Sidney P. answered 05/25/21
Astronomy, Physics, Chemistry, and Math Tutor
Balance the reaction for mole ratios: 4 Fe + 3 O2 --> 2 Fe2O3.
For iron: (44.3g Fe) * (1 mole Fe /55.845g Fe) * (2 mole Fe2O3 /4 mole Fe) = 0.3966 mole Fe2O3.
For oxygen: (24.1g O2) * (1 mole O2 /32.00g O2) * (2 mole Fe2O3 /3 mole O2) = 0.5021 mole Fe2O3.
Take lower value of moles of product: (0.3966 mole Fe2O3) * (159.69g Fe2O3 /1 mole Fe2O3) = 63.3g Fe2O3.
Formula of limiting reagent: Fe.
Amount of excess reagent: (Δmole = 0.1055 mole Fe2O3) * (3 mole O2 /2 mole Fe2O3) * (32.00g O2 /1 mole O2) = 5.1g excess O2.