Discussion: The Mole
Objective: To understand the
mole concept and how it is related
to the more familiar dozen.
The Dozen
• How do you convert a number like 54 to
dozen?
• we divide by 12
• How do we convert dozens to numbers?
• Multiply by 12
Counting atoms
• How many atoms are there in a single
molecule of
The dozen is not used
to measure atoms
• Why would we not measure atoms in
dozen?
• They are to small
• The quantity used to express how many in
atoms is the mole.
• It is equal to 6.02 x 1023
6.02 x 1023
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•
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Which, if not written in scientific notation is
Mole = 602,000,000,000,000,000,000,000
Dozen = 12
Dozen = 1.2 x 101
Mole = 6.02 x 1023
How many BB are in 2.5 dozen?
• If we wanted to find the number of
baseballs in 2.5 dozen we would
• multiply _____ by _____ = ______
How many atoms are
in 2.5 moles of sodium?
• If we wanted to find the number of atoms
of sodium in 2.5 moles we would
• Multiply 2.5 by 6.02 x 1023 = 1.505 x 1024
How many atoms are
in 0.5 moles of calcium?
• 0.5 x 6.02 x 1023 = 3.01x 1023
• Another way
• 0.5 mol
Convert 5.6 x 1023 molecules of
oxygen to moles
• 5.6 x 1023 molecules O2
• 5.6 x 1023
How to find the mass of
one mole of an element
• To find the mass of one
mole of sodium we look on
the periodic table.
• 1.00 mole Na = 23.0 grams
• 4.2 moles
• 4.2 x 23 = 96.6
Calculate the formula mass
of the compounds below
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•
•
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CuCO3 63.5 + 12 + (3 x 16) = 123.5
Ba(NO3)2 = 137.3 + 2 x 14 + 6 x 16 =
Ca3(PO4)2
Sodium chloride
Iron(III) oxide
Fe2O3 2 x 55.8 + 3 x 16 = 159.6
Find the equality for the
compounds below
• 1.00 mole CuCO3 = 123.5g
• 5.0 grams CuCO3
• 0.0404 moles CuCO3
How to do the worksheet
More Worksheet
Quiz
• 1. How many grams in a mole of sodium?
• 2. How many grams in a mole of sodium
chloride?
• 3. How many grams in a mole of oxygen?
• 4. If you have 56 grams of carbon
monoxide you have ______ moles
• 5. how many atoms are in one mole?
Quiz
• 6. How many moles of oxygen atoms are
in one mole of oxygen molecules?
• 7. How many moles of hydrogen atoms
are in two moles of C12H22O11 molecules?
• 8. 2.5 moles of K2O = _____ grams.
• 9. How many dozen eggs are in 2.4 x102
eggs?
• 10. 3.01 x 1023 = _______ moles