Cobalt blue monoxide

Sulphuric acid (concentrated). Widely used in desiccators. Suitable for drying bromine, saturated hydrocarbons, alkyl and aryl halides. Also suitable for drying the following gases hydrogen, nitrogen, carbon dioxide, carbon monoxide, chlorine, methane and paraffins. Unsuitable for alcohols, bases, ketones or phenols. Also available with an indicator (a cobalt salt, blue when dry and pink when wet) under the name Sicacide (from Merck) for desiccators. 

The treatment of diorganozincs or organozinc halides with cobalt bromide in THF NMP mixtures provides blue solutions of organocobalt reagents, which have a half-life of several hours at -20 °C.25,26 Carbonylation reactions with these new cobalt reagents proceed well simply by bubbling carbon monoxide... 

Thenard A process for making white lead pigment (basic lead carbonate) by boiling litharge (lead monoxide) with lead acetate solution and passing carbon dioxide gas into the suspension. L.J. Thenard (1777 to 1857) was an eminent French chemist, more famous for his invention of Thenard s blue (cobalt aluminate). 

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