What is the chemical formula for iron(III) oxide, a key component of thermite?

The chemical formula for iron(III) oxide is indeed Fe2O3. This compound consists of iron in the +3 oxidation state (indicated by the Roman numeral III) and oxygen. In this formula, there are two iron (Fe) atoms for every three oxygen (O) atoms, which reflects the typical stoichiometry of iron(III) ions combining with oxide ions to form a stable ionic compound.

Iron(III) oxide is a crucial component in thermite reactions, which involve the reduction of metal oxides using aluminum, resulting in a significant exothermic reaction that produces molten iron and other byproducts. The presence of iron in its +3 oxidation state indicates that it has lost three electrons, contributing to the compound's properties and reactivity.

Other formulas mentioned represent different compounds with varying iron to oxygen ratios and oxidation states. FeO, for example, is iron(II) oxide where iron has a +2 oxidation state, and Fe3O4 is a mixed iron oxide containing both Fe(II) and Fe(III) ions. Fe2O4 does not correspond to a standard oxidation state of iron and is not widely recognized in chemical nomenclature. Hence, Fe2O3 stands out as the proper representation