Cobalt(III) nitrate is an

inorganic compound In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemist ...

with the

chemical formula In chemistry, a chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, ...

Co(NO₃)₃.W. Levason and C. A. McAuliffe (1974): "Higher oxidation state chemistry of iron, cobalt, and nickel". ''Coordination Chemistry Reviews'', volume 12, issue 2, pages 151-184. It is a green, diamagnetic solid that sublimes at ambient temperature.

Structure

The compound is a molecular

coordination complex A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many ...

. The three bidentate

nitrate Nitrate is a polyatomic ion A polyatomic ion, also known as a molecular ion, is a covalent bonded set of two or more atoms, or of a metal complex, that can be considered to behave as a single unit and that has a net charge that is not zer ...

ligands give a distorted

octahedral In geometry, an octahedron (plural: octahedra, octahedrons) is a polyhedron with eight faces. The term is most commonly used to refer to the regular octahedron, a Platonic solid composed of eight equilateral triangles, four of which meet at ea ...

arrangement. The nitrate

ligand In coordination chemistry, a ligand is an ion or molecule (functional group) that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's electr ...

s are planar. With D₃

symmetry Symmetry (from grc, συμμετρία "agreement in dimensions, due proportion, arrangement") in everyday language refers to a sense of harmonious and beautiful proportion and balance. In mathematics, "symmetry" has a more precise definit ...

, the molecule is

chiral Chirality is a property of asymmetry important in several branches of science. The word ''chirality'' is derived from the Greek (''kheir''), "hand", a familiar chiral object. An object or a system is ''chiral'' if it is distinguishable from ...

. The Co-O bond lengths are about 190 pm long. The O-Co-O angles for the two oxygens in the same nitrate is about 68 degrees. The same geometry seems to persist in carbon tetrachloride solution.R. J. Fereday, N. Logan and D. Sutton (1969): "Anhydrous cobalt(III) nitrate: preparation, spectra, and reactions with some organic ligands". ''Journal of the Chemical Society A: Inorganic, Physical, Theoretical'', volume 1969, issue 0, pages 2699-2703.

Preparation and reactions

Cobalt(III) nitrate can be prepared by the reaction of

dinitrogen pentoxide Dinitrogen pentoxide is the chemical compound with the formula , also known as nitrogen pentoxide or nitric anhydride. It is one of the binary nitrogen oxides, a family of compounds that only contain nitrogen and oxygen. It exists as colourless ...

with

cobalt(III) fluoride Cobalt(III) fluoride is the inorganic compound with the formula . Hydrates are also known. The anhydrous compound is a hygroscopic brown solid. It is used to synthesize organofluorine compounds. The related cobalt(III) chloride is also known but ...

. It can be purified by vacuum sublimation at 40 °C.J. Hilton and S. C. Wallwork (1968): "The crystal structure of cobalt(III) nitrate", ''Chemical Communications'', volume 1968, issue 15, pages 871-871. E. Stumpp, G. Nietfeld, K. Steinwede, and K. D. Wageringel (1983) "Reaction of anhydrous metal nitrates with graphite". ''Synthetic Metals'', Evolume 7, issues 1–2, pages 143-151. Cobalt(III) nitrate oxidizes water, the initial green solution rapidly turns pink, with formation of cobalt(II) ions and release of

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...

. Cobalt(III) nitrate can be intercalated in

graphite Graphite () is a crystalline form of the element carbon. It consists of stacked layers of graphene. Graphite occurs naturally and is the most stable form of carbon under standard conditions. Synthetic and natural graphite are consumed on large ...

, in the ratio of 1 molecule for each 12

carbon Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with o ...

atoms.

References

Cobalt(III) compounds Nitrates {{Inorganic-compound-stub

Structure

Preparation and reactions

See also

References