Iron(III) oxide reacts with carbon monoxide according to the equation: Fe₂O₃(s) + 3 CO(g) → 2 Fe(s) + 3 CO₂(g) A reaction mixture initially contains 22.55 g Fe₂O₃ and 14.78 g CO. Once the reaction has occurred as completely as possible, what mass (in g) of the excess reactant remains?

Key Concepts

Stoichiometry

Stoichiometry is the calculation of reactants and products in chemical reactions based on the balanced chemical equation. It allows us to determine the proportions of substances involved in a reaction, which is essential for identifying limiting and excess reactants. In this case, stoichiometry will help us calculate how much of each reactant is consumed and how much remains after the reaction.

Limiting Reactant

The limiting reactant is the substance that is completely consumed first in a chemical reaction, thus determining the maximum amount of product that can be formed. Identifying the limiting reactant is crucial for calculating the amounts of products and any excess reactants left over. In this reaction, we will need to find out which reactant, Fe2O3 or CO, limits the formation of iron and carbon dioxide.

Excess Reactant

The excess reactant is the substance that remains after the reaction has gone to completion, as it is not completely consumed. Understanding the concept of excess reactants is important for calculating how much of a reactant is left over after the reaction. In this scenario, once we identify the limiting reactant, we can determine the mass of the excess reactant that remains unreacted.