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.
2. Section 10.1
The Mole: A Measurement of
Matter
๏ข OBJECTIVES:
๏ฌDescribe methods of
measuring the amount
of something.
3. Section 10.1
The Mole: A Measurement of
Matter
๏ข OBJECTIVES:
๏ฌDefine Avogadroโs
number as it relates to
a mole of a substance.
4. Section 10.1
The Mole: A Measurement of
Matter
๏ข OBJECTIVES:
๏ฌDistinguish between
the atomic mass of an
element and its molar
mass.
5. Section 10.1
The Mole: A Measurement of
Matter
๏ข OBJECTIVES:
๏ฌDescribe how the
mass of a mole of a
compound is
calculated.
6. 6
Collection Terms
A collection term states a specific number of items.
โข 1 dozen donuts = 12 donuts
โข 1 ream of paper = 500 sheets
โข 1 case = 24 cans
Copyright ยฉ 2008 by Pearson Education, Inc.
Publishing as Benjamin Cummings
7. 7
A mole (mol) is a collection that contains
โข The same number of particles as there are
carbon atoms in 12.01 g of carbon.
โข 6.022 x 1023 atoms of an element (Avogadroโs
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 ยฉ 2008 by Pearson Education, Inc. Publishing as Benjamin Cummings
9. 9
Using Avogadroโs Number
Avogadroโs number
โข Converts moles of a substance to
the number of particles.
โข Converts particles of a substance to
moles.
Copyright ยฉ 2008 by Pearson Education, Inc.
Publishing as Benjamin Cummings
10. 10
Subscripts and Moles
The subscripts in a formula state
โข The relationship of atoms in the formula.
โข 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 ยฉ 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 Avogadroโs
factor Number
= 3.61 x 1023 O atoms
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 Avogadroโs
factor number
= 3.61 x 1023 O atoms