What is the compound name of chemical formula Fe2O3?
The correct answer and explanation is:
Correct Answer: Iron(III) oxide
Iron(III) oxide is the chemical compound with the formula Fe₂O₃. It consists of two iron (Fe) atoms and three oxygen (O) atoms. The Roman numeral (III) indicates that each iron atom has a charge of +3, meaning it is in the +3 oxidation state. This distinction is important because iron can also form other oxides, such as FeO (iron(II) oxide), where the iron has a +2 charge.
The naming of Fe₂O₃ follows the rules for naming ionic compounds containing transition metals. In this case, iron is a transition metal capable of forming multiple positive charges. Oxygen, a nonmetal, typically has a charge of -2. To balance the charges in Fe₂O₃, two iron ions with a +3 charge each (total +6) combine with three oxygen ions with a -2 charge each (total -6), resulting in a neutral compound.
Iron(III) oxide occurs naturally as the mineral hematite. It is a reddish-brown solid and is one of the main sources of iron used in steelmaking. It also gives rust its characteristic color when iron reacts with oxygen and moisture over time. In industry, iron(III) oxide is used as a pigment and polishing agent. It is sometimes referred to as ferric oxide, an older name still used in various applications.
Understanding the formula and name of Fe₂O₃ provides insight into chemical bonding, oxidation states, and how compounds are named systematically. This helps avoid confusion between compounds that contain the same elements but in different ratios or oxidation states, such as iron(II) oxide (FeO) versus iron(III) oxide (Fe₂O₃).