Iron reacts with sulfur to form iron sulfide. If 60 grams of iron reacts with sulfur to produce 90 grams of iron sulfide, how much sulfur has been used in the chemical reaction?

34.44 g.

Explanation:

The balanced equation for the reaction is:Fe + S → FeS,It is clear that 1.0 mol of Fe reacts with 1.0 mol of S to produce 1.0 mol FeS.We need to calculate the no. of moles of 60 grams of iron and 90 grams of iron sulfide:no. of moles of Fe = mass/atomic mass = (60.0 g)/(55.845 g/mol) = 1.074 mol.no. of moles of FeS = mass/molar mass = (90.0 g)/(87.91 g/mol) = 1.024 mol.∵ Fe reacts with S with (1: 1) molar ratio.∴ The no. of moles of S needed to react with Fe is 1.074 mol.∴ The no. of grams of S needed = no. of moles x molar mass = (1.074 mol)(32.065 g/mol) = 34.44 g.