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
Example Setup:
given chemical mass
1 mole of given chemical
moles of wanted chemical (from chemical equation)
molar mass of wanted chemical 1
molar mass of given chemical
moles of given chemical (from chemical equation)
1 mole of wanted chemical

4. Stoichiometry Set up: Other ways of doing stoichiometry: mass  moles
given chemical mass
1 mole of given chemical
moles of wanted chemical (from chemical equation) 1
molar mass of given chemical
moles of given chemical (from chemical equation)

5. Stoichiometry moles  mass moles  moles moles of given chemical
moles of wanted chemical (from chemical equation)
molar mass of wanted chemical 1
moles of given chemical (from chemical equation)
1 mole of wanted chemical
moles of
given chemical
moles of wanted chemical (from chemical equation) 1
moles of given chemical (from chemical equation)

6. Stoichiometry Alternative
D2UM2 Method
D – DIVIDE given by molar mass
D – DIVIDE given by mole coefficient
U – Move UNDER wanted
M – MULTIPLY by wanted mole
coefficient
M – MULTIPLY by wanted molar mass