Mr. MOLE!
Mole
 Mole - The measurement of Matter.
 We live in a quantitative world.
 With various commodities you may keep track of
items via “pair”or “dozen”, etc.. Or by mass
“grams” , “kilograms”, or “pounds”. With liquids
such as milk you may measure and purchase via
volume: quart, gallon, pint.
MOLE
 In chemistry, the measuring unit MOLE is used.
 Mole of substance can relate to:
 No. of atoms, molecules, or formula units.
 Mass of compound
 Volume
Avogadro’s Number
 The mole represents 6.02 x 1023 particles.

Particles can be atoms, molecules, or formula
units.
 Atom He – monoatomic Fe – metal atom
 Molecules H2, N2, O2 (diatomic) or H2O,SO2
 Formula Units (Ionic Compounds)
CaCl2
One gram formula mass (gfm) is shown for each of
three ionic compounds.
Each of these quanitities contains 6.022 x 1023 formula
units.
Which of these compounds contains the greatest
number of atoms?
How many atoms in a mole of a
compound???
O
Determine from formula.
(e.g.) Carbon Dioxide
C
O
CO2
Contains 3 atoms (1 carbon & 2 oxygens)
Thus 1 mole of CO2 contains
6.02 x 1023 atoms of carbon + 2(6.02 x 1023 atoms of oxygen)
= 18 x 1023 atoms of C & H
But how many molecules of CO2 are in one mole of CO2????
How many atoms in 1 mole of CO?
O
C
 6.02 x 1023 atoms of carbon
 6.02 x 1023 atoms of oxygen
 Equals 12.04 x 1023 atoms of carbon & oxygen
 But 6.02 x 1023 molecules of CO
O
Example Problem :
 How many atoms in 2.12 moles of propane (C3H8)?
 3 carbons and 8 hydrogens = 11 atoms in propane
per molecule
2.12 mol C3H8 | 6.02 x 1023 molecules of C3H8 | 11 atoms
|
1 mol C3H8
| 1 Molecule of C3H8
= 1.40 x 1025 atoms
Avogadro’s Number
 6.022 x 1023 atoms = 1 mole of atoms
 Atoms if just an element.
 Molecules if more than one element together.
 Mole Map: On the wall…
6.022 x
23
10
Mole
 A mole is a measure in chemistry like a dozen is in
baking. It is a way that we can compare the same
number of “things”.
 One mole of anything is equal to Avogadro’s number,
6.022 x 1023 atoms, or 6.022 x 1023 molecules.
 1 mole Na = 6.022 x 1023 atoms = 22.990 g
 1 mole NaCl = 6.022 x 1023 molecules = 53.238 g
 1 mole F2 = 6.022 x 1023 molecules = 37.997 g
Using Avogadro’s number:
 Example:
 What is the mass of 1 atom of Hydrogen?
1 atom H|
1.00794 g H = 1.674 x 10-24 g H
|6.022 x 1023atoms H
Your turn:
 What is the mass of one atom of nitrogen?
1 atom N |
14.0067 g N = 2.326 x 10-23 g N
|6.022 x 1023atoms
Gram Atomic Mass
 Gram Atomic Mass

- atomic mass expressed in grams.
 Carbon 12.011 amu – Grams Atomic Mass is 12.011
grams
 Hydrogen 1.00794 amu – 1.000794 grams
 The Gram atomic mass of any element contains 1 mol of atoms or
6.02 x 1023 atoms
What is the mass of a mole of the
compound Sulfur Trioxide?
 First need to determine formula of compound.
The formula tells you the number of each element
present. (5 significant figures!)
=
SO3
Formula
Mass of
SO3
+
= S atom + 3 O atoms
+
= 32.056 3(15.999)
= 80.062 g = 1mole
Find the gram molecular mass of glucose…
to 5 significant figures!
 Formula for glucose is C6H12O6





For Carbon
6(12.011g) = 72.066 g
For Hydrogen
12(1.0079g) = 12.0948g
For Oxygen 6(15.999 g) = 95.994 g
180.15 g
Glucose has a mass of 180.15 g/mole
Working with Ionic Compounds
 Formula Units – Lowest Whole Number ratio to 5 sig
figures!
 Find the gram formula mass for Calcium Iodide,
CaI2



Ca
40.1 g 1( 40.078 g)= 40.078 g
I 126.9 g 2(126.9 0g)= 253.80 g
293.90 g
Mole / Mass and
Mole / Volume Relationships
 Gram Atomic Mass

Gram Moles of He, Ar, U?
 Gram Molecular Mass

Gram Moles of CO2, H2, N2, O2 ?