1. Stoichiometry
If you had some eggs, flour, and sugar lying around the house and you wanted to make a cake, what would you do?
How much cake could you make with the ingredients you already have?
If you had to make 5 cakes, what would you do?
How much material (eggs, flour, sugar) do you need to make 5 cakes?

2. Stoichiometry
-Atoms are neither created nor destroyed in a chemical reaction.
-It is possible to calculate the mass of any one of the products or of any one of the reactants if the mass of just one reactant or product is known using a balanced equation.
-the coefficients in the balanced chemical equation are mole quantities, not masses.

3. Stoichiometry
2 H2 + O2 → 2 H2O
Ex: Given the equation above, how many grams of water will be obtained by combining 5.0 grams of hydrogen gas with an excess of oxygen gas?
mass  mass
known  known  unknown  unknown
mass moles moles mass
Example Setup:
Mole Ratio
(always present)

4. Stoichiometry Other ways of doing stoichiometry: mass  moles
known mass  known moles  unknown moles
moles  mass
known moles  unknown moles  unknown mass

5. known moles  unknown moles
Stoichiometry
moles  moles
known moles  unknown moles