THURSDAY, SEPTEMBER 13, 2012
*Pick up computer, log-in and go to podcast page.
*Have out the quiz sheet from yesterday.
*SEE ME immediately with the 3.1/3.2 worksheet if you had not
turned in previously.
CW: Check homework problems and quiz sheet
CW: Computer Review Games & Chemthink.com
CW/HW: Study Guide Questions and TEST due tomorrow!
Chapter 3 Review sheet handout & Avogadro’s Number MiniLab may do as well...
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Lesson Starter
• Imagine that your semester grade depends 60% on
exam scores and 40% on laboratory explorations.
• Your exam scores would count more heavily toward
your final grade.
• In this section, you will learn that the atomic mass of
an element is a weighted average of the masses of
the naturally occurring isotopes of that element.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Opener #2 - Tuesday, January 29, 2013
1. What does the Law of Conservation of Mass state?
2. How does NaCl (table salt) follow the Law of Definite
Proportions?
3. How does the diagram depict the Law of Multiple
Proportions?
CW: Notes 3.3 together...
CW: M&Mium isotope lab
CW: Chemthink.com if time
permits
HW: Study Guide due FRI
BUT TEST is on FRIDAY
for ch. 3 only.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Opener #3 - Tuesday, Sept. 11, 2012
1. What does the Law of Conservation of Mass state?
The mass of the reactants is the same as the total mass of
the products. Matter cannot be created or destroyed.
2. How does NaCl (table salt) follow the Law of Definite
Proportions? It is always made up of same ratio of
element which is 39.34% Na and 60.66% Cl.
3. How does the diagram depict the Law of Multiple
Proportions?
If amount of H remains the same
but if twice atoms of Oxygen &
H still has same amount, then
oxygen mass must also double.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Objectives
• Explain what isotopes are.
• Define atomic number and mass number, and
describe how they apply to isotopes.
• Given the identity of a nuclide, determine its number
of protons, neutrons, and electrons.
• Define mole, Avogadro’s number, and molar mass,
and state how all three are related.
• Solve problems involving mass in grams, amount
in moles, and number of atoms of an element.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
3.3
Distinguishing Among Atoms
Connecting to Your World
Just as apples come in
different varieties, a
chemical element can
come in different
“varieties” called isotopes.
Slide
of 52
6
© Copyright Pearson Prentice Hall
End Show
3.3
Distinguishing Among Atoms
>
Atomic Number
Atomic Number
What makes one element different from
another?
Slide
of 52
7
© Copyright Pearson Prentice Hall
End Show
Chapter 3
Section 3 Counting Atoms
Atomic Number
• Atoms of different elements have different numbers of
protons.
• Atoms of the same element all have the same number
of protons.
• The atomic number (Z) of an element is the number
of protons of each atom of that element.
• The atomic number identifies the element.
• Because all atoms are neutral, the number of protons
equals the number of electrons.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
3.3
Distinguishing Among Atoms
>
Atomic Number
Elements are different because they
contain different numbers of protons.
The atomic number of an element is the
number of protons in the nucleus of an
atom of that element.
Slide
of 52
9
© Copyright Pearson Prentice Hall
End Show
3.3
Distinguishing Among Atoms
>
Atomic Number
Slide
of 52
10
© Copyright Pearson Prentice Hall
End Show
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
Atomic Number
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
Practice Problems
for Conceptual Problem 4.15
Click here for Problem 4.15
to check answers
Problem Solving 4.15 Solve Problem
15 with the help of an interactive
guided tutorial.
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
Chapter 3
Visual Concepts
Atomic Number
⬅atomic number
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
3.3
Distinguishing Among Atoms
>
Mass Number
Mass Number
How do you find the number of neutrons
in an atom?
Slide
of 52
16
© Copyright Pearson Prentice Hall
End Show
3.3
Distinguishing Among Atoms
>
Mass Number
The total number of protons and neutrons in an
atom is called the mass number.
The number of neutrons in an atom is
the difference between the mass
number and atomic number.
Slide
of 52
17
© Copyright Pearson Prentice Hall
End Show
Chapter 3
Visual Concepts
Average Mass Number, atomic weight or
atomic mass
⬅average mass number
or average atomic weight
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
SAMPLE PROBLEM 4.1
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
SAMPLE PROBLEM 4.1
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
SAMPLE PROBLEM 4.1
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
SAMPLE PROBLEM 4.1
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
Practice Problems
for Sample Problem 4.1
Click here to check answers.
Problem Solving 4.17 Solve Problem
17 with the help of an interactive
guided tutorial.
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
Chapter 3
Visual Concepts
Isotopes and Nuclides
QuickTime™ and a
Sorenson Video 3 decompressor
are needed to see this picture.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Isotopes
• Isotopes are atoms of the same element that have
different masses.
• The isotopes of a particular element all have the same
number of protons and electrons but different numbers
of neutrons.
• Most of the elements consist of mixtures of isotopes.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
3.3
Distinguishing Among Atoms
>
Isotopes
Despite these differences, isotopes are
chemically alike because they have identical
numbers of protons and electrons.
Slide
of 52
26
© Copyright Pearson Prentice Hall
End Show
Chapter 3
Section 3 Counting Atoms
Mass Number
• The mass number is the total number of protons
and neutrons that make up the nucleus of an
isotope.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Designating Isotopes
• Hyphen notation: The mass number is written with a
hyphen after the name of the element.
uranium-235
U-235
• Nuclear symbol: The superscript indicates the mass
number and the subscript indicates the atomic
mass number--➡
number.
atomic number➡
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Designating Isotopes, continued
• The number of neutrons is found by subtracting the
atomic number from the mass number.
mass number  atomic number = number of neutrons
235 (protons + neutrons)  92 protons = 143 neutrons
• Nuclide is a general term for a specific isotope of an
element.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Hydrogen Isotopes
• There are 3 special names for hydrogen isotopes.
• All Hydrogen atoms have 1 proton and 1 electron but vary in
the number of neutrons as all isotopes do.
• Protium, H-1, is the most common type, 99.9885%,
nucleus consists of 1 proton and no neutrons.
• Deuterium, H-2, accounts for 0.0115% of Earth’s hydrogen
and has 1 proton and 1 neutron.
• Tritium, H-3, accounts for 0.0115% of Earth’s hydrogen,
nucleus consists of 1 proton and 2 neutrons.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Designating Isotopes, continued
Sample Problem A
How many protons, electrons, and neutrons are there in
an atom of chlorine-37?
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Designating Isotopes, continued
Sample Problem A Solution
Given: name and mass number of chlorine-37
Unknown: numbers of protons, electrons, and
neutrons
Solution:
atomic number = number of protons = number of
electrons
mass number = number of neutrons + number of
protons
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Designating Isotopes, continued
Sample Problem A Solution, continued
mass number of chlorine-37  atomic number of
chlorine = number of neutrons in chlorine-37
mass number  atomic number = 37 (protons plus
neutrons)  17 protons = 20 neutrons
An atom of chlorine-37 is made up of 17 electrons, 17
protons, and 20 neutrons.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Practice Problems
for Conceptual Problem 4.20
Click here to check answers 4.20
Problem Solving 4.20
Solve Problem 20 with the help
of an interactive guided tutorial.
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
Chapter 3
Section 3 Counting Atoms
Relative Atomic Masses
• The standard used by scientists to compare units of atomic
mass is the carbon-12 atom, which has been arbitrarily
assigned a mass of exactly 12 atomic mass units, or 12
amu.
• One atomic mass unit, or 1 amu, is exactly 1/12 the mass
of a carbon-12 atom.
• The atomic mass of any atom is determined by comparing it
with the mass of the carbon-12 atom.
• Isotopes have different masses, but have similar chemical
behavior. Protons & neutrons masses are close to 1 amu.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
COMPOSITION OF THE ATOM CONCEPT MAP
ACTIVITY
CLICK HERE FOR CONCEPT MAP ACTIVITY ON ATOM
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
M&M Isotope Mini-Lab
Stop here and do this activity lab.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
3.3
Distinguishing Among Atoms
>
Atomic Mass
Atomic Mass
How do you calculate the atomic mass
of an element?
Slide
of 52
38
© Copyright Pearson Prentice Hall
End Show
Chapter 3
Section 3 Counting Atoms
Average Atomic Masses of Elements
• Average atomic mass is the weighted average of the
atomic masses of the naturally occurring isotopes of
an element.
Calculating Average Atomic Mass
• The average atomic mass of an element depends on
both the mass and the relative abundance of each of
the element’s isotopes.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Visual Concepts
Average Atomic Mass
Click below to watch the Visual Concept.
http://my.hrw.com/sh/hc6_00303
Visual Concept
6809x/student/ch03/sec03/vc03/h
c603_03_v03fs.htm
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Average Atomic Masses of Elements,
continued
Calculating Average Atomic Mass, continued
• Copper consists of 69.15% copper-63, which has an
atomic mass of 62.929 601 amu, and 30.85% copper65, which has an atomic mass of 64.927 794 amu.
• The average atomic mass of copper can be calculated
by multiplying the atomic mass of each isotope by its
relative abundance (expressed in decimal form) and
adding the results.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Average Atomic Masses of Elements,
continued
Calculating Average Atomic Mass, continued
• (0.6915  62.929 601 amu) + (0.3085 
64.927 794 amu) = 63.55 amu
• The calculated average atomic mass of naturally
occurring copper is 63.55 amu.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
3.3
Distinguishing Among Atoms
>
Atomic Mass
For example, carbon has two stable isotopes:
• Carbon-12, which has a natural abundance of
98.89%, and
• Carbon-13, which has a natural abundance of
1.11%.
Slide
of 52
46
© Copyright Pearson Prentice Hall
End Show
START HERE WEDNESDAY
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
Opener #4 - Wednesday, Sept. 12, 2012
1. Calculate the weighted average atomic mass if
CW: Notes 3.3B + problems together...
CW: How many room of M&M’s is Avogadro’s # mini-lab?
CW: QUIZ & Chemthink.com
Last chance to get points for ch. 3.1-3.2 w/sheet IN BOX.
HW: Study Guide due FRI AND TEST is on FRIDAY
for ch. 3 only.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
SAMPLE PROBLEM 4.2
OPENER ANSWER WORKED OUT...
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
SAMPLE PROBLEM 4.2
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
3.3
Distinguishing Among Atoms
>
Atomic Mass
To calculate the weighted average
atomic mass of an element, multiply the
mass of each isotope by its natural
abundance, expressed as a decimal, and
then add the products.
Slide
of 52
51
© Copyright Pearson Prentice Hall
End Show
SAMPLE PROBLEM 4.2
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
SAMPLE PROBLEM 4.2
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
Practice Problems for Conceptual Problem 4.3
for Conceptual Problem 4.3
Problem Solving 4.21 Solve
Problem 21 with the help of
an interactive guided tutorial.
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
Practice Problems for Conceptual Problem 4.3
for Conceptual Problem 4.3
ANSWER: Since 10.81 is closer to 11 than to 10, B-11 would occur in nature at a
higher percentage than that of B-10. If these were the only 2 isotopes of Boron, you
could determine the exact percentages.
Problem Solving 4.21 Solve
Problem 21 with the help of
an interactive guided tutorial.
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
Practice Problems
for Sample Problem 4.2
Click here to check answer
Problem Solving 4.24 Solve
Problem 24 with the help of an
interactive guided tutorial.
Slide
of 52
© Copyright Pearson Prentice Hall
End Show
10.1
The Mole: A Measurement of Matter
You could measure the amount
of sand in a sand sculpture by
counting each grain of sand,
but it would be much easier to
weigh the sand. You’ll discover
how chemists measure the
amount of a substance using a
unit called a mole, which
relates the number of particles
to the mass.
Slide
of 43
57
© Copyright Pearson Prentice Hall
End Show
10.1
The Mole: A Measurement of>
Matter
Measuring Matter
Measuring Matter
What are three methods for measuring
the amount of something?
Slide
of 43
58
© Copyright Pearson Prentice Hall
End Show
10.1
The Mole: A Measurement of>
Matter
Measuring Matter
You often measure the amount of
something by one of three different
methods—by count, by mass, and by
volume.
Slide
of 43
59
© Copyright Pearson Prentice Hall
End Show
Chapter 3
Visual Concepts
The Mole
Click below to watch the Visual Concept.
http://my.hrw.com/sh/hc6_00303
Visual Concept
6809x/student/ch03/sec03/vc04/h
c603_03_v04fs.htm
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Relating Mass to Numbers of Atoms
The Mole
• The mole is the SI unit for amount of substance.
• A mole (abbreviated mol) is the amount of a
substance that contains as many particles as there
are atoms in exactly 12 g of carbon-12.
Avogadro’s Number
• Avogadro’s number—6.022 1415  1023—is the
number of particles in exactly one mole of a pure
substance.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Visual Concepts
Avogadro’s Number - Don’t show yet until
after mini-lab
Click below to watch the Visual Concept.
http://my.hrw.com/sh/hc6_003036809x/st
Visual Concept
udent/ch03/sec03/vc05/hc603_03_v05fs.
htm
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
10.1
The Mole: A Measurement of>
Matter
What is a Mole?
A mole of any substance contains
Avogadro’s number or 6.02  1023
representative particles.
The term representative particle refers to
the species present in a substance: usually
atoms, molecules, or formula units.
Slide
of 43
63
© Copyright Pearson Prentice Hall
End Show
10.1
The Mole: A Measurement of>
Matter
What is a Mole?
Converting Number of Particles to Moles
One mole (mol) of a substance is 6.02  1023
representative particles of that substance and is
the SI unit for measuring the amount of a
substance.
The number of representative particles in a
mole, 6.02  1023, is called Avogadro’s number.
Slide
of 43
64
© Copyright Pearson Prentice Hall
End Show
10.1
The Mole: A Measurement of>
Matter
What is a Mole?
*1 mole of any element or compound is always ___________
to a mole of another compound in the amount of substance
Slide
but will have different masses.
of 43
65
© Copyright Pearson Prentice Hall
End Show
10.1
The Mole: A Measurement of>
Matter
The Mass of a Mole of an
Element
The Mass of a Mole of an Element
How is the atomic mass of an element
related to the molar mass of an
element?
Slide
of 43
66
© Copyright Pearson Prentice Hall
End Show
10.1
The Mole: A Measurement of>
Matter
The Mass of a Mole of an
Element
The atomic mass of an element
expressed in grams is the mass of a mole
of the element.
The mass of a mole of an element is its
molar mass.
Slide
of 43
67
© Copyright Pearson Prentice Hall
End Show
10.1
The Mole: A Measurement of>
Matter
The Mass of a Mole of an
Element
One molar mass of carbon, sulfur, mercury, and
iron are shown.
Slide
of 43
68
© Copyright Pearson Prentice Hall
End Show
Chapter 3 Section 3 Counting Atoms
Relating Mass to Numbers of Atoms,
continued
Molar Mass
• The mass of one mole of a pure substance is called
the molar mass of that substance.
• Molar mass is usually written in units of g/mol.
• The molar mass of an element is numerically equal to
the atomic mass of the element in atomic mass units.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Relating Mass to Numbers of Atoms,
continued
Gram/Mole Conversions
• Chemists use molar mass as a conversion factor in
chemical calculations.
• For example, the molar mass of helium is 4.00 g
He/mol He.
• To find how many grams of helium there are in two
moles of helium, multiply by the molar mass.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
10.1
The Mole: A Measurement of>
Matter
The Mass of a Mole of a
Compound
The Mass of a Mole of a Compound
How is the mass of a mole of a
compound calculated?
Slide
of 43
71
© Copyright Pearson Prentice Hall
End Show
10.1
The Mole: A Measurement of>
Matter
The Mass of a Mole of a
Compound
To calculate the molar mass of a
compound, find the number of grams of
each element in one mole of the
compound. Then add the masses of the
elements in the compound.
Slide
of 43
72
© Copyright Pearson Prentice Hall
End Show
10.1
The Mole: A Measurement of>
Matter
The Mass of a Mole of a
Compound
Substitute the unit grams for atomic mass units.
Thus 1 mol of SO3 has a mass of 80.1 g.
Slide
of 43
73
© Copyright Pearson Prentice Hall
End Show
SAMPLE PROBLEM 10.4
Slide
of 43
© Copyright Pearson Prentice Hall
End Show
SAMPLE PROBLEM 10.4
Slide
of 43
© Copyright Pearson Prentice Hall
End Show
SAMPLE PROBLEM 10.4
Slide
of 43
© Copyright Pearson Prentice Hall
End Show
SAMPLE PROBLEM 10.4
Slide
of 43
© Copyright Pearson Prentice Hall
End Show
Practice Problems
for Sample Problem 10.4
Problem Solving 10.7 Solve
Problem 7 with the help of an
interactive guided tutorial.
Slide
of 43
© Copyright Pearson Prentice Hall
End Show
GRAM-MOLE CONVERSIONS PROBLEM
ACTIVITY - see online book - skip for now.
CLICK HERE FOR GRAM/MOLE PROBLEM ACTIVITY
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Relating Mass to Numbers of Atoms,
continued
Conversions with Avogadro’s Number
• Avogadro’s number can be used to find the number
of atoms of an element from the amount in moles or
to find the amount of an element in moles from the
number of atoms.
• In these calculations, Avogadro’s number is
expressed in units of atoms per mole.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
AVOGADRO’S NUMBER CONVERSIONS
PROBLEM ACTIVITY
CLICK HERE FOR AVOGADRO'S NUMBER PROBLEM
ACTIVITY
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Solving Mole Problems
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Determining the Mass from the Amount in
Moles
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Relating Mass to Numbers of Atoms,
continued
Sample Problem B
What is the mass in grams of 3.50 mol of the
element copper, Cu?
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Relating Mass to Numbers of Atoms,
continued
Sample Problem B Solution
Given: 3.50 mol Cu
Unknown: mass of Cu in grams
Solution: the mass of an element in grams can be
calculated by multiplying the amount of the element
in moles by the element’s molar mass.
grams Cu
moles Cu 
= grams Cu
moles Cu
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Relating Mass to Numbers of Atoms,
continued
Sample Problem B Solution, continued
The molar mass of copper from the periodic table is
rounded to 63.55 g/mol.
3.50 mol Cu 
63.55 g Cu
= 222 g Cu
1 mol Cu
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Relating Mass to Numbers of Atoms,
continued
Sample Problem C
A chemist produced 11.9 g of aluminum, Al. How
many moles of aluminum were produced?
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Relating Mass to Numbers of Atoms,
continued
Sample Problem C Solution
Given: 11.9 g Al
Unknown: amount of Al in moles
Solution:
The molar mass of aluminum from the periodic table
is rounded to 26.98 g/mol.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Relating Mass to Numbers of Atoms,
continued
Sample Problem D
How many moles of silver, Ag, are in 3.01  1023 atoms
of silver?
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Relating Mass to Numbers of Atoms,
continued
Sample Problem D Solution
Given: 3.01  1023 atoms of Ag
Unknown: amount of Ag in moles
Solution:
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Relating Mass to Numbers of Atoms,
continued
Sample Problem E
What is the mass in grams of 1.20  108 atoms of
copper, Cu?
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 3
Section 3 Counting Atoms
Relating Mass to Numbers of Atoms, continued
Sample Problem E Solution
Given: 1.20  108 atoms of Cu
Unknown: mass of Cu in grams
Solution:
The molar mass of copper from the periodic table is
rounded to 63.55 g/mol.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
10.1 Section Quiz.
Assess students’ understanding of
the concepts in Section
10.1.
Continue to:
-or-
Launch:
Section Quiz
Slide
of 43
© Copyright Pearson Prentice Hall
End Show
10.1 Section Quiz.
1. Three common ways of measuring the amount
of something are by count, by mass, and
a. by temperature.
b. by volume.
c. by area.
d. by density.
Slide
of 43
© Copyright Pearson Prentice Hall
End Show
10.1 Section Quiz.
2. A mole of hydrogen gas, H2(g), contains 6.02
x 1023
a. molecules.
b. atoms.
c. amu.
d. grams.
Slide
of 43
© Copyright Pearson Prentice Hall
End Show
10.1 Section Quiz.
3. The atomic mass of fluorine is 19.0 amu, so
the molar mass is
a. 19.0 amu.
b. 19.0 g.
c. 6.02 x 1023 amu.
d. 6.02 x 1023 g.
Slide
of 43
© Copyright Pearson Prentice Hall
End Show
10.1 Section Quiz.
4. Calculate the molar mass of ammonium nitrate.
a. 45.02 g
b. 80.05 g
c. 60.06 g
d. 48.05 g
Slide
of 43
© Copyright Pearson Prentice Hall
End Show
3.3 Section Quiz
Assess students’ understanding of
the concepts in Section
4.3.
Continue to:
-or-
Launch:
Section Quiz
Slide
of 18
© Copyright Pearson Prentice Hall
End Show
3.3 Section Quiz
1. Isotopes of an element have
a. the same mass number.
b. different atomic numbers.
c. the same number of protons but different
numbers of neutrons.
d. the same number of protons but different
numbers of electrons.
Slide
of 18
© Copyright Pearson Prentice Hall
End Show
3.3 Section Quiz
2. How many neutrons are in sulfur-33?
a. 16 neutrons
b. 33 neutrons
c. 17 neutrons
d. 32.06 neutrons
Slide
of 18
© Copyright Pearson Prentice Hall
End Show
3.3 Section Quiz
3. If sulfur contained 90.0% sulfur-32 and 10.0%
sulfur-34, its atomic mass would be
a. 32.2 amu.
b. 32.4 amu.
c. 33.0 amu.
d. 35.4 amu.
Slide
of 18
© Copyright Pearson Prentice Hall
End Show
Distinguishing Among Atoms
>
Concept Map
Slide
of 52
102
© Copyright Pearson Prentice Hall
End Show
online SELF-CHECK QUIZ FOR SECT. 1.3
TAKE THE FOLLOWING QUIZ. Record your
answers. Ask questions for any answer that
you do not understand.
CLICK BELOW TO TAKE THE QUIZ. YOU MUST
BE IN THE PLAY MODE OF THE SLIDE
SHOW.
QUIZ SECTION 3.3 MODERN CHEMISTRY HOLT
RECORD THE 10 ANSWERS IN NOTES.
Slide
of 27
© Copyright Pearson Prentice Hall
End Show
VIDEOS FOR ADDITIONAL INSTRUCTION
Additional Videos for Section 3.3 Counting Atoms (5 videoclips)
•Atomic Number - Isotopes (4:47)
•Atomic Mass (4:19)
•Chemistry Mole (5:16)
•Molar Mass (5:32)
•Avogadro's Principle (4:01)
Slide
of 27
© Copyright Pearson Prentice Hall
End Show
SCI LINKS FOR CHAPTER
Additional Student SCI LINKS for CHAPTER 3
The NSTA-sponsored SciLinks Web site contains links to accurate and upto-date science
information on the Internet. Just click on the button below to go to the
SciLinks site at
www.scilinks.org and log in. Then, type in the SciLinks code for the topic
you want to
research. The following is a list of the SciLinks codes for this chapter.
Chapter 3: Atoms: The Building Blocks of Matter
Topic: Atomic Theory
SciLinks code: HC60120
© Copyright Pearson Prentice Hall
Slide
of 27
End Show
End of Chapter 3 Show
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.