2 Eggs + 4 Bacon + 1 OJ + 2 Toast  1 Breakfast
Learning Goals
0 Describe the types of relationships
indicated by a balanced chemical
equation.
0 State the mole ratios from a
balanced chemical equation.
Particle and Mole Relationships
0 Chemical reactions stop when one of
the reactants is used up.
0 Stoichiometry is the study of
quantitative relationships between the
amounts of reactants used and
amounts of products formed by a
chemical reaction.
Particle and Mole Relationships
0 Using stoichiometry, we can:
0 Predict the amounts of products that
form in a chemical reaction based on
the amounts of reactants
0 Predict how much of the reactants
are necessary to form a given
amount of product
Particle and Mole Relationships
0 Predict how much one reactant is
required to completely react with
another reactant.
Example
0 Interpret the equation for the combustion
of propane (C3H8) in terms of
representative particles, moles, and mass.
C3H8 + 5O2  3CO2 + 4H2O
Particle and Mole Relationships
0 A mole ratio is a ratio between the
numbers of moles of any two
substances in a balanced equation.
0 The number of mole ratios that can be
written for any equation is (n)(n – 1)
where n is the number of species in
the chemical reaction.
Practice
0 Determine all possible mole ratios
for the following chemical
equations. Balance the equations if
needed.
Practice
0
Al(s) +
O2(g) 
Al2O3(s)
Practice
0
Fe(s) +
H2O (l) 
Fe3O4(s) +
H2(g)