What is the ionic compound name for Fe2O3?
The correct answer and explanation is:
Correct Answer: Iron(III) oxide
Iron(III) oxide is an ionic compound with the chemical formula Fe₂O₃. It consists of iron (Fe) and oxygen (O) atoms. The Roman numeral (III) in the name indicates the oxidation state of iron in this compound, which is +3. Each oxygen ion (oxide ion) has a charge of -2, so to balance the charges and form a neutral compound, two iron ions (each with a +3 charge) are needed for every three oxide ions (each with a -2 charge).
This results in a total positive charge of +6 (from two Fe³⁺ ions) and a total negative charge of -6 (from three O²⁻ ions), making the compound electrically neutral. The formula Fe₂O₃ reflects this balance.
Naming ionic compounds follows specific rules. The metal (cation) is named first, followed by the non-metal (anion) with its ending changed to “-ide.” However, when a transition metal like iron can form more than one possible charge, the specific charge is indicated with a Roman numeral in parentheses. Iron can form +2 or +3 oxidation states. In this case, iron is in the +3 state, so the correct name is Iron(III) oxide.
Iron(III) oxide is commonly found in nature as hematite, a primary ore of iron. It appears as a reddish-brown solid and is often used in pigments and as a source of iron in steel manufacturing. It is also responsible for the reddish color of rust when iron reacts with oxygen and water. The formation and naming of such compounds are critical in understanding the properties, behaviors, and interactions of materials in chemical and industrial processes.