What does a subscript indicate in a chemical formula?

Explanation:

A subscript is a number that is placed below an alphabet on the bottom right side.

For example, for molecule 2 is the subscript.

A subscript indicates the number of atoms present in a substance or molecule.

For example, in the subscripts indicate that there are two hydrogen atoms, one sulfur atom, and four oxygen atoms.

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.