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Laboratory Manual Laboratory Manual Student Edition A Glencoe Program Hands-On Learning: Teacher Resources: Laboratory Manual, SE/TE Lesson Plans Forensics Laboratory Manual, SE/TE Block Scheduling Lesson Plans CBL Laboratory Manual, SE/TE Spanish Resources Small-Scale Laboratory Manual, SE/TE Section Focus Transparencies and Masters ChemLab and MiniLab Worksheets Math Skills Transparencies and Masters Teaching Transparencies and Masters Review/Reinforcement: Solutions Manual Study Guide for Content Mastery, SE/TE Solving Problems: A Chemistry Handbook Technology: Reviewing Chemistry Chemistry Interactive CD-ROM Guided Reading Audio Program Vocabulary PuzzleMaker Software, Windows/Macintosh Applications and Enrichment: Glencoe Science Web site: Challenge Problems science.glencoe.com Supplemental Problems Assessment: Chapter Assessment MindJogger Videoquizzes (VHS) TestCheck Software, Windows/Macintosh 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 the Chemistry: Matter and Change program. 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, OH 43240-4027 ISBN 0-07-824524-9 Printed in the United States of America. 3 4 5 6 7 8 9 10 045 09 08 07 06 05 04 03 02 LABORATORY MANUAL Contents How to Use This Laboratory Manual . .vii Writing a Laboratory Report . .viii Laboratory Equipment . .x Safety in the Laboratory . .xiii Safety Symbols . .xiv Laboratory Activities CHAPTER 1 Introduction to Chemistry 1.1 Laboratory Techniques and Lab Safety . 1 1.2 Effective Use of a Bunsen Burner . 5 CHAPTER 2 Data Analysis 2.1 Density . 9 2.2 Making a Graph . 13 CHAPTER 3 Matter—Properties and Changes 3.1 The Density of Wood . 17 3.2 Properties of Water . 21 CHAPTER 4 The Structure of the Atom 4.1 Simulation of Rutherford’s Gold Foil Experiment . 25 4.2 Half-life of Barium-137m . 29 CHAPTER 5 Electrons in Atoms 5.1 The Photoelectric Effect . 33 5.2 Electron Charge to Mass Ratio . 37 CHAPTER 6 The Periodic Table and Periodic Law Copyright ©Copyright Glencoe/McGraw-Hill, Companies, of the McGraw-Hill a division Inc. 6.1 Properties of the Periodic Table . 41 6.2 Periodic Trends in the Periodic Table . 45 Laboratory Manual Chemistry: Matter and Change iii LABORATORY MANUAL CHAPTER 7 The Elements 7.1 Is there potassium in coffee? . 49 7.2 The Periodic Puzzle . 53 CHAPTER 8 Ionic Compounds 8.1 Properties of Ionic Compounds . 57 8.2 Formation of a Salt . 61 CHAPTER 9 Covalent Bonding 9.1 Covalent Bonding in Medicines . 65 9.2 Covalent Compounds . 69 CHAPTER 10 Chemical Reactions 10.1 Single-Replacement Reactions . 73 10.2 Double-Replacement Reactions . 77 CHAPTER 11 The Mole 11.1 Estimating the Size of a Mole . 81 11.2 Mole Ratios . 85 CHAPTER 12 Stoichiometry 12.1 Observing a Limiting Reactant . 89 12.2 Determining Reaction Ratios . 93 CHAPTER 13 States of Matter 13.1 Freezing Bacteria . 97 13.2 Boiling Points . 101 CHAPTER 14 Gases 14.1 Charles’s Law . 105 14.2 Boyle’s Law . 109 Copyright ©Copyright Glencoe/McGraw-Hill, Companies, of the McGraw-Hill a division Inc. iv Chemistry: Matter and Change Laboratory Manual LABORATORY MANUAL CHAPTER 15 Solutions 15.1 Making a Solubility Curve . 113 15.2 Freezing Point Depression . 117 CHAPTER 16 Energy and Chemical Change 16.1 Heats of Solution and Reaction . 121 16.2 Heat of Combustion of Candle Wax . 125 CHAPTER 17 Reaction Rates 17.1 The Rate of a Reaction . 129 17.2 Surface Area and Reaction Rate . 133 CHAPTER 18 Chemical Equilibrium 18.1 Reversible Reactions . 137 18.2 Equilibrium . 141 CHAPTER 19 Acids and Bases 19.1 Acids, Bases, and Neutralization . 145 19.2 Determining the Percent of Acetic Acid in Vinegar . 149 CHAPTER 20 Redox Reactions 20.1 Electron-Losing Tendencies of Metals . 153 20.2 Determining Oxidation Numbers . 157 CHAPTER 21 Electrochemistry 21.1 Electrolysis of Water . 161 21.2 Electroplating . 165 CHAPTER 22 Hydrocarbons 22.1 Isomerism . 169 22.2 The Ripening of Fruit with Ethene . 173 Copyright ©Copyright Glencoe/McGraw-Hill, Companies, of the McGraw-Hill a division Inc. Laboratory Manual Chemistry: Matter and Change v LABORATORY MANUAL CHAPTER 23 Substituted Hydrocarbons and Their Reactions 23.1 The Characterization of Carbohydrates . 177 23.2 Polymerization Reactions . 181 CHAPTER 24 The Chemistry of Life 24.1 Denaturation . 185 24.2 Saturated and Unsaturated Fats . 189 CHAPTER 25 Nuclear Chemistry 25.1 Radioisotope Dating . 193 25.2 Modeling Isotopes . 197 CHAPTER 26 Chemistry in the Environment 26.1 Organisms That Break Down Oil . 201 26.2 Growth of Algae as a Function of Nitrogen Concentration . 205 Copyright ©Copyright Glencoe/McGraw-Hill, Companies, of the McGraw-Hill a division Inc. vi Chemistry: Matter and Change Laboratory Manual LABORATORY MANUAL How to Use This Laboratory Manual Chemistry is the science of matter, its properties, and changes. In your classroom work in chemistry, you will learn a great deal of the information that has been gathered by scientists about matter. But, chemistry is not just information. It is also a process for finding out more about matter and its changes. Laboratory activities are the primary means that chemists use to learn more about matter. The activities in the Laboratory Manual require that you form and test hypotheses, measure and record data and observations, analyze those data, and draw conclusions based on those data and your knowledge of chemistry. These processes are the same as those used by professional chemists and all other scientists. Organization of Activities • Introduction Following the title and number of each activity, an introduction provides a background discussion about the problem you will study in the activity. • Problem The problem to be studied in this activity is clearly stated. • Objectives The objectives are statements of what you should accomplish by doing the investigation. Recheck this list when you have finished the activity. • Materials The materials list shows the apparatus you need to have on hand for the activity. • Safety Precautions Safety symbols and statements warn you of potential hazards in the laboratory. Before beginning any activity, refer to page xiv to see what these symbols mean. • Pre-Lab The questions in this section check your knowledge of important concepts needed to complete the activity successfully. • Procedure The numbered steps of the procedure tell you how to carry out the activity and sometimes offer hints to help you be successful in the laboratory. Some activities have CAUTION statements in the procedure to alert you to hazardous substances or techniques. • Hypothesis This section provides an opportunity for you to write down a hypothesis for this activity. • Data and Observations This section presents a suggested table or form for collecting your laboratory data. Always record data and observations in an organized way as you do the activity. • Analyze and Conclude The Analyze and Conclude section shows you how to perform the calculations necessary for you to analyze your data and reach conclusions. It provides ques- tions to aid you in interpreting data and observations in order to reach an experimental result. You are asked to form a scientific conclusion based on what you actually observed, not what “should have happened.” An opportunity to analyze possible errors in the activity is also given. • Real-World Chemistry The questions in this section ask you to apply what you have learned in Copyright ©Copyright Glencoe/McGraw-Hill, Companies, of the McGraw-Hill a division Inc. the activity to other real-life situations. You may be asked to make additional conclusions or research a question related to the activity. Laboratory Manual Chemistry: Matter and Change vii LABORATORY MANUAL Writing a Laboratory Report When scientists perform experiments, they make observations, collect and analyze data, and formulate generalizations about the data. When you work in the laboratory, you should record all your data in a laboratory report. An analysis of data is easier if all data are recorded in an organized, logical manner. Tables and graphs are often used for this purpose. Title: The title should clearly describe the topic of the report. Hypothesis: Write a statement to express your expectations of the results and as an answer to the problem statement. Materials: List all laboratory equipment and other materials needed to perform the experiment. Procedure: Describe each step of the procedure so that someone else could perform the experiment following your directions. Results: Include in your report all data, tables, graphs, and sketches used to arrive at your conclusions. Conclusions: Record your conclusions in a paragraph at the end of your report. Your conclusions should be an analysis of your collected data. Read the following description of an experiment. Then answer the questions. All plants need water, minerals, carbon dioxide, sunlight, and living space. If these needs are not met, plants cannot grow properly. A scientist wanted to test the effectiveness of different fertilizers in supplying needed minerals to plants. To test this idea, the scientist set up an experiment. Three containers were filled with equal amounts of potting soil and one healthy bean plant was planted in each of three containers. Container A was treated with Fertilizer A, Container B was treated with Fertilizer B, and Container C did not receive any fertilizer. All three containers were placed in a well-lit room. Each container received the same amount of water every day for 2 weeks. The scientist measured the heights of the growing plants every day. Then the average height of the plants in each container each day was calculated and recorded in Data Table 1.
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