydrochloric acid and orange-yellow in sulfuric acid. Berkelium does not react rapidly with oxygen at room temperature, possibly due to the formation of a protective oxide surface layer; however, it reacts with molten metals, hydrogen, halogens, chalcogens and pnictogens to form various binary compounds. Berkelium can also form several organometallic compounds.
Molybdenum(III) chloride is the inorganic compound with the formula MoCl3. It forms purple crystals.
Chlorotrifluorosilane is an inorganic gaseous compound with formula SiClF3 composed of silicon, fluorine and chlorine. It is a silane that substitutes hydrogen with fluorine and chlorine atoms.
Lanthanide trichlorides are a family of inorganic compound with the formula LnCl3, where Ln stands for a lanthanide metal. The trichlorides are standard reagents in applied and academic chemistry of the lanthanides. They exist as anhydrous solids and as hydrates.
Berkelium(III) chloride also known as berkelium trichloride, is a chemical compound with the formula BkCl3. It is a water-soluble green solid with a melting point of 603 °C. This compound forms the hexahydrate, BkCl3·6H2O.
Cobalt compounds are chemical compounds formed by cobalt with other elements. In the compound, the most stable oxidation state of cobalt is the +2 oxidation state, and in the presence of specific ligands, there are also stable compounds with +3 valence. In addition, there are cobalt compounds in high oxidation states +4, +5 and low oxidation states -1, 0, +1.