1. Stoichiometry

2. Chemical equations relate:
Number of molecules required to react in the equation
Number of moles of reactants and products required for the reaction
In a balanced equation all parts are equal so we can use in conversion factors to change from one substance to another.

3. Using the equation below:
N2 + 3H2 → 2NH3
1molN2 = 3 molH2 = 2 molNH3
The mole ratio is used to change from one substance to another.

4. N2 + 3H2 → 2NH3
What is the mole ratio for N2 and NH3?
What is the mole ratio for H2 and NH3?

5. N2 + 3H2 → 2NH3
How many mol NH3 can be made from 3.2mol H2 if excess N2 is present?
How many mol N2 are needed to make mol NH3 if excess N2 is present?

6. 6Na + Fe2O3 → 3Na2O + 2Fe
How many mol Fe2O3 are required to completely react 4.04 mol Na?
How many mol Na2O can be made from mol Na if excess Fe2O3 is present?