Chemical Quantities:
Chapter 10
I. The Mole &
Molar Conversions
I
II
III
IV
A mole of paperclips
Measure the length of a paper clip to
the nearest 0.1cm.
 If a mole is 6.02x1023 items, how far
will a mole of paper clips, placed end
to end lengthwise, reach into space?

How many light years (ly) would the
paper clips extend into space?
(1 ly = 9.46 x 1015 m).
 How does the distance you calculated
compare with the following
astronomical distances: nearest star
(other than the sun) = 4.3 ly, center of
our galaxy = 30,000 ly, nearest
galaxy = 2 x 106 ly?

A. What is the Mole?

A counting number (like a dozen)

Avogadro’s number (NA)

1 mol = 6.02 x 1023 items (atoms, molecules,
formula units)

1 mol is the SI unit used to measure amount
of a substance
A
large amount!!!!
A. What is the Mole?

1 mole of hockey pucks would
equal the mass of the moon!

1 mole of basketballs would fill a
bag the size of the earth!

1 mole of pennies would cover
the Earth 1/4 mile deep!
B. Molar Mass

Mass of 1 mole of an element or
compound.

Atomic mass tells the...
 atomic mass units per atom (amu)
 grams per mole (g/mol)

Round to 2 decimal places
B. Molar Mass Examples

carbon
12.01 g/mol

aluminum
26.98 g/mol

zinc
65.39 g/mol
B. Molar Mass Examples

water
 H2O
 2(1.01) + 16.00 = 18.02 g/mol

sodium chloride
 NaCl
 22.99 + 35.45 = 58.44 g/mol
B. Molar Mass Examples

sodium bicarbonate
 NaHCO3
 22.99 + 1.01 + 12.01 + 3(16.00)
= 84.01 g/mol

sucrose
 C12H22O11
 12(12.01) + 22(1.01) + 11(16.00)
= 342.34 g/mol
C. Molar Conversions
molar
mass
6.02 x 1023
MASS
NUMBER
MOLES
IN
GRAMS
OF
PARTICLES
(g/mol)
(particles/mol)
C. Mole-Mass Conversions

Your class bought jellybeans in bulk
to sell by the dozen. It’s too much
work to count out each dozen, so you
decide to measure the jellybeans by
mass. You find that 1 dozen
jellybeans equals 35g. What mass of
jellybeans should you measure if a
customer wants 5 dozen jellybeans?
Jellybean Problem
C. Molar Conversion Examples
 How
many moles of carbon are
in 26 g of carbon?
26 g C 1 mol C
12.01 g C
= 2.2 mol C
C. Molar Conversion Examples

You need 3.00 mol of manganese for
a chemical reaction, how can you
measure that amount?
C. Mole-Particles Conversions

You buy 3.5 dozen roses for your
mom, how many roses did you buy?
C. Molar Conversion Examples
 How
many molecules are in
2.50 moles of C12H22O11?
6.02 x 1023
2.50 mol molecules
1 mol
= 1.51 x 1024
molecules
C12H22O11
C. Molar Conversion Examples

Determine the number of atoms in
2.50 mol of Zn.
C. Molar Conversion Examples

Calculate the number of moles that
contain 3.58x1023 formula units of
ZnCl2?
C. Mass-Moles- Particles
Conversions

If 550 grams of jellybeans are unsold
from your class fundraiser, without
counting can you determine how
many jellybeans this is? (remember
you determined that 1 dozen
jellybeans = 35 g)
Jellybean Problem 2
C. Molar Conversion Examples
the mass of 2.1  1024
molecules of NaHCO3.
 Find
2.1 x 1024
molecules
1 mol
84.01 g
6.02 x 1023 1 mol
molecules
= 290 g NaHCO3
C. Molar Conversion Examples

How many atoms are in 0.230 g of
Pb?

What is the mass in grams 1.50x1015
atoms N?
Practice Problems 

How many marbles are in 0.200 mol
of marbles?
Practice Problems 

How many moles of magnesium is
1.25 x 1023 atoms of magnesium?
Practice Problems 

How many atoms are in 2.12 mol of
propane (C3H8)?
Practice Problems 

How many moles are there in 4.65
x1024 molecules of NO2?
D. Mole-Volume Conversions

1 mol of gas = 22.4 L at STP
 STP = standard temperature (0oC)
& pressure (1 atm)
D. Molar Conversion Examples
Determine the volume, in liters, of 0.60
mol SO2 gas at STP.
0.6 mol SO2
22.4L SO2 = 13L SO2
1 mol SO2
D. Molar Conversion Examples

Assuming STP, how many moles are
in 0.880 L He?
3.93 x 10-2 mol He

What is the volume at STP of 3.70
mol N2?
82.9 L N2
D. Molar Conversions
The density of a gaseous compound
containing carbon and oxygen is
1.964 g/L at STP. Determine the
molar mass of the compound.
44.0 g/mol
 What is the density of krypton gas at
STP?
3.74 g/L
