Check for Understanding
The Mole
Mole Music Video
 http://www.youtube.com/watch?v=oIkC7SRqXP0
The Mole &
Avogadro’s Number
NA =
23
6.02x10
http://ed.ted.com/lessons/daniel-dulek-how-big-is-a-mole-not-the-animal-the-other-one
Today’s Objective
1) To define the mole.
2) To apply Avogadro’s number to convert
between moles and particles.
Counting Particles
Scientists Counting Unit
 Since atoms are so small, it is hard to count
individual atoms.
 To solve this problem, chemists count by moles.
 Moles: SI unit for measuring the amount of a
substance.
One mole of
Carbon
Mole Continued
 One mole of anything contains
6.02 x 1023 “particles”
 Particles can be atoms, ions,
molecules, electrons, formula units, etc.
Avogadro’s Number: 6.02x1023 = 1 mole
602,200,000,000,000,000,000,000
How Big is Avogadro’s Number?
 One mole of rice grains
 One mole of sheets of
paper stacked one on top of
the other would reach
beyond the solar system.
 One mole of basketballs
could create a new planet
the size of the earth.
would cover the land
masses of Earth in a depth
of 75 meters.
 If you had a mole of
pennies and gave away 1
million dollars of it
(100,000,000 pennies) a day
to everyone in the world it
would take you more than
3000 years to distribute all
your money.
Conversions with Avogadro’s
Number
1. Start with what you know.
2. Use the following conversion factor:
6.02 x 1023 particles
1 mole
3. Cancel units.
4. Solve (preform the math).
“Mole Map”
Practice Conversions:
Moles to Particles
1. Determine how many particles of sucrose are
in 3.50 moles of sucrose.
2. Determine the number of atoms in 2.50 mol of
Zn.
Practice Conversions:
Moles to Particles
3. Given 3.25 mol AgNO3, determine the number
of formula units.
4. Calculate the number of molecules in 1.15 mol
of water.
Warm-Up
Calculate the number of molecules in 1.15 mol of
water.
“Mole Map”
Practice Conversions:
Particles to Moles
1. How many moles are in 5.75x1024 atoms Al?
Practice Conversions:
Particles to Moles
2. How many ATOMS are in 3.75x1024 molecules
of CO2?
3. How many moles are in 2.50x1020 atoms of
Fe?
 Mole Conversion Worksheet
Practice, Practice, Practice
Check for Understanding
 1.5 moles Cu = ________ atoms Cu
 8.51 x 1023 S = ________ moles S
Solutions:
 9.0 x 1023
 1.41
Molar Mass and
Conversions
Adding Mass-Mole and Mole-Mass
Finally, put it all together and what do you get?!
Today’s Objective
1. I can calculate the molar mass of a
compound.
2. I can convert between mass, moles, and
particles using the correct ratios and
conversion factors.
Molar Mass
 Molar Mass: mass in grams of one mole of a
pure substance.
 Units = g/mol
 To calculate molar mass you must find the
atomic mass (Units = g).
Ex: Find the atomic mass of Al.
Ex: Find the atomic mass of O2.
Ex: Find the atomic mass of CH4.
* To change atomic mass to molar mass just
put the answer (g) over moles.
Mole-Mass Conversions
Conversion Factor:
Mass (g)
Moles
P. Table
1
Ex: While working in a Chemistry lab, Gary needs 3.00
moles of Mn for a chemical reaction. How much Mn does
Gary need to mass?
Practice with Mole-Mass
Conversions
 Determine the moles in
each of the following:

Determine the mass in
grams of each of the
following:
4. 25.5 g Ag
1.
3.57 mol Al
5. 125 g Zn
1.
42.6 mol Si
6. 1.45 kg Fe
1.
3.45 mol Co
Mass-Atoms Conversions
 This involves two conversions.
 Conversion #1: Mass to moles
 Conversion #2: Moles to particles
Mass
Moles
“Particles”
(g)
1
6.02x1023
 Ex: How many atoms of gold are in a pure
gold nugget having a mass of 25.0 g?
Practice Mass-Atom
Conversions
How many atoms are in
the following samples?
1.
55.2 g Li
2.
0.230 g Pb
3.
45.6 g Si
Reverse It…
Atoms-Mass Conversions
 This involves two conversions.
 Conversion #1: particles to moles
 Conversion #2: moles to grams.
Mass
Moles
“Particles”
(g)
1
6.02x1023
REVERSE IT….
Practice Atom-Mass Conversions
How many grams are in the following samples?
4. 6.02 x 1024 atoms Bi
5. 3.40 x 1022 atoms He
6. 1.50 x 1015 atoms U
Tie up your shoes its…
PRACTICE TIME!!!
Mole Conversion Worksheet
Mole Music Video
 http://www.youtube.com/watch?v=oIkC7SRqXP0