Copper compounds (Topical Term)

Oxford dict. of chemistry, via Answers website, July 17, 2012 (cuprous compounds: Compounds containing copper in its lower (+1) oxidation state; e.g. cuprous chloride is copper(I) chloride (CuCl))

Copper compounds, via Copper Development Association website, July 17, 2012 (Common copper compounds for agricultural and chemical uses are: Anhydrous and monohydrated copper sulphate; Copper acetates; Cuprous oxide; Cupric oxide (black copper oxide); Cupric chloride; Copper oxychloride; Cuprous chloride; Cupric nitrate; Copper cyanide; Copper soaps; Copper naphthenate)

Interactive periodic table : a multimedia tour of the elements, via WWW, July 17, 2012: Cu (The two most common ions formed by copper are the +1 (cuprous) and +2 (cupric). The cuprous ion is the less stable of the two oxidation states and is easily oxidized. Therefore, any work done with copper(I) compounds must be carried out in an inert atmosphere; Most copper compounds are blue or green in color.)

Copper chemistry, via University of the West Indies at Mona, Jamaica Dept. of Chemistry website, July 17, 2012 (copper compounds; Copper exhibits a variety of compounds, many of which are coloured. The two principal oxidation states of copper are +1 and +2 although some +3 complexes are known. Copper(I) compounds are expected to be diamagnetic in nature and are usually colourless, except where colour results from charge transfer or from the anion; The copper(II) ion is usually the more stable state in aqueous solutions. Compounds of this ion, often called cupric compounds, are usually coloured.)