If 5.02 moles of iron react with excess oxygen gas, how many moles of Fe2O3 can be produced?

The answer to your question is 2.51 moles of Fe₂O₃ will be formed.

Explanation:

Data

Moles of Fe = 5.02

O₂ = excess

Moles of Fe₂O₃ = ?

Process

1.- Write the balanced chemical reaction

                   4Fe  +  3O₂   ⇒    2Fe₂O₃

            Reactants    Elements   Products

                   4                Fe                4

                   6                O                 6

2.- Calculate the moles of Fe₂O₃ when react 5.02 moles of Fe using proportions.

                      4 moles of Fe 2 moles of Fe₂O₃

                      5.02 moles     x

                      x = (5.02 x 2) / 4

                      x = 10.04/4

                     x = 2.51 moles