Limiting Reactants Clark-Grubb Mansberger Yagel

Limiting vs. Excess Limiting Reactant- Excess Reactant- The reactant in a chemical reaction that limits the amount of product that can be formed. The reaction will stop when all of the limiting reactant is consumed. Excess Reactant- The reactant in a chemical reaction that remains when the reaction stops. The excess reactant remains because there is nothing left with which it can react.

Real Life Example… If there are only 8 car bodies, then only 8 cars can be made. Likewise with chemistry, if there is only a certain amount of one 
reactant available for a reaction, the reaction must stop when 
that reactant is consumed whether or not the other reactant has been used up.

When asked to solve for limiting reactant, solve for the theoretical yield in grams of one product for ALL reactants! #1 4 NH3+ 5 O2   4 NO(g) + 6 H2O A 23.8 grams sample of ammonia is mixed 
with 18.0 grams of oxygen.  Which is the 
limiting reactant and which is in excess? * The limiting REACTANT is the one which 
produced the smallest amount of product

#2 4 NH3+ 5 O2   4 NO(g) + 6 H2O A 46.2 grams sample of ammonia is mixed with 
26.8 grams of oxygen.  What is the theoretical mass of water that can be produced? * The limiting REACTANT is the one which 
produced the smallest amount of product

#3 When 45 g of oxygen reacts with 56 g of potassium, what is the theoretical yield in grams of potassium oxide? 4 K + O2 2 K2O