This document discusses the mole, which is a unit used to measure amounts of substances. It defines key terms related to the mole, such as Avogadro's number and molar mass. The mole allows chemists to convert between the number of particles and mass of a substance. The document explains how subscripts in chemical formulas indicate the number of atoms of each element in one molecular formula unit and in one mole of a compound. It provides an example problem calculating the number of oxygen atoms in a given number of moles of aspirin.

1. 1
Chapter 10
Chemical Quantities
10.2
The Mole
Copyright © 2008 by Pearson Education, Inc.
Publishing as Benjamin Cummings

2. Section 10.1
The Mole: A Measurement of
Matter
 OBJECTIVES:
Describe methods of
measuring the amount
of something.

3. Section 10.1
The Mole: A Measurement of
Matter
 OBJECTIVES:
Define Avogadro’s
number as it relates to
a mole of a substance.

4. Section 10.1
The Mole: A Measurement of
Matter
 OBJECTIVES:
Distinguish between
the atomic mass of an
element and its molar
mass.

5. Section 10.1
The Mole: A Measurement of
Matter
 OBJECTIVES:
Describe how the
mass of a mole of a
compound is
calculated.

6. 6
Collection Terms
A collection term states a specific number of items.
• 1 dozen donuts = 12 donuts
• 1 ream of paper = 500 sheets
• 1 case = 24 cans
Copyright © 2008 by Pearson Education, Inc.
Publishing as Benjamin Cummings

7. 7
A mole (mol) is a collection that contains
• The same number of particles as there are
carbon atoms in 12.01 g of carbon.
• 6.022 x 1023 atoms of an element (Avogadro’s
number).
1 mol C = 6.022 x 1023 C atoms
1 mol CO2 = 6.022 x 1023 CO2 molecules
1 mol NaCl = 6.022 x 1023 NaCl formula units
A Mole of Particles

8. 8
Samples of One Mole
Quantities
Table 6.1
Copyright © 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings

9. 9
Using Avogadro’s Number
Avogadro’s number
• Converts moles of a substance to
the number of particles.
• Converts particles of a substance to
moles.
Copyright © 2008 by Pearson Education, Inc.
Publishing as Benjamin Cummings

10. 10
Subscripts and Moles
The subscripts in a formula state
• The relationship of atoms in the formula.
• The moles of each element in 1 mol of
compound.
Glucose
C6H12O6
In 1 molecule: 6 atoms C 12 atoms H 6 atoms O
In 1 mol: 6 mol C 12 mol H 6 mol O

11. 11
Subscripts State Atoms and
Moles
1 mol C9H8O4 = 9 mol C 8 mol H 4 mol O
Copyright © 2008 by Pearson Education, Inc.
Publishing as Benjamin Cummings

12. 12
Learning Check
A. How many moles O are in 0.150 mol aspirin
C9H8O4?
B. How many O atoms are in 0.150 mol aspirin
C9H8O4?

13. 13
Solution
A. How many mol O are in 0.150 mol aspirin C9H8O4?
0.150 mol C9H8O4 x 4 mol O = 0.600 mol O
1 mol C9H8O4
subscript factor
B. How many O atoms are in 0.150 mol aspirin C9H8O4?
0.150 mol C9H8O4 x 4 mol O x 6.022 x 1023 O atoms
1 mol C9H8O4 1 mol O
subscript Avogadro’s
factor Number
= 3.61 x 1023 O atoms

14. 14
Learning Check
How many O atoms are in 0.150 mol aspirin C9H8O4?

15. 15
Solution
How many O atoms are in 0.150 mol aspirin C9H8O4?
0.150 mol C9H8O4 x 4 mol O x 6.022 x 1023 O atoms
1 mol C9H8O4 1 mol O
subscript Avogadro’s
factor number
= 3.61 x 1023 O atoms