Which formula represents copper(i) oxide?
(1) cuo (3) cu2o
(2) cuo2 (4) cu2o2

Answer : The correct formula of copper(I) oxide is, (3)

Explanation :

Copper(I) oxide is an ionic compound because copper element is a metal and oxide element is a non-metal. The bond formed between a metal and a non-metal is always ionic in nature.

The nomenclature of ionic compounds is given by:

The charge on copper is (+1) and the the charge on oxide is (-2). The charges are not balanced.  The charges are balanced by the criss-cross method.

Hence, the formula of copper(I) oxide is,

answer///carbon;