The Collaborative International Dictionary
Cobaltous
Cobaltous \Co*balt"ous\, a. (Chem.) Pertaining to, derived from, or containing, cobalt; -- said esp. of cobalt compounds in which the metal has its lower valence.
Cobaltous chloride, a crystalline compound, CoCl2, of a pale rose color when hydrous, blue when dehydrated. Its solution is used for a sympathetic ink, the writing being nearly colorless when dried in the air, owing to absorbed moisture, and becoming bright blue when warmed.
Wiktionary
cobaltous
a. (context chemistry English) Containing cobalt in oxidation state 2.
Usage examples of "cobaltous".
Among these activators are magnesium, manganous zinc, ferrous, cobaltous, and nickelous ions, as well as others.