Which is a factor in determining the average atomic mass of an element?
1. atomic number of the most abundant isotope
2. relative abundance of each isotope
3. sum of atomic masses of all isotopes
4. product of atomic masses of all isotopes
5. arithmetic mean of atomic masses of the isotopes

answer:

the reaction is type of combination reaction.

explanation:

on the product side, there are 2 molecules of bonded to fe   which means one atom of fe are combined two molecules of . so, balanced chemical equation becomes :

this reaction follows the reaction type of combination reaction. a combination reaction is defined as chemical reaction in which reactants combines together to form a single product.