Question

iron (iii) oxide is the main source of iron for the steel industry and is one of the main oxides of iron, along with the more rare iron (ii) oxide.
the formulas for iron (ii) oxide and iron (iii) oxide are, respectively
a. feo and fe₂o₃
b. fe₂o₂ and fe₃o₄
c. fe₂o and fe₃o₂
d. feo₂ and fe₂o₄

Explanation:

Ionic compounds are neutral, so the total positive charge from cations equals the total negative charge from anions. Oxygen has a -2 charge. For iron (II) oxide, iron has a +2 charge: one Fe²⁺ balances one O²⁻, giving FeO. For iron (III) oxide, iron has a +3 charge: two Fe³⁺ (total +6) balance three O²⁻ (total -6), giving Fe₂O₃.

Answer:

A. FeO and Fe₂O₃