Question

Prior to the use of the Stock system for naming transition metal cations, the ion Cu2+ was commonly known as the ______ ion.

Answer 1

Before the Stock system, the ion Cu2+ was known as the cupric ion, with 'cupric' indicating the higher charge state of the copper ion.

Step-by-step explanation:

Prior to the use of the Stock system for naming transition metal cations, the ion Cu2+ was commonly known as the cupric ion. In the older naming system, often referred to as the common system, transition metals with two common cations were given names using the suffixes -ic and -ous. The -ic suffix was used for the cation with the higher charge, in this case, Cu2+ as 'cupric', whereas the -ous suffix was used for the lower charge, such as Cu+ for 'cuprous'. The Stock system uses Roman numerals to indicate the charge, so Cu2+ is named copper(II) ion.