Cuprous

Part of speech: adjective

Pronunciation: /ˈkjuːpɹəs/

Definitions

1. Pertaining to a specific oxidation state of copper, this term denotes compounds that contain the metal in its +1 oxidation form and highlight its unique chemical behaviors
2. This adjective characterizes substances featuring copper in a +1 oxidation state, often influencing their reactivity and interactions
3. Referring to a subtype of copper compounds, this term indicates those in which the metal exhibits a +1 oxidation state, thereby affecting their chemical properties and applications

Etymology: "Cuprous" is a straightforward chemical coinage. It is built from the Latin "cuprum," meaning copper, with the adjectival suffix "-ous," which English has long used to name a substance in a lower proportion of its element. Chemists applied the pattern to copper in the same way that "ferrous" was formed from Latin "ferrum" for iron. The contrast is the key to the word's logic. In chemistry, "cuprous" describes compounds in which copper has the lower of its two common ionic charges, Cu+, while "cupric" describes those with the higher charge, Cu2+. The "-ous" ending therefore marks the less oxidised form of the metal, a convention that lets a chemist tell cuprous oxide from cupric oxide at a glance.