Question

The balanced equation for the reaction of iron (III) oxide with carbon monoxide to produce carbon
dioxide and iron metal is given below.
Fe2O3 (s) + 3 CO (g) --> 2 Fe (s) + 3 CO2 (g)
Using the balanced equation, determine the mass of iron metal (Fe(s)) in grams that can be made if
this reaction is performed using 225.3 grams of iron (III) oxide (Fe2O3) and 200.1 grams of carbon
monoxide.

Answer 1

Molar mass of Fe2O3 = 55.845 * 2 + 3 * 16 = 159.69 gm/mol

Number of moles of Fe2O3 = 225.3/159.69 = 1.4108 moles

Molar mass of CO = 12 + 16 = 28 gm/mol

Number of moles of CO = 200.1/28 = 7.1464 moles

1 mole of Fe2O3 requires 3 moles of CO, hence 1.4108 moles of Fe2O3 will require 4.3 moles of CO

Hence Fe2O3 is the limiting reagent in the reaction

1 mole of Fe2O3 gives 2 moles of Fe metal

Moles of Fe metal = 1.4108 * 2 = 2.8216 moles

Molar mass of Fe = 55.845 gm/mol

Mass of Fe produced in the reaction = 2.8216 moles * 55.845 gm/mol = 157.57 grams