The chemical reaction you've written is the formation of iron(II) chloride from iron and chlorine gas. The balanced equation for the reaction is:

\[
\text{Fe} + \text{Cl}_2 \rightarrow \text{FeCl}_2
\]

In this reaction, one atom of iron (Fe) reacts with one molecule of chlorine gas (Cl₂) to produce one formula unit of iron(II) chloride (FeCl₂).

If you need more information or have specific questions about this reaction, feel free to ask!