Nomenclature
CAS number: 10124-43-3
CoO
4S; mol wt 155.00.
Co 38.02%, O 41.29%, S 20.69%.
CoSO
4.
Description and references
Hexahydrate occurs in nature as the mineral bieberite. Prepn: Clark et al., J. Am. Chem. Soc. 42, 2483 (1920); Hammel, Ann. Chim. 11, 247 (1939); Gmelins, Cobalt (8th ed.) 58, (part
A) 324-336 (1932) and supplement, 628-647 (1961). Review: de Bie, Doyen, Cobalt 15, 3-13; 16, 3-15 (1962).
Properties
Red to lavender dimorphic, orthorhombic crystals.
d425 3.71. Stable to 708°. Dissolves slowly in boiling water.Derivative
Monohydrate.
Properties
Rose-colored, monoclinic crystals. Structure
reported to be Co(H2SO5). d425 3.08. Dissolves
slowly in boiling water.Derivative
Heptahydrate.
Nomenclature
CAS number: 10026-24-1
Properties
Pink to red monoclinic, prismatic crystals. On
heating dehydrates to the hexahydrate (monoclinic, prismatic crystals)
at 41.5°, and to the monohydrate at 71°. d425 2.03. Sol in water;
slightly sol in methanol, ethanol.Caution
Cobaltous sulfate is reasonably
anticipated to be a human carcinogen: Report
on Carcinogens (PB2005-104914, 2004) p III-70.Use
Usual source of water-soluble cobalt since it is
the most economical and it shows less tendency to deliquesc or dehydrate
than the chloride or nitrate. Used in storage batteries; in Co-electroplating
baths; as drier for lithographic inks, varnishes; in ceramics, enamels,
glazes to prevent discoloring; in Co pigments for decorating porcelain.