Table Of ContentReading Essentials
An Interactive Student Textbook
gpescience.com
Glencoe Science
To the Student
In today’s world, knowing science is important for thinking critically, solving problems, and
making decisions. But understanding science sometimes can be a challenge.
Reading Essentials takes the stress out of reading, learning, and understanding science. This
book covers important concepts in science, offers ideas for how to learn the information, and
helps you review what you have learned.
In each chapter:
• Before You Read sparks your interest in what you’ll learn and relates it to your world.
• Read to Learn describes important science concepts with words and graphics. Next to the
text you can find a variety of study tips and ideas for organizing and learning information:
• The Study Coach offers tips for getting the main ideas out of the text.
• Foldables™ Study Organizers help you divide the information into smaller, easier-
to-remember concepts.
• Reading Checks ask questions about key concepts. The questions are placed so you
know whether you understand the material.
• Think It Over elements help you consider the material in-depth, giving you an
opportunity to use your critical-thinking skills.
• Picture This questions specifically relate to the art and graphics used with the text.
You’ll find questions to get you actively involved in illustrating the concepts you
read about.
• Applying Math reinforces the connection between math and science.
• Use After You Read to review key terms and answer questions about what you have
learned. The Mini Glossary can assist you with science vocabulary. Review questions
focus on the key concepts to help you evaluate your learning.
See for yourself. Reading Essentials makes science easy to understand and enjoyable.
Copyright © by the McGraw-Hill Companies, Inc. All rights reserved. Except as permitted under the United
States Copyright Act, no part of this publication may be reproduced or distributed in any form or by any
means, or stored in a database or retrieval system, without the prior written permission of the publisher.
Send all inquiries to:
Glencoe/McGraw-Hill
8787 Orion Place
Columbus, OH 43240
ISBN 0-07-872557-7
Printed in the United States of America
1 2 3 4 5 6 7 8 9 10 047 09 08 07 06 05
Table of Contents
To the Student . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .ii
Chapter 1 The Nature of Science . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Chapter 2 Science,Technology,and Society . . . . . . . . . . . . . . . . . . . . . . . .20
Chapter 3 Motion,Acceleration,and Forces . . . . . . . . . . . . . . . . . . . . . . . .36
Chapter 4 The Laws of Motion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
Chapter 5 Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
Chapter 6 Work and Machines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82
Chapter 7 The Earth-Moon-Sun System . . . . . . . . . . . . . . . . . . . . . . . . . .100
Chapter 8 The Solar System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118
Chapter 9 Heat and States of Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . .140
Chapter 10 Waves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .160
Chapter 11 Sound and Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .178
Chapter 12 Earth’s Internal Processes . . . . . . . . . . . . . . . . . . . . . . . . . . . . .200
Chapter 13 Electricity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .220
Chapter 14 Magnetism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .238
Chapter 15 Electromagnetic Radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . .254
Chapter 16 Energy Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .272
Chapter 17 Weather and Climate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .292
Chapter 18 Classification of Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .314
Chapter 19 Properties of Atoms and the Periodic Table . . . . . . . . . . . . . .326
Chapter 20 Earth Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .344
nc. Chapter 21 Earth’s Changing Surface . . . . . . . . . . . . . . . . . . . . . . . . . . . . .364
es, I Chapter 22 Chemical Bonds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .388
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Foldables
Foldables™ are easy-to-make, three-dimensional, interactive graphic organizers that
students create out of simple sheets of paper. These unique hands-on tools for studying
and reviewing were created exclusively for Glencoe by education specialist Dinah Zike.
Research shows (Bransford, 1979; Corno, 1994), study strategies help students under-
stand, organize, remember and apply new information presented in science textbooks.
Some study strategies include concept mapping, highlighting, outlining, note taking,
summarizing, and underlining (Peverly, Probst, Graham & Shaw, 2003).
Organizing Foldables to make Chapter Projects:
For each chapter, students use 11"(cid:1)17" paper or 12"(cid:1)18" art paper to make projects
that act as portfolios for collecting student-made Foldables. These cumulative projects
act as study guides and are perfect for continuing to immerse students in concepts and
vocabulary as they progress through a chapter.
1. Have students write their names, date, period/class, and a main idea or a title on the
front of each chapter project. Some students might choose to illustrate the cover
using any of the following: original or traced illustrations or graphics, internet
printouts, photocopied pictures, original photographs, newspaper articles pertaining
to topic studied, or diagrams, tables, or charts.
2. Quarter sheets and half-sheets of notebook paper are used in place of 3"(cid:1)5" and
4"(cid:1)7" index cards. These small sheets of paper are inexpensive and perfect for
recording terms and definitions, taking class notes and main ideas, outlining key
points, making concept maps or webs, sketching diagrams or observations, and
writing general information on a science person, place, or thing.
3. Three of the five projects (Bound Book Project, Half-Book Project, and Shutterfold es, Inc.
Project) lend themselves to the use of whole sheets of notebook paper or photocopy ni
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paper. Single or multiple sheets of paper can be stapled or braided onto these Co
projects. This allows essays and in-depth research projects to be included in chapter Hill
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Organizing Foldables to make Chapter Projects:
continued
5. Pocket Projects are perfect for organizing and storing student work. Fold whole
sheets of paper and student-made Foldables so they will fit into the two or three
pockets of the chapter project. These act as portfolios for student work and notes.
6. Students can use the ideas presented in these chapters to design their own student
aids and project formats. It is much easier to store and display a Foldables project
than a poster board project.
Teaching Tips for Foldables
Do not ask middle school and high school students to carry glue and scissors from class
to class. Instead, set up a small table or rolling cart in the back of the classroom and
provide a few containers of glue, several pairs of scissors, containers of colored pencils,
a stapler, and anything else the students might need.
Turn one-gallon freezer bags into student portfolios. Students can carry their portfolios
in their notebooks if they place strips of two-inch clear tape along one side and punch
three holes through the taped edge. Cut bottom corners off the bag so it won’t hold air
and will stack and store easily.
For additional information on Dinah Zike publications (Dinah Zike’s Teaching Science
with Foldables) or workshops call 1-800-99DINAH or contact www.dinah.com.
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The Nature of Science
chapter
1
The Methods of Science
●
section 1
Before You Read
What You’ll Learn
■how scientists solve
When you hear the word scientist, what comes to mind?
problems
Brainstorm some words that describe a scientist.Write them
■why scientists use
variables on the lines below.
■how to compare and
contrast science and
technology
Read to Learn
Identify Highlight each
What is science?
heading that is a question. Use
a different color of marker to
Science is not just a subject in school.Science is a way of
highlight the answers to the
studying the world.The word science comes from a Latin
questions.
word that means “knowledge.”Science is a way to learn or
gain knowledge by observing and investigating.
Nature follows a set of rules.The rules for understanding
how the human body works are complicated.The rules for
understanding the pattern of Earth spinning once every 24 h es, Inc.
on its axis are simpler.Scientists ask questions to learn about ani
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IndVCeaoprnieasnbtadlenetnt HoScwie ndtoifiec se xspclaineanticones ehexlpp leaxpinla inna thteu rneat?ural world. Copyright
Control Scientists investigateandusetechnologytogetnew information.
SMceietnhtoifdic Sometimes,this new information causes scientific explanations
Hypothesis to change.In the 1700s,most scientists thought heat was a fluid.
Experiment
After many studies,they concluded heat is not a fluid.
2 CHAPTER 1 The Nature of Science
Scientific Methods
A scientific method is a set of steps used in an investigation.
Scientists follow steps similiar to those listed below when
doing an investigation.These steps guide the scientist.Some
steps may be repeated.Other steps may be skipped.The
flowchart below shows six common steps found in scientific
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Reading Essentials 3
Stating a Problem Many scientific investigations begin with
a question about how or why something happens in nature.
The problem is stated as a “how” or “why” question.
Sometimes a question is asked because scientists want to
improve upon something. Early work on guided missiles
showed that the nose cones needed a material to protect
them from heat. Later, National Aeronautic and Space
Administration (NASA) scientists wanted to find a material
to protect the space shuttle from the heat and forces of
re-entry into Earth’s atmosphere.
Researching and Gathering Information It is important
to study a problem before any testing is done. Sometimes
someone has already solved a similar problem. NASA
3. Research List two
scientists gathered information about melting points and
places where you might
other properties of various materials that might be used.
find information on the
They also performed tests on newly created materials.
development of the
space shuttle.
Forming a Hypothesis A hypothesis is a possible
explanation for a question or problem based on what you
know and what you observe. A scientist who forms a
hypothesis must be certain it can be tested. NASA scientists
knew that a certain ceramic material had been used to protect
the nose cones of guided missiles. They hypothesized that a
ceramic material might also protect the space shuttle.
Testing a Hypothesis Some hypotheses are tested by
making observations. Building a model may be the best way
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is a dependent variable because its value changes according
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amount of fertilizer.The independentvariable is changed to
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4 CHAPTER 1 The Nature of Science
Constants and Controls To keep an investigation fair, all
other factors must be the same. A constant is a factor in an
experiment that does not change. In the fertilizer experiment,
the constants are the amount of water and sunlight the plants
get and the temperature at which the plants are kept. These
are the same for all plants tested. Three plants get different
amounts of fertilizer, which is the independent variable.
A control is used to compare the results of the experiment.
One plant is a control and does not get any fertilizer,but does
get the same sunlight,water,and temperature as the other 5. Classify Is the plant that
plants.Suppose after several days that the control plants grow receives no fertilizer in the
plant experiment a variable,
between 2 and 3 cm.If the unfertilized plant grows only 1.5
a constant, or a control?
cm,you might infer that the greater growth of the fertilized
plants was caused by the fertilizer.
Analyze the Data An important part of any experiment is
recording observations and organizing information. All
results and observations should be recorded during an
experiment. Many important discoveries have been made
from unexpected results. The information or data should be
organized into an easy-to-read table or graph. Later in this
chapter, you will learn how to show your data.
Understanding what the data and observations mean is
also important.The data must be organized logically.Poorly
organized data may lead to a wrong conclusion.Scientists
share their data through reports and meetings.Scientists may
disagree about certain data,no matter how well the data is
es, Inc. presented.
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about observations. Also, other scientists repeat the same
experiment to see if they get the same results.
Reading Essentials 5
Visualizing with Models
Sometimes,scientists cannot see everything they are testing.
They might be studying something too large or too small to
see.It might even take too much time to see completely.In
these cases,scientists use models.A model represents an idea,
event,or object to help people better understand it.A model
may be a physical object such as a scaled-down version of the
space shuttle.A model can also be represented by a drawing
on paper or by a computer program.
Models in History Models have been used throughout
history. Lord Kelvin, a scientist who lived in England in the
1800s, was famous for making models. To model his idea of
how light moves through space, he put balls in a bowl of
jelly. He asked people to move the balls with their hands.
Kelvin’s work explaining heat and temperature is still used
today.
7. Explain What are What are high-tech models?
models?
Scientific models don’t have to be something you can touch.
Many scientists use computers to build models.Computer
models are used to solve difficult mathematical equations.
NASA uses computers in experiments with space flights to
solve equations that are too hard or would take too long to
solve by hand.
Another type of model is a simulator.A simulator can
create the conditions found in real life.For example,a flight
simulator is a model of an airplane.It can help a pilot pretend es, Inc.
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6 CHAPTER 1 The Nature of Science
