1.
Illustrate the equation for photosynthesis.
Atomic
Structure
Chemical
Bonding
Chemical
Reactions
Stoichiometry
Solutions
Acid/Base
Chemistry
Kinetic
Molecular
Theory
Learning Target: Identify and solve different types of stoichiometry
problems by balancing chemical equations.
By: Coach Lightfoot

Stoichiometry: Calculations of quantities in
chemical reactions. BALANCING EQUATIONS!
 Indicates how much substance you end with based on
how much you started with.
▪ A + 2B  AB2
▪ A3B2CD  3A + 2B + C + D
▪ A2 + 3B2  2AB3
▪ A2 + B2  2AB

Atoms:
 # of atoms in reactant = # of atoms in product.

Molecules:
 # of molecules in reactant = # of molecules in product.

Moles: (1 dozen = ?; 1 pair = ?; 1 mole = 6.0 x 1023)
 A balanced equation indicates the # of moles in the
reactants and products.
 N2(g) + 3H2(g)  2NH3(g)
 One molecule of N2 reacts with three H2 molecules to
yield 2 molecules of NH3.
1.
N2(g)
+
H2(g) 
2.
H2S(g) + O2(g) 
3.
CO2(g) +
H2O(l) 
NH3(g)
SO2(g) + H2O(g)
C6H12O6(aq) + O2(g)

Isoamyl acetate is the molecule found in
banana flavor. In the production of
banana flavor, so many molecules
isoamyl acetate is produced that the
molecule is also used to make air
fresheners and artificial leather!

Identify the reaction type of each reaction and
balance.
1. H2 + I2  HI
2. Na + Cl2  NaCl



What is stoichiometry?
Explain the relevance of balancing equations.
How much is a mole?

Read Section 12.1

Indicate the reaction type, the amount of
molecules and the amount of moles of each
reactant and product:
Learning Target: Identify and solve different types of
stoichiometry problems using units of moles and
masses of reacting particles.
By: Coach Lightfoot

Used to convert moles to mass and mass to
moles using mole ratios!

The conversion factor derived from the
coefficients of a balanced equation
interpreted using moles.
1 mole of H2 WRONG!!!
1 mol of H2
WRONG!
1 mol H2
1mol H2
ALMOST!!!
RIGHT!!!
Converting moles to moles!
 N2(g)
+
3H2(g)  2NH3(g)
 Calculate moles of NH3 produced when
0.60mol N2 reacts with H2.

Converting moles to mass!
 N2(g)
+
3H2(g)  2NH3(g)
 Calculate number of grams of NH3(g)
produced by the reaction of 5.40g of H2(g)
with an excess of nitrogen.


mA  nB

5C(s) + 2SO2(g)  CS2(l) + 4CO(g)

Calculate moles of CS2 produced when
2.7mol C reacts.

Moles can be converted to any other unit
measurement related to the unit mole.

Study your notes!!!
Learning Target: Indicate limiting reagents in chemical rxns and
calculate percent yields.
By: Coach Lightfoot

Take 2min: What things are the most
important to consider when cooking?

Limiting Reagent: Substance in chemical rxn
that used up completely.
 Rxn will proceed until the limiting reagent is used
up.

Excess Reagent:…?



Theoretical Yield: The amount of product that is
calculated to be produced in a rxn.
Actual Yield: …?
Percent Yield: Ratio of actual yield and theoretical
yield expressed as a percent.

Percent yield is a measure of the efficiency of a rxn
carried in the lab.
 Ex.
▪
▪
▪
▪
▪

…
…
…
…
…
Take 2min: What factors can cause actual yield to
be less than the theoretical yield?

Read Section 12.3!
 Test Friday!
Learning Target:
By: Coach Lightfoot


Limiting Reagent
Excess Reagent
Limiting Reagent
Excess Reagent
Reactant that’s being used up!
Reactant that’s not being used up!


Study for the Test!
Quizzes and Worksheets!
Theoretical Yield
Actual Yield
Maximum amount of product that
The amount of product that is
could be formed from given amounts actually formed when the rxn is
of reactants.
carried out in the lab.