Georgia Science Grade 8

258 Pages·2007·2.65 MB·English

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Consultant
Douglas Fisher, Ph.D.

Georgia Science
Grade 8

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Copyright © by the McGraw-Hill Companies, Inc. All rights reserved. Permission is granted to reproduce the material
contained herein on the condition that such material be reproduced only for classroom use; be provided to students,
teachers, and families without charge; and be used solely in conjunction with Georgia Science, Grade 8. Any other
reproduction, for use or sale, is prohibited without prior written permission of the publisher.

Send all inquiries to:
Glencoe/McGraw-Hill
8787 Orion Place
Columbus, Ohio 43240-4027

ISBN: 978-0-07-879240-3
MHID: 0-07-879240-1

Printed in the United States of America

1 2 3 4 5 6 7 8 9
047
12 11 10 09 08 07

About the Consultant

Douglas Fisher, Ph.D., is a Professor in the Department of Teacher
Education at San Diego State University. He is the recipient of an
International Reading Association Celebrate Literacy Award as well
as a Christa McAuliffe award for Excellence in Teacher Education. He
has published numerous articles on reading and literacy, differentiated
instruction, and curriculum design as well as books, such as Improving
Adolescent Literacy: Strategies at Work and Responsive Curriculum Design
in Secondary Schools: Meeting the Diverse Needs of Students. He has taught
a variety of courses in SDSU’s teacher-credentialing program as well as
graduate-level courses on English language development and literacy.
He also has taught classes in English, writing, and literacy development
to secondary school students.

Georgia Science, Grade 8
iii

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Note-Taking Tips ........................................ v

Using Your Science Notebook ............... vi

Chapter 1 The Nature of Science
Chapter Preview ....................................... 1
1-1............................................................... 2
1-2............................................................... 5
1-3............................................................... 8
1-4............................................................. 11
Wrap-Up ................................................. 14

Chapter 2 Measurement
Chapter Preview..................................... 15
2-1............................................................. 16
2-2............................................................. 19
2-3............................................................. 22
Wrap-Up ................................................. 26

Chapter 3 Atoms, Elements, and
the Periodic Table
Chapter Preview..................................... 27
3-1............................................................. 28
3-2............................................................. 31
3-3............................................................. 34
Wrap-Up ................................................. 38

Chapter 4 States of Matter
Chapter Preview..................................... 39
4-1............................................................. 40
4-2............................................................. 43
4-3............................................................. 46
Wrap-Up ................................................. 50

Chapter 5 Matter—Properties
and Changes
Chapter Preview..................................... 51
5-1............................................................. 52
5-2............................................................. 55
5-3............................................................. 58
Wrap-Up ................................................. 62

Chapter 6 Atomic Structure and
Chemical Bonds
Chapter Preview..................................... 63
6-1............................................................. 64
6-2............................................................. 67
Wrap-Up ................................................. 70

Chapter 7 Chemical Reactions
Chapter Preview..................................... 71
7-1............................................................. 72
7-2............................................................. 75
Wrap-Up ................................................. 78

Chapter 8 Substances, Mixtures,
and Solubility
Chapter Preview..................................... 79
8-1............................................................. 80
8-2............................................................. 83
8-3............................................................. 86
Wrap-Up ................................................. 90

Chapter 9 Carbon Chemistry
Chapter Preview..................................... 91
9-1............................................................. 92
9-2............................................................. 95
9-3............................................................. 98
Wrap-Up ............................................... 102

Chapter 10 Motion and Momentum
Chapter Preview................................... 103
10-1 ........................................................ 104
10-2 ........................................................ 107
10-3 ........................................................ 110
Wrap-Up ............................................... 114

Chapter 11 Force and Newton’s Laws
Chapter Preview................................... 115
11-1 ........................................................ 116
11-2 ........................................................ 119
11-3 ........................................................ 122
Wrap-Up ............................................... 126

iv
Georgia Science, Grade 8

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Chapter 12 Forces and Fluids
Chapter Preview................................... 127
12-1 ........................................................ 128
12-2 ........................................................ 131
12-3 ........................................................ 134
Wrap-Up ............................................... 138

Chapter 13 Energy and Energy
Resources
Chapter Preview................................... 139
13-1 ........................................................ 140
13-2 ........................................................ 143
13-3 ........................................................ 146
Wrap-Up ............................................... 150

Chapter 14 Work and Simple Machines
Chapter Preview................................... 151
14-1 ........................................................ 152
14-2 ........................................................ 155
14-3 ........................................................ 158
Wrap-Up ............................................... 162

Chapter 15 Thermal Energy
Chapter Preview................................... 163
15-1 ........................................................ 164
15-2 ........................................................ 167
15-3 ........................................................ 170
Wrap-Up ............................................... 174

Chapter 16 Waves
Chapter Preview................................... 175
16-1 ........................................................ 176
16-2 ........................................................ 179
16-3 ........................................................ 182
Wrap-Up ............................................... 186

Chapter 17 Sound
Chapter Preview................................... 187
17-1 ........................................................ 188
17-2 ........................................................ 191
Wrap-Up ............................................... 194

Chapter 18 Electromagnetic Waves
Chapter Preview................................... 195
18-1 ........................................................ 196
18-2 ........................................................ 199
18-3 ........................................................ 202
Wrap-Up ............................................... 206

Chapter 19 Light, Mirrors, and Lenses
Chapter Preview................................... 207
19-1 ........................................................ 208
19-2 ........................................................ 211
19-3 ........................................................ 214
19-4 ........................................................ 217
Wrap-Up ............................................... 220

Chapter 20 Electricity
Chapter Preview................................... 221
20-1 ........................................................ 222
20-2 ........................................................ 225
20-3 ........................................................ 228
Wrap-Up ............................................... 232

Chapter 21 Magnetism
Chapter Preview................................... 233
21-1 ........................................................ 234
21-2 ........................................................ 237
Wrap-Up ............................................... 240

Chapter 22 Electronics and Computers
Chapter Preview................................... 241
22-1 ........................................................ 242
22-2 ........................................................ 245
Wrap-Up ............................................... 248

Academic Vocabulary ............................ 249

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Georgia Science, Grade 8
v

Your notes are a reminder of what you learned in class. Taking good
notes can help you succeed in science. These tips will help you take
better notes.

• Be an active listener. Listen for important concepts. Pay attention
to words, examples, and/or diagrams your teacher emphasizes.

• Write your notes as clearly and concisely as possible. The following
symbols and abbreviations may be helpful in your note-taking.

• Use a symbol such as a star (★) or an asterisk (*) to emphasis
important concepts. Place a question mark (?) next to anything that
you do not understand.

• Ask questions and participate in class discussion.

• Draw and label pictures or diagrams to help clarify a concept.

Word or
Symbol or

Phrase
Abbreviation

for example
e.g.

such as
i.e.

with
w/

without
w/o

Word or
Symbol or

Phrase
Abbreviation

and
+

approximately
�

therefore
�

versus
vs

Note-Taking Tips

Note-Taking Don’ts

• Don’t write every word. Concentrate on the main ideas and concepts.

• Don’t use someone else’s notes—they may not make sense.

• Don’t doodle. It distracts you from listening actively.

• Don’t lose focus or you will become lost in your note-taking.

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

vi
Georgia Science, Grade 8

Using Your Science Notebook

Academic Vocabulary

achieve: to gain, accomplish, attain, reach

category: group or class of things

chart: a sheet that gives information about
something in the form of a diagram,
graph, or table

chemical: having to do with or made by
chemistry

compound: to make by combining parts or
elements

conduct: to carry or transmit

confine: hold in one place, restrict

constant: not changing; continuing

convert: to change from one form or use
to another

cycle: a series of events or actions that
repeat regularly

definite: having exact limits; precise and
clear in meaning

device: tool or instrument designed for
a particular purpose

displace: to take the place of or remove
from the usual or proper place

display: to reveal or exhibit

domain: region with the same physical
feature

enable: to make able; to give means or
power to

encounter: to meet or experience

energy: ability to cause movement
or change

enormous: very large

evaluate: to determine the worth of

expand: to get bigger

formula: a symbolic representation of
something

image: visual impression of something
produced by reflection from a mirror
or refraction from a lens

incidence: the striking of a line or a ray
of light on a surface

input: what is put in; the amount of money,
material, or effort put into a project or
process; investment

internal: having to do with the inside

item: object or thing

label: printed material that is fastened
to something to provide information
about it

medium: substance through which a force
or effect is transmitted

occupy: to take up time or space

occur: to take place

output: useful power delivered by a circuit
or device

overall: including everything; total

overlap: one thing extends over another

parallel: being the same distance apart
at all places

percent: in, to, or for every hundred

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Introduction to Physical Science
249

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

The Nature of Science

Before You
Y
Read

Before you read the chapter, respond to these statements.

1. Write
W
an A if you agree with the statement.

2. Write
W
a D if you disagree with the statement.

Name
Date

• An important part of science is testing, or

experimenting.

• Technol
T
ogy is useful only in the situation for

which it was designed.

• People began studying weather in the 1800s.

• Science can answer all of the questions that

can be asked.

Before You
The Nature of Science
Read

The
T
Nature of Science
1

Construct the Foldab
d
le as directed at t
t he
t
beginning of this chapter.

How do you think scientists could learn more about a clump
l
of stone that could be

a small dinosaur heart?

Student responses will vary. Accept responses that discuss some reasonable

experiment.

Complete the following paragraph by filling in the missing terms
from the word bank.

Science is
by what it can
.

For a question or problem to be studied through
,

there must be variables that can be
, measured,

and
. Questions that deal with

or belief systems cannot be answered by science. Ethics is a system

of understanding what is
or
.

Contrast ethical behavior in science with scientific fraud. Create
a table that lists three specific behaviors that are examples of each
type of behavior. Accept all reasonable responses.

bad
good

ethics
tested

observed

scientific methods

explain
limited

• bad
• ethics
• explain

• good
• limited
• observed

• scientific methods
• tested

Section 2 Scientific Enterprise (continued)

Limits of Science

I found this information
on page
.

SE, p. 20
RE, p. 10

Doing Science
Right

I found this information
on page
.

SE, pp. 20–22
RE, pp. 10–12

Name
Date

The Nature of Science
7

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Ethical Behavior
Scientific Fraud

being objective
making up measurements

making conclusions on the
changing results
basis of tests and
measurements

sharing results
taking credit for others’
work

Describe how fraud in scientific research could affect other
scientists who research in ethical ways. Accept all reasonable responses.

Fraud could mislead other scientists. It could cause them to base their own experiments

on inaccurate information.

SYNTHESIZE IT

This note-taking guide is designed to
help you succeed in learning science
content. Each chapter includes:

Language-Based Activities
Activities cover the content
in your science book including
vocabulary, writing, note-taking,
and problem solving.

Science Journal
Write about what
you know.

Writing Activities
These activities help you think
about what you’re learning
and make connections to
your life.

Vocabulary Development
Vocabulary words help you to better
understand your science lessons. Learning
the Academic Glossary can help you score
higher on standardized tests.

Anticipation Guide/KWL Charts
Think about what you already know
before beginning a lesson and
identify what you would like
to learn from reading.

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Georgia Science, Grade 8
vii

Define the four types of factors in a science experiment. Identify
and describe each of them below.

Summarize transferable technology by defining the term. Then
provide examples by filling out the graphic organizer below.

Transferable technology is

.

Radar and Sonar

the military

weather,
Earth’s structures

medicine and space

originally
developed for

are now
used to
study

one situation that is transferred to solve other problems

technology designed for

the variable that you change
Independent
Variable

variables that do not change
Constants

the variable being measured
Dependent
Variable

the standard to which results can
be compared
Control

Section 1 Science All Around (continued)

Working in
the Lab

I found this information
on page
.

SE, pp. 9–11
RE, pp. 4–5

Technology

I found this information
on page
.

SE, p. 14
RE, p. 5

Name
Date

4
The Nature of Science

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Identify three objects in your home or school that have not
been affected by technology. Accept all reasonable responses.

Almost everything is affected by technology in its construction or its parts. Students

should appreciate the importance of technology.

SYNTHESIZE IT

The Nature of Science
Chapter Wrap-Up

Now that you have read the chapter, think about what you have learned and complete
the table below. Compare your previous answers with these.

1. Write an A if you agree with the statement.

2. Write a D if you disagree with the statement.

Name
Date

After reading this chapter, identify three things that you have
learned about the nature of science. Accept all reasonable responses.

1. Testing is an important part of scientific research. 2. A scientific hypothesis can

become a theory if it has been well tested and is supported by many experiments.

3. It is important to conduct scientific research in an ethical way.

SUMMARIZE IT

Review
Use this checklist to help you study.

Review the information you included in your Foldable.

Study your Science Notebook on this chapter.

Study the definitions of vocabulary words.

Review daily homework assignments.

Re-read the chapter and review the charts, graphs, and illustrations.

Review the Self Check at the end of each section.

Look over the Chapter Review at the end of the chapter.

• An important part of science is testing, or
A SE, p. 9

experimenting.
RE, p. 3

• Technology is useful only in the situation for
D SE, p. 14

which it was designed.
RE, p. 5

• People began studying weather in the 1800s.
D SE, p. 16

RE, p. 7

• Science can answer all of the questions that
D SE, p. 20

can be asked.
RE, p. 10

The Nature of Science
After You
Read

8
The Nature of Science

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Summarize why it was important for scientists to solve the mystery
of the tsunami that struck Japan, on January 27,1700.

By solving the mystery, scientists discovered that very large

earthquakes can happen in the Pacific Northwest. Knowing that

earthquakes of that size are possible in that area can help people

prepare for the possibility of another similarly large earthquake.

Sequence the scientific methods used to solve a scientific problem
by completing the graphic organizer below.

Distinguish topics that Earth scientists study by listing specific
topics identified in this section.

1.
7.

2.
8.

3.
9.

4.
10.

5.
11.

6.
12.
objects in space
fossils

ocean water
earthquakes

weather
volcanoes

climates
soil

mountains
minerals

maps
rocks

Identify a problem.

Gather information.

Make a hypothesis.

Test the hypothesis.

Analyze the results.

Draw conclusions.

Section 1 Science All Around (continued)

Mysteries and
Problems

I found this information
on page
.

SE, pp. 6–7
RE, pp. 1–2

Scientific
Methods

I found this information
on page
.

SE, p. 8
RE, p. 3

Science

I found this information
on page
.

SE, p. 9
RE, p. 3

Name
Date

The Nature of Science
3

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Chapter Wrap-Up
This brings the information together
for you. Revisiting what you thought
at the beginning of the chapter provides
another opportunity for you to discuss
what you have learned.

Note-Taking Based on
the Cornell Two-Column Format
Practice effective note-taking through
the use of graphic organizers, outlines,
and written summaries.

Review Checklist
This list helps you assess what
you have learned and prepare
for your chapter tests.

Graphic Organizers
A variety of visual organizers help you
to analyze and summarize information
and remember content.

Construct the Foldable as directed at the beginning of this chapter.

The Nature of Science

Before You Read

Before you read the chapter, respond to these statements.

1. Write an A if you agree with the statement.
2. Write a D if you disagree with the statement.

Name
Date

• Science and technology are independent of

one another.

• Only scientists use science skills.

• Scientific theories can change if new information

becomes available.

• Science experiments that are done by professional

scientists do not need to be repeated.

Write down three examples of science in your everyday life.

Science Journal

Before You
The Nature of Science
Read

The Nature of Science
1

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

New

Vocabulary

Review

Vocabulary

Academic
Vocabulary

Name
Date

The Nature of Science
Section 1 What is science?

2
The Nature of Science

Skim through Section 1 of your text. Write three questions that
come to mind from reading the headings and looking at the
illustrations.

1.

2.

3.

Define theory using your book or a dictionary. Write a sentence
about a theory you have heard people talk about in everyday life.

Write the correct key term from your text next to each definition.

an explanation of a pattern observed repeatedly in the natural
world

a way of learning more about the natural world

a collection of structures, cycles, and processes that relate to and
interact with each other

a rule that describes a pattern in nature

Use a dictionary to help you write a scientific definition of the
word cycle.

theory

cycle

Complete the graphic organizer to show what may happen
to a scientific theory when new data are discovered. Use the
following phrases:

• Evaluate scientific theory.
• Theory is modified.

• Theory is discarded.
• Theory stays same.

Synthesize information from your book to list some of the
structures, cycles, and processes in your school day.

Choose at least one structure, one cycle, and one process from your
list and describe the ways they interact.

New data

New data

do not

fit theory.

New data

fits

theory.
Theory is modified.

Structures
Cycles
Processes

Section 1 What is science? (continued)

Learning About

the World

I found this information
on page
.

Systems in

Science

I found this information
on page
.

Name
Date

The Nature of Science
3

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Classify which branch of science—physical science, Earth science,
or life science—includes each of the following examples. Then, write
one additional example studied by that science.

Complete the following paragraph about the relationship between
science and technology.

is a way to learn about the natural world.

To use these answers for helping people, however, they must be

applied in some way.
is the practical use of

in our everyday lives.

Section 1 What is science? (continued)

The Branches

of Science

I found this information
on page
.

Science and

Technology

I found this information
on page
.

Name
Date

4
The Nature of Science

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Example
Branch of
Additional

Science
Example

Soil

Fish

Light

Meteors

Chemical reactions

Body systems

Plants

Clouds

Write about a time that you used science to figure out a problem

in your everyday life. Include an additional question about this topic that you might
like to investigate.

CONNECT IT

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Review

Vocabulary

Academic
Vocabulary

Name
Date

The Nature of Science
Section 2 Science in Action

New

Vocabulary

The Nature of Science
5

observation

hypothesis

infer

controlled experiment

variable

constant

chart

Skim the headings in Section 2. Then make three predictions about
what you will learn.

1.

2.

3.

Define observation and give an example of an observation you
made today.

Use your book or a dictionary to define the following key terms.

Use a dictionary to define chart as it refers to science.

Connect concepts by completing the concept map below about
scientific methods.

Complete the outline below by writing answers on the lines.

Making Conclusions and Communicating

I. Conclusions

A. Definition of conclusion

1.

2.

B. Reasons why scientists often test the conclusions of

another scientist

1.

2.

II. Communicating—Reasons why it is important for scientists

to communicate

A.

B.

Scientific
Methods

often begin
with

lead to results
and judgments
called

can include
experiments
to collect

include
possible
answers
called

Section 2 Science in Action (continued)

Science Skills

I found this information
on page
.

Drawing

Conclusions

I found this information
on page
.

Name
Date

6
The Nature of Science

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Compare and contrast types of variables by writing a sentence
that describes each type.

Analyze each procedure below and write the precautions you
should take to keep safe.

Heating a liquid on a hot plate:

Going outside to observe nature:

Handling plants or animals in the lab:

Section 2 Science in Action (continued)

Experiments

I found this information
on page
.

Laboratory

Safety

I found this information
on page
.

Name
Date

The Nature of Science
7

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Think of a scientific question that you would like to answer.

Then, write three hypotheses, or possible answers, to your question. How could you
test your hypotheses?

CONNECT IT

How Variables Change

Type of Variable
Description

Independent
variable

Dependent
variable

Constant