In what mass ratio is it necessary to take pure substances (iron and sulfur) so that they react with the formation

In what mass ratio is it necessary to take pure substances (iron and sulfur) so that they react with the formation of iron sulfide (||) completely, without residue?

The formula of iron (II) sulfide is FeS, since iron has a valence of 2 (indicated in the condition), and sulfur has a valence of 8-6 = 2 in second place. Since the substances have the same valence, the indices are not needed. Iron has an atomic mass = 56, and sulfur has 32, then you can make up the ratio 56:32, and reducing it, we get 7: 4.
Answer 7: 4 grams.