Feb.8/2011:Limiting Reactants (Brian)

In chemical reactions, usually one chemical gets used up before the other
-The chemical used up first is called the limiting reactant
-Once it is used up the reaction stops
-L.R determines the quantity of products formed
-To find the L.R assume one reactant is used up, determine how
  much of this reactant is required

example:
Find the L.R when 2.8mol of H2 reacts with 1.25mol of O2
2H2+O2 -----> 2H2O
2.8 x 1 = 1.4 mol L.R or 1.25mol x 2 = 2.5
         2                                      1