Cobalt(II) sulfate hydrate (CoSO4•xH2O)-Crystalline

Characteristic

Cobalt(II) sulfate is any of the inorganic compounds with the formula CoSO₄·x(H₂O). Usually cobalt sulfate refers to the hydrate CoSO₄·7H₂O, which is one of the most commonly available salts of cobalt.

hemical formula:CoSO₄·x(H₂O)

Molar mass:154.996 g/mol (anhydrous);

                    173.01 g/mol (monohydrate);

                    263.08 g/mol (hexahydrate);

                   281.103 g/mol (heptahydrate)

Appearance: reddish crystalline (anhydrous, monohydrate);

                     pink salt (hexahydrate)

Odor:odorless (heptahydrate)

Density: 3.71 g/cm³ (anhydrous);

             3.075 g/cm³ (monohydrate);

             2.019 g/cm³ (hexahydrate);

             1.948 g/cm³ (heptahydrate)

Melting point 735 °C (1,355 °F; 1,008 K)

Solubility in water:anhydrous:36.2 g/100 mL (20 °C);38.3 g/100 mL (25 °C);84 g/100 mL (100 °C)

heptahydrate:60.4 g/100 mL (3 °C);67 g/100 mL (70 °C)

Solubility anhydrous:1.04 g/100 mL (methanol, 18 °C)

insoluble in ammonia:heptahydrate:54.5 g/100 mL (methanol, 18 °C)

Magnetic susceptibility (χ):+10,000·10−6 cm3/mol

Refractive index (nD):1.639 (monohydrate);1.540 (hexahydrate);1.483 (heptahydrate)

Crystal structure:orthorhombic (anhydrous);monoclinic (monohydrate)

Application

Cobalt(II) sulfate heptahydrate is used in the preparation of pigments, as well as in the manufacture of other cobalt salts, which is used in porcelains and glass. It is used in storage batteries and electroplating baths, sympathetic inks, and as an additive to soils and animal feeds.