Table Of Content

Reading 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 ni a p m Chapter 23 Chemical Reactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .412 Co Hill Chapter 24 Solutions,Acids,and Bases . . . . . . . . . . . . . . . . . . . . . . . . . . . .432 w- a McGr Chapter 25 Nuclear Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .452 e of Th Chapter 26 Stars and Galaxies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .474 n o divisi a Hill, w- a Gr Mc e/ o nc e Gl by © ht g pyri Co iii 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 understand, 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 a p m 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 w- a study guides. Or, students can glue maps, charts, tables, photocopied activity sheets, Gr Mc internet print-outs, and any other activities using a whole sheet of paper onto these e h projects. of T n o 4. The Accordion Project lends itself to vertical Foldables such as those with two, divisi a three, four, or more tabs. Two quarter sheets of notebook paper also fit on each of Hill, w- the four sections of this project. a Gr Mc HINT: If you would like to place a whole sheet of paper into this project, fold it in e/ o nc half or into fourths and then glue the folded paper onto one of the four sections. Gle by © ht g pyri Co iv 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. nc. es, I ni a p m Co Hill w- a Gr Mc e h of T n o divisi a Hill, w- a Gr Mc e/ o nc e Gl by © ht g pyri Co v 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 p m the natural world. Co Hill w- What are the major categories of science? Gra Mc Science covers many different topics.These topics fall he ●A Build Vocabulary of T under three main categories: life science,Earth science,and n o Make the following Foldable to physical science.Life science is the study of living things. divisi htheilsp s yeoctuio lena. rYno kue wy itlel rnmees dfr toom Earth science is the study of Earth and space.Physical science w-Hill, a make more than one Foldable. is the study of matter and energy.In this book,you will study Gra Mc mainly physical science.You also will learn how these three e/ o Variable nc DeVpaerinadbelent main categories sometimes overlap. © by Gle 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 methods. 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Interpret Why are there Gl by (cid:105)(cid:100)(cid:21)(cid:101)(cid:103)(cid:100)(cid:105)(cid:90)(cid:88)(cid:105)(cid:21)(cid:105)(cid:93)(cid:90)(cid:21)(cid:98)(cid:100)(cid:89)(cid:90)(cid:97)(cid:21)(cid:104)(cid:101)(cid:86)(cid:88)(cid:90)(cid:21)(cid:104)(cid:93)(cid:106)(cid:105)(cid:105)(cid:97)(cid:90)(cid:21) two arrows leading to © ht (cid:87)(cid:90)(cid:105)(cid:105)(cid:90)(cid:103)(cid:21)(cid:105)(cid:93)(cid:86)(cid:99)(cid:21)(cid:100)(cid:105)(cid:93)(cid:90)(cid:103)(cid:21)(cid:98)(cid:86)(cid:105)(cid:90)(cid:103)(cid:94)(cid:86)(cid:97)(cid:104)(cid:35) different parts of the g pyri chart at the bottom? Co (cid:61)(cid:110)(cid:101)(cid:100)(cid:105)(cid:93)(cid:90)(cid:104)(cid:94)(cid:104)(cid:21)(cid:99)(cid:100)(cid:105)(cid:21)(cid:104)(cid:106)(cid:101)(cid:101)(cid:100)(cid:103)(cid:105)(cid:90)(cid:89) (cid:61)(cid:110)(cid:101)(cid:100)(cid:105)(cid:93)(cid:90)(cid:104)(cid:94)(cid:104)(cid:21)(cid:104)(cid:106)(cid:101)(cid:101)(cid:100)(cid:103)(cid:105)(cid:90)(cid:89) (cid:73)(cid:90)(cid:104)(cid:105)(cid:21)(cid:100)(cid:105)(cid:93)(cid:90)(cid:103)(cid:21)(cid:88)(cid:90)(cid:103)(cid:86)(cid:98)(cid:94)(cid:88)(cid:21)(cid:98)(cid:86)(cid:105)(cid:90)(cid:103)(cid:94)(cid:86)(cid:97)(cid:104)(cid:21) (cid:105)(cid:100)(cid:21)(cid:104)(cid:90)(cid:90)(cid:21)(cid:108)(cid:93)(cid:94)(cid:88)(cid:93)(cid:21)(cid:100)(cid:99)(cid:90)(cid:21)(cid:101)(cid:103)(cid:100)(cid:105)(cid:90)(cid:88)(cid:105)(cid:104)(cid:21)(cid:105)(cid:93)(cid:90)(cid:21) (cid:98)(cid:100)(cid:89)(cid:90)(cid:97)(cid:21)(cid:104)(cid:101)(cid:86)(cid:88)(cid:90)(cid:21)(cid:104)(cid:93)(cid:106)(cid:105)(cid:105)(cid:97)(cid:90)(cid:21)(cid:87)(cid:90)(cid:104)(cid:105)(cid:35) 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 nc. to test a hypothesis. Scientists may also use an experiment es, I ni to test a hypothesis. The experiment looks at how one thing pa m affects another under controlled conditions. NASA scientists Hill Co built model space shuttles and covered them with various w- a Gr materials. They tested the models in simulated re-entry Mc e h environments to see which material gave the best protection. of T n o Variable An experiment usually has at least two variables. A divisi a variable is a factor that can cause a change in the results of Hill, w- a an experiment. Suppose you set up an experiment to see Gr Mc which fertilizer makes plants grow biggest. First, you need to e/ o nc think of all the factors that can make a plant grow bigger. Gle by These might include the type of plant, amount of sunlight, © 4. kDinedfsi nofe vWarhiaabtl easre t hthate atrweo amInou tnhtis o efxpweartiemr,etnytp,et hoef asmoiol,uanntd o famgroouwntht oisf ofenret ivliazreira.ble.It Copyright tested in experiments? is a dependent variable because its value changes according to the changes in other variables.The other variable is the amount of fertilizer.The independentvariable is changed to see how much it affects the dependent variable. 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. ni mpa Drawing Conclusions Scientists look at their data and decide 6. Listtwo reasons why data Co Hill if the data support the hypothesis. If the data is the same must be organized. w- a Gr after many experiments, the hypothesis is supported. If the Mc he hypothesis isn’t supported, scientists may change it or the of T n experiment. o divisi Sometimes others don’t agree with the conclusions,so they a Hill, design new experiments to test the hypothesis.In time,data w- Gra will support a valid hypothesis. Mc e/ nco Being Objective Scientists must avoid a bias. A bias occurs e Gl by in an experiment when a scientist expects something to © ht happen and lets this influence how the results are viewed. g pyri Scientists try to reduce bias whenever they can by doing Co the experiment many times and keeping careful notes 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. to be flying a plane.The pilot can test different ways to solve ni a p m problems.The simulator reacts the same way a real plane does Co Hill when it flies,but there is no danger to either the pilot w- a Gr or a plane.In the figure below,you can see an example of a Mc e flight simulator. of Th n o divisi a Hill, w- Picture This Gra Mc 8. Identifyand list three ncoe/ e differences between a Gl by flight simulator and a real © ht airplane. pyrig Co S BI R O C 6 CHAPTER 1 The Nature of Science