Cobalt Metahydroxide

Cobalt Metahydroxide
Cobalt Metahydroxide
Are common
Systematic ; name	Cobalt Metahydroxide
Traditional names	cobalt (III) hydroxide
Chem. formula	CoO (OH)
Physical properties
condition	black crystals
Molar mass	91.94 g / mol
Density	amorphous. 4.29 ; krist. 4.72-4.90 g / cm³
Hardness	3-5 (on the Mohs scale )
Thermal properties
Enthalpy of Education	-435 kJ / mol
Classification
Reg. CAS number
PubChem
Reg. EINECS number
Smiles
Inchi
ChemSpider
Security
MPC	0.5 mg / kg

Cobalt metahydroxide is an inorganic compound, cobalt metal hydroxide with the formula CoO (OH), a dark brown amorphous precipitate or black crystals insoluble in water.

Content

Getting

In nature, the heterogenite mineral CoO (OH) is found with various impurities.

Oxidation of cobalt (II) hydroxide :

{\mathsf {4Co(OH)_{2}+O_{2}\ {\xrightarrow {100^{o}C,p}}\ 4CoO(OH)\downarrow +2H_{2}O}}

{\ displaystyle {\ mathsf {4Co (OH) _ {2} + O_ {2} \ {\ xrightarrow {100 ^ {o} C, p}} \ 4CoO (OH) \ downarrow + 2H_ {2} O}} }

Oxidation of a soluble salt of bivalent cobalt in an alkaline medium:

{\mathsf {4CoCl_{2}+O_{2}+16(NH_{3}\cdot H_{2}O)\ {\xrightarrow {}}\ 4CoO(OH)\downarrow +8NH_{3}\uparrow +8NH_{4}Cl+10H_{2}O}}

{\ displaystyle {\ mathsf {4CoCl_ {2} + O_ {2} +16 (NH_ {3} \ cdot H_ {2} O) \ {\ xrightarrow {}} \ 4CoO (OH) \ downarrow + 8NH_ {3} \ uparrow + 8NH_ {4} Cl + 10H_ {2} O}}}

Alkaline precipitation from a solution of salts of trivalent cobalt:

{\mathsf {CoF_{3}+3NaOH\ {\xrightarrow {}}\ CoO(OH)\downarrow +3NaF+H_{2}O}}

{\ displaystyle {\ mathsf {CoF_ {3} + 3NaOH \ {\ xrightarrow {}} \ CoO (OH) \ downarrow + 3NaF + H_ {2} O}}}

Physical Properties

Cobalt metahydroxide forms black crystals of trigonal syngony , space group R 3 m , cell parameters a = 0.2851 nm, c = 1.3150 nm, Z = 3. At high temperature and pressure, it transforms to another modification of rhombic syngony , space group P bnm , cell parameters a = 0.4353 nm, b = 0.9402 nm, c = 0.2840 nm, Z = 4.

Not soluble in water, p PR = 42.60.

Chemical Properties

Decomposes on heating:

{\mathsf {12CoO(OH)\ {\xrightarrow {150^{o}C}}\ 4Co_{3}O_{4}+O_{2}+6H_{2}O}}

{\ displaystyle {\ mathsf {12CoO (OH) \ {\ xrightarrow {150 ^ {o} C}} \ 4Co_ {3} O_ {4} + O_ {2} + 6H_ {2} O}}}

^[one]

With concentrated acids, it manifests itself as an oxidizing agent:

{\mathsf {2CoO(OH)+6HCl\ {\xrightarrow {}}\ 2CoCl_{2}+Cl_{2}+4H_{2}O}}

{\ displaystyle {\ mathsf {2CoO (OH) + 6HCl \ {\ xrightarrow {}} \ 2CoCl_ {2} + Cl_ {2} + 4H_ {2} O}}}

{\mathsf {4CoO(OH)+4H_{2}SO_{4}\ {\xrightarrow {100^{o}C}}\ 4CoSO_{4}+O_{2}+6H_{2}O}}

{\ displaystyle {\ mathsf {4CoO (OH) + 4H_ {2} SO_ {4} \ {\ xrightarrow {100 ^ {o} C}} \ 4CoSO_ {4} + O_ {2} + 6H_ {2} O} }}

{\mathsf {4CoO(OH)+8HNO_{3}\ {\xrightarrow {80^{o}C}}\ 4Co(NO_{3})_{2}+O_{2}+6H_{2}O}}

{\ displaystyle {\ mathsf {4CoO (OH) + 8HNO_ {3} \ {\ xrightarrow {80 ^ {o} C}} \ 4Co (NO_ {3}) _ {2} + O_ {2} + 6H_ {2 } O}}}

Notes

↑ Tretyakov Yu.D. Inorganic chemistry. Chemistry of the elements. Volume 1. - 2nd. - Moscow State University; IKC "Akademkniga", 2007. - S. 442. - 537 p.

Literature

Chemical Encyclopedia / Editorial Board: Knunyants I.L. et al. - M .: Soviet Encyclopedia, 1990. - T. 2. - 671 p. - ISBN 5-82270-035-5 .
Lidin R.A. and other Chemical properties of inorganic substances: Textbook. manual for universities. - 3rd ed., Rev. - M .: Chemistry, 2000 .-- 480 p. - ISBN 5-7245-1163-0 .
Ripan R., Chetyanu I. Inorganic chemistry. Chemistry of metals. - M .: Mir, 1972. - T. 2. - 871 p.

[1] Tretyakov Yu.D. Inorganic chemistry. Chemistry of the elements. Volume 1. - 2nd. - Moscow State University; IKC "Akademkniga", 2007. - S. 442. - 537 p.

Cobalt Metahydroxide
Are common
Systematic name	Cobalt Metahydroxide
Traditional names	cobalt (III) hydroxide
Chem. formula	CoO (OH)
Physical properties
condition	black crystals
Molar mass	91.94 g / mol
Density	amorphous. 4.29 krist. 4.72-4.90 g / cm³
Hardness	3-5 (on the Mohs scale )
Thermal properties
Enthalpy of Education	-435 kJ / mol
Classification
Reg. CAS number
PubChem
Reg. EINECS number
Smiles
Inchi
ChemSpider
Security
MPC	0.5 mg / kg