1. Chemical Reactions
Limiting Reagent

2. Stoichiometry A method of analyzing chemical equations
Basic steps include
Balanced chemical equation
Identify start and end
Convert start to mole (if needed)
Mole ratio
Convert end to needed unit

3. Limiting Reagent Another word for reactant is reagent
A limiting reagent limits the amount of product that can be formed in a reaction
Unless substances are combined in exact amounts according to the balanced equation, there will usually be a limiting reagent and a reagent in excess
Watch this video for an example.

4. Finding the Limiting Reagent
Predict amount of product formed based on amount of each reagent put into reaction. (2 stoichiometry conversions!)
Identify limiting reagent (the reagent that give gives you less product)
The other reagent is the excess reagent

5. How Much Excess? Once excess reagent is determined…
Complete another stoichiometric conversion
Limiting reagent →excess reagent (amount used)
Subtract amount used from original amount of excess put into reaction
The difference is the amount of excess reagent

6. Percent Yield
If you actually do the lab and isolate a product, you can determine a % yield
%𝑦𝑖𝑒𝑙𝑑= 𝑎𝑐𝑡𝑢𝑎𝑙 𝑦𝑖𝑒𝑙𝑑 𝑡ℎ𝑒𝑜𝑟𝑒𝑡𝑖𝑐𝑎𝑙 𝑦𝑖𝑒𝑙𝑑 x 100%