No, mass is not converted in the reaction of iron and sulfur. This reaction is a chemical reaction, not a nuclear reaction. In chemical reactions, atoms are rearranged, but they are not created or destroyed.

Here's why:

* Law of Conservation of Mass: This fundamental law states that the total mass of the reactants in a chemical reaction must equal the total mass of the products.

* Iron and Sulfur: When iron (Fe) reacts with sulfur (S), they form iron sulfide (FeS). The atoms of iron and sulfur simply combine in a new arrangement.

* No Nuclear Changes: The reaction involves the sharing of electrons between the iron and sulfur atoms, but the nuclei of the atoms remain unchanged. Nuclear reactions are required for mass to be converted into energy (as described by Einstein's famous equation E=mc²).

In summary: The reaction of iron and sulfur is a chemical reaction where the total mass of the reactants (iron and sulfur) is equal to the total mass of the product (iron sulfide). There is no conversion of mass in this reaction.