Answer
The limiting reactant determines the maximum amount of product that can be produced in a reaction. Excess reactant is any reactant left over after the reaction.
Work Step by Step
Any input to a reaction can be the limiting reaction. The number of atoms of each element in the reactants determines how much product can be produced. The limiting reactant is the one with the element that runs out first.
Excess reactant is any reactant that was not able to be a part of the reaction and remains in its original form.
