Final answer:
FeCl₃ reacts with the iron (Fe) part of the molecule, leading to a comproportionation reaction where Fe is oxidized and Fe3+ is reduced, forming Fe2+ in FeCl₂ with a specific stoichiometry.
Step-by-step explanation:
The reaction question pertains to the chemical interaction between iron (Fe) and iron(III) chloride (FeCl₃). FeCl₃ reacts primarily with the Fe part of the molecule. In the provided reaction Fe(s) + 2FeCl₃ (s) → 3FeCl₂ (s), iron is being oxidized from the elemental state to the Fe2+ oxidation state, while Fe3+ in the iron(III) chloride is being reduced to Fe2+. This is an example of a comproportionation reaction, where a single element in two different oxidation states reacts to form a species with an intermediate oxidation state.
The stoichiometry of the metal halide formed in such reactions is determined by the relative amounts of metal and halogen, as well as the strength of the halogen as an oxidizing agent. In this case, the stoichiometry is such that one iron atom reacts with two molecules of FeCl₃ to produce three molecules of FeCl₂.
Note that while fluorine typically forms fluoride-containing metals in their highest oxidation states, other halogens, such as chlorine in this reaction, may result in lower oxidation state compounds due to their varying oxidizing strengths.