The valency of iron (Fe) in this equation is 2
While, the valency of chlorine is 1
Therefore, we know that iron wants to give away 2 electrons to attain octet configuration, and chlorine wants to get an electron to attain octet configuration.
Also while find the products the number of atoms is similar to the oppostie valency
Fe = 1 atom , Cl = 2 atoms
Which will form FeCl₂
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