Section 9.1
Using Chemical Equations
Objectives
1. To understand the information given in a balanced equation
2. To use a balanced equation to determine relationships
between moles of reactant and products
Section 9.1
Using Chemical Equations
A. Information Given by Chemical Equations
Stoichiometry – study of the quantitative relationships
between reactants and products in a chemical reaction.
Mg(s) + 2 HCl(aq) → MgCl2 (aq) + H2 (g)
Section 9.1
Using Chemical Equations
Mole Ratio
N2 + 3 H2  2 NH3
1 molecule N2 + 3 molecules H2  2 molecules NH3
1 mole N2 + 3 moles H2  2 moles NH3
1 dozen N2 + 3 dozen H2  2 dozen NH3
Section 9.1
Using Chemical Equations
Mole Ratios
2 Al2O3(l) → 4 Al(s) + 3 O2 (g)
How many moles of Aluminum can be produced from
13.0 moles of aluminum oxide?
 4 mol Al 
  26.0 mol Al
13.0 mol Al2O3  
 2 mol Al2O3 
Section 9.1
Using Chemical Equations
Mole ratios
2 Al2O3(l) → 4 Al(s) + 3 O2 (g)
1. If 26.0 moles of aluminum are produced in a
reaction, how many moles of oxygen will also be
produced?
2. How many moles of aluminum oxide are required to
produce 18.1 moles of aluminum?
3. If 23.0 moles of aluminum oxide react, how many
grams of Aluminum will be produced?