Finding the limiting reagents

The limiting reagent is the reactant that is completely used up in a reaction, and thus determines when the reaction stops. To find the limiting reagent in the reaction we can use two methods.

Method 1

1. Determine the balanced chemical equation for the chemical reaction
2. convert all given information into moles through use of molar mass as a conversion factor
3. calculate the mole ratio from the given information. Compare the calculated ration to the actual ratio
4. use the amount of limiting reactant to calculate the amount of limiting reactant to calculate the amount of product produced.
5. if necessary, calculate how much is left in excess of the non-limiting reagent

Method 2

1. Balance the chemical equation for the chemical reaction 
2. convert the given information into moles
3. use stoichiometry for each individual reactant to find the mass of the product produced
4. the reactant that produces a lesser amount of product is the limiting reagent 
5. the reactant that produces a larger amount of product is the excess reagent
6. to find the amount of remaining excess reactant, subtract the mass of excess reagent consumed from the total mass of excess reagent given

You can use either method to figure out limiting reagent problems and they both work equally well depending on which one you like to use.

here are some sights that may help
http://chemwiki.ucdavis.edu/Analytical_Chemistry/Chemical_Reactions/Limiting_Reagents
https://www.chem.tamu.edu/class/majors/tutorialnotefiles/limiting.htm