Chapter 11 Outline – The Mole
I.
Measuring Matter (section 11.1)
A. Counting Particles
Q: How many do the following counting units equal? What would they
be used to count?
A: unit
# it means
example
Dozen
Pair
Trio
Six-pack
Ream
Gross
Q: What is a mole?
A:


In one mole of ANYTHING, there are 6.02 x 1023 representative
particles ( atoms, molecules, formula units, ions)
WOW, that is a lot. Let’s make sure we understand.
o 1 mole of pizza =
o 1 mole of cotton =
o 1 mole of water =
o 1 mole of gold =
Avogadro’s number =
Q: Who was Amedeo Avogadro?
A:
Q: What is the difference between a molecule, atom, and formula unit? p.
310
Fig. 11-2
A: molecule =
atom =
formula unit =
B. Converting Moles to Representative Particles and Representative Particles
to Moles
Q: What is a conversion factor?
A:
Show an example
1. Convert Moles to Representative Particles
1 mole =
representative particles (atoms or molecules
or formula units)
Q: How many molecules are in 4.2 moles of glucose (C6H12O6)
Do Practice Problems p. 311 # 1-3
1.
2.
3.
2. Convert representative particles to moles
 Use the exact same method a converting moles to
representative particles, just use the inverse of the conversion
factor.
Do Practice Problems p. 312 # 4
4. a.
b.
c.
d.
II.
Mass and the Mole (section 11.2)
A. The Mass of a Mole
Q: What is the difference between atomic mass and mass number?
A: atomic mass=
Mass number =
Define molar mass =
Molar mass is numerically equal to the
.
Let’s Practice:
Element
atomic mass
molar mass
C
Sb
Br
 How easy, the molar mass is the same # as the atomic mass on the
periodic table. BUT, with units of g/mol not amu.
Molar mass of compounds (section 11.3)
 Add up the masses from the periodic table for each atom of each
element.
Let’s Practice:
1. molar mass of glucose, C6H12O6 =
2. molar mass of carbon dioxide =
Do Practice Problems p. 322 #25
25.
B. Using Molar Mass
Read p. 314-315
1. Use molar mass to convert moles to mass(grams) and mass to
moles
Ex. How many grams of gold are in .215 moles of gold?
Step 1: determine the molar mass of the element (this is the
conversion factor)
Step 2: start with what was given
Step 3: Plug in the conversion factor (molar mass)
Do Practice Problems p. 316 #11
11 a.
b.
c.
d.
Do Practice Problems p. 316 #12
12 a.
b.
c.
d.
Do Practice Problems p. 323 # 27-29
27.
28.
29.
Do Practice Problems p. 324 # 30a-d
30 a.
b.
c.
d.
2. Convert mass to atoms (massmoles atoms)
Step 1: must convert mass to moles FIRST.
Step 2: once you have moles, convert to atoms using Avogadro’s #
as your conversion factor.
Conversion factor =
Ex. How many atoms of NH3 are in 62 g of NH3
Convert mass  moles
Convert moles  atoms

You can do this all in one problem.
Do Practice Problems p. 318 #13 a-d
13 a.
b.
c.
d.
3. Convert atoms to mass (atomsmoles mass)
 Same as mass to atoms, just in reverse.
Do Practice Problems p. 318 #14 a-d
14 a.
b.
c.
d.
SUMMARY
Converting:
1. moles  representative particles (i.e. atoms, molecules, formula units)
given moles x
6.02 x 10 23 representative particles
1 mole
2. moles  mass (grams)
given moles x molar mass (g)
1 mol
3. mass(grams)  moles
given mass (g) x 1 mol
.
molar mass (g)
4. mass (grams)  atoms
(mass  moles atoms)
given mass (g) x 1 mol
x
molar mass (g) x
6.02 x1023 atoms
1 mol
5. atoms  mass (grams)
(atoms  moles  mass)
given atoms
III.
x 1 mol
x
6.02 x 1023 atoms x
Moles of Compounds (section 11.3)
A. Chemical Formulas and the Mole
1. The subscript tells you how many
mole of the compound.
molar mass (g)
1 mol
of atoms are in 1
Ex.
In 1 mol C6H12O6 there are 6 moles of C atoms.
In 1 mol C6H12O6 there are
of H atoms
In 1 mol C6H12O6 there are
of O atoms
Write each of the above as a ratio (conversion factor)
These would be then called mole ratios.
2. Using mole ratios (convert moles moles)
Ex. Determine the # of moles of C in 3 mol of sucrose ( C12H22O11)
Step 1: determine the mole ratio
Step 2: start with the given
Step 3: plug in the mole ratio (conversion factor), solve
Do Practice Problems p. 321 # 20-22
20.
21
22.
B. Convert the Mass of a Compound to Representative Particles
(mass  moles  representative particles)
Ex.