To produce iron from ferric oxide or iron(III) oxide, ferric oxide is reacted with carbon monoxide in a chemical reaction that has the following equation:

Fe2O3 + CO --> Fe + CO2

This equation is not balanced and balancing the chemical equation gives:

Fe2O3 + 3CO --> 2Fe + 3CO2

This shows that for each mole of Fe2O3 three moles of carbon monoxide (CO) are required. The molar mass of Fe2O3 is 159.69 g/mole. 2.7 kg of Fe2O3 is equivalent to 2700/159.69 = 16.9 moles.

The reaction with carbon monoxide requires thrice the number of moles of carbon monoxide or approximately 50.7 moles.