The limiting reactant is the reactant that will limit the equation.
For example, I have 2N2 and H2O. In this situation, H2O would be the limiting reactant since there is only one atom, while N2 has two atoms.
Think of it like you're making peanut butter and jelly. You have 50 cans of peanut butter and only 10 jelly. Which means you can only make sandwiches using 10 jars of jelly and 10 jars of peanut butter.
