Does not react strongly as either oxidizing agents or reducing agents but such behavior is not impossible. The aqueous solutions are acidic. May catalyze organic reactions.
ChEBI: A hydrate that is the heptahydrate form of cobalt(2+) sulfate.
Literature sources indicate that Cobalt sulfate heptahydrate is nonflammable.
Air & Water Reactions
Water soluble. The resulting solution is acidic.
Crystallise it three times from conductivity water (1.3mL/g) between 100o and 0o depending on which hydrate is required. The heptahydrate crystallises below 44o and is efflorescent with m 97o . Between 44o and 70o the monoclinic hexahydrate CoSO4.6H2O m 41.5o is formed, and above 70o the monohydrate CoSO4.H2O m 71o is obtained. The pale reddish or lavender-coloured anhydrous salt is obtained by heating the hydrate above 250o, boiling with conc H2SO4 or heating with (NH4)2SO4).
Cobalt sulphate appears as pink or red crystals. It is stable, non-flammable, and hygroscopic and undergoes dehydration at 41°C and 71°C.
Pink to red monoclinic prismatic crystals or red granular solid. Odorless. Becomes anhydrous at 788°F.
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.