DOCSLIB.ORG

Eighth Grade Science Introduction

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Eighth Grade Science Introduction Eighth Grade Science Introduction This book belongs to: ______________________________________ CREDITS Unless otherwise noted, the contents of this book are licensed under the Creative Commons Attribution NonCommercial ShareAlike license. Detailed information about the license is available online at http://creativecommons.org/licenses/by-nc-sa/3.0/legalcode. Prior to making this book publicly available, we have reviewed its contents extensively to determine the correct ownership of the material and obtain the appropriate licenses to make the material available. We will promptly remove any material that is determined to be infringing on the rights of others. If you believe that a portion of this book infringes another’s copyright, contact Assistant Superintendent of Curriculum and Instruction. If you do not include an electronic signature with your claim, you may be asked to send or fax a follow-up copy with a signature. To file the notification, you must be either the copyright owner of the work or an individual authorized to act on behalf of the copyright owner. Your notification must include: 1. Identification of the copyrighted work, or in the case of multiple works at the same location, a representative list of such works at that site. 2. Identification of the material that is claimed to be infringing or to be the subject of infringing activity. You must include sufficient information, such as a specific page number or other specific identification, for us to locate the material. 3. Information for us to be able to contact the claimant (e.g., email, address, phone number). 4. A statement that the claimant believes that the use of the material has not been authorized by the copyright owner or an authorized agent. 5. A statement that the information in the notification is accurate and that the claimant is, or is authorized to act on behalf of, the copyright owner. This book is adapted from the excellent materials created by the CK-12 Foundation (http://ck12.org) which are licensed under the Creative Commons Attribution NonCommercial ShareAlike license. We express our gratitude to the CK-12 Foundation for their pioneering work on secondary science textbooks, without which the current book would not be possible. We would like to thank Utah’s State Department of Education for providing a model for Broken Arrow Public Schools. We also thank the amazing Broken Arrow Public Schools’ (BAPS) 8th Grade Science teachers whose collaborative efforts made the book possible. We also extend our appreciation to Skiatook Public Schools’ 8th Grade Science Teacher Angela Shoemate and for her contributions. This textbook is aligned with Oklahoma Academic Standards, BAPS and SPS Sequence of Instruction for 8th grade. Thank you for your commitment to science education! TABLE OF CONTENTS Chapter 1 Chemical Reactions 1.1 Chemical Reactions (MS-PS1-5) Page 4 1.2 Conservation of Mass (MS-PS1-5) Page 7 1.3 Endothermic and Exothermic Reactions (MS-PS1-6) Page 10 1.4 Chemical Reactions and Food (MS-LS1-7) Page 16 Chapter 2 Motion and Forces 2.1 Motion and Force (MS-PS2-2) Page 19 2.2 Newton’s First Law (MS-PS2-2) Page 24 2.3 Newton’s Second Law (MS-PS2-2) Page 27 2.4 Newton’s Third Law (MS-PS2-1) Page 30 Chapter 3 Waves 3.1 Waves Basics: Structure and Types (MS-PS4-2) Page 32 3.2 Mechanical Waves and Energy (MS—PS4-1) Page 39 3.3 Electromagnetic Waves (MS-PS4-2) Page 43 3.4 Waves and Transmitting Information (MS-PS4-3) Page 47 Chapter 4 Plate Tectonics 4.1 Earth’s Interior Material (MS-ESS2-2) Page 49 4.2 Early Theories (MS-ESS2-2 and MS-ESS2-3) Page 53 4.3 Theory of Plate Tectonics (MS-ESS2-2 and MS-ESS2-3) Page 58 Chapter 5 Natural Hazards 5.1 Volcanoes (MS-ESS2-2 and MS-ESS3-2) Page 67 5.2 Earthquakes (MS-ESS2-2 and MS-ESS3-2) Page 72 5.3 Caves and Sinkholes/Groundwater Erosion & Deposition (MS-ESS2-2 and MS-ESS3-2) Page 84 5.4 Glaciers and Mass Movement (MS-ESS2-1, MS-ESS2-2 and MS-ESS3-2) Page 87 5.5 Other Natural Hazards (MS-ESS2-2 and MS-ESS3-2) Page 90 Chapter 6 Minerals, Rocks, and the Rock Cycle 6.1 Minerals (MS-ESS2-1) Page 93 6.2 Rocks (MS-ESS2-1) Page 101 6.3 Weathering (MS-ESS2-1 and 2-2) Page 107 6.4 Erosion and Deposition (MS-ESS2-1 and 2-2) Page 111 6.5 Rocks and Processes of the Rock Cycle (MS-ESS2-1) Page 114 Chapter 7 Earth’s History 7.1 Fossils (MS-ESS-1-4, MS-LS4-1, MS-LS4-2) Page 117 7.2 Determining the Rock’s Age (MS-LS4-1) Page 124 7.3 Geological Time Scale (MS-ESS1-4) Page 130 Chapter 8 Human Impact and Resources 8.1 Resources (MS-ESS3-1) Page 133 8.2 Resource Availability (MS-ESS3-1) Page 140 8.3 Resources and Population Growth (MS-ESS3-4) Page 152 8.4 Sustaining and Remediating Resources (MS-ESS3-4) Page 159 8.5 Natural Resources and Synthetic Materials (MS-PS1-3) Page 166 1.1 Chemical Reactions This reading supports… MS-PS1-5: Develop and use a model to describe how the total number of atoms does not change in a chemical reaction and thus mass is conserved. Chemical Reactions No doubt you’ve seen changes like those pictured in figure to the left. What do all these changes have in common? They are all chemical changes in matter. In a chemical change, matter changes into a different substance with different properties. Chemical changes occur because of chemical reactions. You can see more examples of chemical changes at this URL: http://www.youtube.com/watch?v=66kuhJkQCVM (2:05). What Is a Chemical Reaction? A chemical reaction is a process in which some substances change into different substances. Substances that start a chemical reaction are called reactants. Substances that are produced in the reaction are called products. Reactants and products can be elements or compounds. A chemical reaction can be represented by this general equation: The yield arrow shows the direction in which the reaction occurs. The reaction may occur quickly or slowly. For example, foam shoots out of a fire extinguisher as soon as the lever is pressed. But it might take years for metal to rust. Evidence of Chemical Reactions Not all changes in matter involve chemical reactions. For example, there are no chemical reactions involved in changes of state. When liquid water freezes or evaporates, it is still water. No bonds are broken and no new products are formed. How can you tell whether a change in matter involves a chemical reaction? Often, there is evidence. Four common signs that a chemical reaction has occurred are: Change in color: The products are a different color than the reactants. Change in temperature: Heat is released or absorbed during the reaction. Production of a gas: Gas bubbles are released during the reaction. Production of a solid: A solid settles out of a liquid solution. The solid is called a precipitate. You can see examples of each type of evidence by the figure below and the following URL http://www.youtube.com/watch?v=gs0j1EZJ1Uc (9:57). Breaking and Reforming Chemical Bonds In chemical reactions, bonds break in the reactants and new bonds form in the products. The reactants and products contain the same atoms, but they are rearranged during the reaction. As a result, the atoms are in different combinations in the products than they were in the reactants. Look at the example in figure to the right. It shows how water forms. Bonds break in molecules of hydrogen and oxygen. Then new bonds form in molecules of water. In both reactants and products, there are four hydrogen atoms and two oxygen atoms. But the atoms are combined differently in water. Chemical Reactions Assessments: Essential Skill: Explanations of stability and change in natural or designed systems can be constructed by examining the changes over time and forces at different scales, including the atomic scale. 1. Draw and label an example of a chemical reaction. Be sure to define reactants, products, and yield arrow. (DOK 1) 2. Tina made a "volcano" by pouring vinegar over a "mountain" of baking soda. The wet baking soda bubbled and the temperature decreased. What facts would you select as supporting evidence that a chemical reaction occurred? Besides the evidence seen above, what is other evidence that a chemical reaction occurred? (DOK 3) 1.2 Conservation of Mass By the end of this reading, you should be able to… MS-PS1-5: Develop and use a model to describe how the total number of atoms does not change in a chemical reaction and thus mass is conserved. This oil-burning power plant is located in the middle of New York City. Its smokestacks are equipped with scrubbers. These are devices that remove many of the pollutants from the exhaust gases. But the smokestacks still release gases. Oil is a fossil fuel. Like all fossil fuels-and the living things from which they form-oil consists mostly of carbon. What happens to the carbon in a fossil fuel like oil when it burns? There doesn’t appear to be anything left from the fire. Is the carbon destroyed in the flames? Actually, the carbon still exists because matter can’t be destroyed. Matter is always conserved in chemical reactions. If you don’t believe it, watch this video: http://safeshare.tv/v/RHOC44LU8Nw Conservation of Mass If you build a campfire like this one, you start with a big pile of logs.
Load more

Recommended publications
  • Inglish Dikshineri = English
    Kriol – Inglish Dikshineri English – Kriol Dictionary Compiled and edited by Yvette Herrera Myrna Manzanares Silvana Woods Cynthia Crosbie Ken Decker Editor-in-Chief Paul Crosbie Belize Kriol Project Cover design: Adapted from Yasser Musa Cover photo: Courtesy Robert Spain at 2008 Crooked Tree Cashew Fest Illustrations in the Introduction are from The Art of Reading, SIL International Literacy Department SIL International provided linguistic consultancy to this publication of the Belize Kriol Project. The Belize Kriol Project is the language development arm of The National Kriol Council. www.sil.org The National Kriol Council House of Culture, Regent Street P.O. Box 2447 Belize City Belize www.kriol.org.bz Belize Kriol Project P.O. Box 2120 Office: 33 Central American Blvd. Belize City, Belize The first printing of this dictionary was in 2007 and was funded by The Ministry of Education and The National Institute of Culture and History House of Culture, Regent Street Belize City, Belize First Edition Copyright © 2007 Belize Kriol Project Second Printing 2009 ISBN # 978-976-95165-1-9 Printed by Print Belize Belmopan, Belize CONTENTS List of Abbreviations .......................................... iv Foreword by Sir Colville Young.............................v Preface ..................................................................... ix Acknowledgements.............................................. xi Introduction.............................................................1 Guide to Using the Dictionary...........................3 The
    [Show full text]
  • TOWARDS POSTAL EXCELLENCE the Report of the President's Commission on Postal Organization June 1968
    TOWARDS POSTAL EXCELLENCE The Report of The President's Commission on Postal Organization June 1968 \ ... ~ ~ ..;,. - ..~ nu. For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 - Price $1.25 2 THE PRESIDENT'S COMMISSION ON POSTAL ORGANIZATION I ~ FREDERICK R. KAPPEL-Chairman Ii Chairman, Board of Directors (retired) ) American Telephone and Telegraph Company GEORGE P. BAKER Dean Harvard University Graduate School of Business Administration DAVIn E. BELL Vice President The Ford Foundation FRED J. BORCH President General Electric Company DAVIn GINSBURG Partner Ginsburg and Feldman RALPH LAZARUS Chairman Board of Directors Federated Department Stores GEORGE MEANY President American Federation of Labor and Congress of Industrial Organizations J. IRWIN MILLER Chairman Board of Directors Cummins Engine Company W. BEVERLY MURPHY President Campbell Soup Company RUDOLPH A. PETERSON President Bank of America MURRAY COMAROW-Executive Director ii THE PRESIDENT'S COMMISSION ON POSTAL ORGANIZATION 1016 SIXTEENTH STREET, N.W., WASHINGTON, D.C. 20036 The President The White House Washington, D.C. 20500 Dear Mr. President: I have the honor of transmitting the Report of the President's Commission on Postal Organization in compliance with Executive Order 11341 dated April 8, 1967. You asked this Commission to "conduct the most searching and exhaustive review ever undertaken . ." of the American postal service. We have complied with your mandate. You asked us to "determine whether the postal system as presently organized is capable of meeting the demands of our growing economy and our expanding population." We have concluded that it is not. Our basic finding is that the procedures for administering the ordinary executive departments of Government are inappropriate for the Post Office.
    [Show full text]
  • Lesson 4 Temperature Change TEACHER GUIDE
    Lesson 4 Temperature change TEACHER GUIDE Lesson summary Students meet scientist Jason Williams, an industrial chemist who designs the materials and processes for making solar cells. He explains that during the summers, Antarctic days are very long, sometimes lasting a couple of weeks or more. That makes solar energy an abundant natural resource near the South Pole. Solar cells convert energy from the sun into electrical energy. Converting energy from one form to another is an important process. In the activity, students will conduct two chemical reactions that convert chemical energy into thermal energy. Key concepts + A change in temperature is a clue that a chemical reaction may have occurred. + When the temperature increases during a chemical reaction, it is called an exothermic reaction. + When the temperature decreases during a chemical reaction, it is called an endothermic reaction. + It takes energy to break chemical bonds in the reactants. + Energy is released when chemical bonds form in the products. Safety Be sure you and the students wear properly fitting goggles. Read and follow all safety warnings on the labels of the sodium bicarbonate, citric acid, calcium chloride, and universal indicator containers. Also follow the warnings on the packaging of the foot warmer. Have students wash their hands after the activity. Proper disposal At the end of the lesson, have students pour their used solutions in a waste container. The resulting solution from the final demo should be placed in this container, too. Then dispose of all of this liquid waste down the drain or according to local regulations. The left-over sodium bicarbonate, citric acid, and calcium chloride powders can be disposed of with the classroom trash.
    [Show full text]
  • Walker's Point Strategic Action Plan MILWAUKEE
    MILWAUKEE comprehensive Department of City Development Plan • June, 2015 Walker’s Point Strategic Action Plan A Plan for the Area ii Acknowledgments Neighborhood Associations and Continuum Architects + Planners Interest Groups Ursula Twombly, AIA, LEED AP Arts@Large Walker’s Point Association GRAEF The Mandel Group Greater Milwaukee Committee Larry Witzling, Principal The Harbor District Initiative Craig Huebner, Planner/Urban Designer 12th District Alderman Jose Perez University of Wisconsin - Milwaukee Urban Development Studio City of Milwaukee Department of City Development Carolyn Esswein, AICP, CNU-A, Faculty Member in Charge Rocky Marcoux, Commissioner Vanessa Koster, Planning Manager Sam Leichtling, Long Range Planning Manager Mike Maierle, former Long Range Planning Manager Greg Patin, Strategic Planning Manager Dan Casanova, Economic Development Specialist Janet Grau, Plan Project Manager Nolan Zaroff, Senior Planner GIS, Eco- nomic Development Jeff Poellmann, Planning Intern (Urban Design) Andrew Falkenburg, Planning Intern (GIS/Mapping, Editing) City of Milwaukee Redevelopment Authority David Misky, Assistant Executive Director - Secretary Department of Public Works Mike Loughran, Special Projects Manager Walker’s Point Kristin Bennett, Bicycle Coordinator Strategic Action Plan Historic Preservation Carlen Hatala, Historic Preservation Principal Researcher iii Plan Advisory Group Sean Kiebzak, Arts@Large Juli Kaufmann, Fix Development Dan Adams, Harbor District Initiative Joe Klein, HKS/Junior House Dean Amhaus, Milwaukee Water Council Anthony A. LaCroix Nick & JoAnne Anton, La Perla Scott Luber, Independence First Samer Asad, Envy Nightclub Barry Mandel, The Mandel Group Luis “Tony” Baez, El Centro Hispano Megan & Tyler Mason, Wayward Kitchen Tricia M. Beckwith, Wangard Partners Robert Monnat, The Mandel Group Kristin Bennett, Bike Ped Coordinator Cristina Morales Brigette Breitenbach, Company B Lorna Mueller, The Realty Company, LLC Mike Brenner, Brenner Brewing Co.
    [Show full text]
  • 1 Introduction
    1 Field-control, phase-transitions, and life’s emergence 2 3 4 Gargi Mitra-Delmotte 1* and A.N. Mitra 2* 5 6 7 139 Cite de l’Ocean, Montgaillard, St.Denis 97400, REUNION. 8 e.mail : [email protected] 9 10 2Emeritius Professor, Department of Physics, Delhi University, INDIA; 244 Tagore Park, 11 Delhi 110009, INDIA; 12 e.mail : [email protected] 13 14 15 16 17 18 19 *Correspondence: 20 Gargi Mitra-Delmotte 1 21 e.mail : [email protected] 22 23 A.N. Mitra 2 24 e.mail : [email protected] 25 26 27 28 29 30 31 32 33 34 35 Number of words: ~11748 (without Abstract, references, tables, and figure legends) 36 7 figures (plus two figures in supplementary information files). 37 38 39 40 41 42 43 44 45 46 47 Abstract 48 49 Critical-like characteristics in open living systems at each organizational level (from bio- 50 molecules to ecosystems) indicate that non-equilibrium phase-transitions into absorbing 51 states lead to self-organized states comprising autonomous components. Also Langton’s 52 hypothesis of the spontaneous emergence of computation in the vicinity of a critical 53 phase-transition, points to the importance of conservative redistribution rules, threshold, 54 meta-stability, and so on. But extrapolating these features to the origins of life, brings up 55 a paradox: how could simple organics-- lacking the ‘soft matter’ response properties of 56 today’s complex bio-molecules--have dissipated energy from primordial reactions 57 (eventually reducing CO 2) in a controlled manner for their ‘ordering’? Nevertheless, a 58 causal link of life’s macroscopic irreversible dynamics to the microscopic reversible laws 59 of statistical mechanics is indicated via the ‘functional-takeover’ of a soft magnetic 60 scaffold by organics (c.f.
    [Show full text]
  • Sculptor Nina Slobodinskaya (1898-1984)
    1 de 2 SCULPTOR NINA SLOBODINSKAYA (1898-1984). LIFE AND SEARCH OF CREATIVE BOUNDARIES IN THE SOVIET EPOCH Anastasia GNEZDILOVA Dipòsit legal: Gi. 2081-2016 http://hdl.handle.net/10803/334701 http://creativecommons.org/licenses/by/4.0/deed.ca Aquesta obra està subjecta a una llicència Creative Commons Reconeixement Esta obra está bajo una licencia Creative Commons Reconocimiento This work is licensed under a Creative Commons Attribution licence TESI DOCTORAL Sculptor Nina Slobodinskaya (1898 -1984) Life and Search of Creative Boundaries in the Soviet Epoch Anastasia Gnezdilova 2015 TESI DOCTORAL Sculptor Nina Slobodinskaya (1898-1984) Life and Search of Creative Boundaries in the Soviet Epoch Anastasia Gnezdilova 2015 Programa de doctorat: Ciències humanes I de la cultura Dirigida per: Dra. Maria-Josep Balsach i Peig Memòria presentada per optar al títol de doctora per la Universitat de Girona 1 2 Acknowledgments First of all I would like to thank my scientific tutor Maria-Josep Balsach I Peig, who inspired and encouraged me to work on subject which truly interested me, but I did not dare considering to work on it, although it was most actual, despite all seeming difficulties. Her invaluable support and wise and unfailing guiadance throughthout all work periods were crucial as returned hope and belief in proper forces in moments of despair and finally to bring my study to a conclusion. My research would not be realized without constant sacrifices, enormous patience, encouragement and understanding, moral support, good advices, and faith in me of all my family: my husband Daniel, my parents Andrey and Tamara, my ount Liubov, my children Iaroslav and Maria, my parents-in-law Francesc and Maria –Antonia, and my sister-in-law Silvia.
    [Show full text]
  • Gazeta Winter 2016
    Chaim Goldberg, Purim Parade, 1993, oil painting on canvas Volume 23, No. 1 Gazeta Winter 2016 A quarterly publication of the American Association for Polish-Jewish Studies and Taube Foundation for Jewish Life & Culture Editorial & Design: Fay Bussgang, Julian Bussgang, Shana Penn, Vera Hannush, Alice Lawrence, Maayan Stanton, LaserCom Design. Front Cover Photo: Chaim Goldberg; Back Cover Photo: Esther Nisenthal Krinitz J.D. Kirszenbaum, Self-portrait, c. 1925, oil on canvas TABLE OF CONTENTS Message from Irene Pipes ............................................................................................... 1 Message from Tad Taube and Shana Penn ................................................................... 2 RESEARCH PROJECT The Holocaust in the Eyes of Polish Youth By Dr. Jolanta Ambrosewicz-Jacobs .................................................................................. 3 ART AS FAMILY LEGACY A Daughter Returns with Memories in Art By Bernice Steinhardt .......................................................................................................... 7 Resurrection of a Painter: “From Staszów to Paris, via Weimar, Berlin and Rio de Janeiro” By Nathan Diament ........................................................................................................... 12 Creating a New Museum in Kazimierz By Shalom Goldberg ......................................................................................................... 16 CONFERENCES, SPRING/SUMMER PROGRAMS, AND FESTIVALS Conference on Launch of Volume
    [Show full text]
  • Comparison of the Results from Six Calorimeters in the Determination of the Thermokinetics of a Model Reaction Wassila Benaissa, Douglas Carson
    Comparison of the results from six calorimeters in the determination of the thermokinetics of a model reaction Wassila Benaissa, Douglas Carson To cite this version: Wassila Benaissa, Douglas Carson. Comparison of the results from six calorimeters in the determina- tion of the thermokinetics of a model reaction. AIChE Spring Meeting 2011 & 7. Global Congress on Process Safety (GCPS), Mar 2011, Chicago, United States. pp.NC. ineris-00976225 HAL Id: ineris-00976225 https://hal-ineris.archives-ouvertes.fr/ineris-00976225 Submitted on 9 Apr 2014 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Comparison of the Results from Six Calorimeters in the Determination of the Thermokinetics of a Model Reaction Wassila BENAISSA INERIS Parc Technologique Alata BP 2, F-60550 Verneuil-en-Halatte [email protected] Douglas CARSON INERIS Keywords: calorimeter, thermal runway, kinetics Abstract This paper deals with the comparison of experimental results from several types of commercially available calorimeters: a screening calorimeter (DSC), a Calvet calorimeter (C80), a reaction calorimeter (RC1), and various pseudo-adiabatic calorimeters (VSP 2, ARSST, and Phi-Tec 1). One exothermic reaction was selected as a case study: the esterification of acetic anhydride by methanol, a system which has been well studied in the literature.
    [Show full text]
  • Six Canonical Projects by Rem Koolhaas
    5 Six Canonical Projects by Rem Koolhaas has been part of the international avant-garde since the nineteen-seventies and has been named the Pritzker Rem Koolhaas Architecture Prize for the year 2000. This book, which builds on six canonical projects, traces the discursive practice analyse behind the design methods used by Koolhaas and his office + OMA. It uncovers recurring key themes—such as wall, void, tur montage, trajectory, infrastructure, and shape—that have tek structured this design discourse over the span of Koolhaas’s Essays on the History of Ideas oeuvre. The book moves beyond the six core pieces, as well: It explores how these identified thematic design principles archi manifest in other works by Koolhaas as both practical re- Ingrid Böck applications and further elaborations. In addition to Koolhaas’s individual genius, these textual and material layers are accounted for shaping the very context of his work’s relevance. By comparing the design principles with relevant concepts from the architectural Zeitgeist in which OMA has operated, the study moves beyond its specific subject—Rem Koolhaas—and provides novel insight into the broader history of architectural ideas. Ingrid Böck is a researcher at the Institute of Architectural Theory, Art History and Cultural Studies at the Graz Ingrid Böck University of Technology, Austria. “Despite the prominence and notoriety of Rem Koolhaas … there is not a single piece of scholarly writing coming close to the … length, to the intensity, or to the methodological rigor found in the manuscript
    [Show full text]
  • The Use of Accelerating Rate Calorimetry (ARC) for the Study of the Thermal Reactions of Li-Ion Battery Electrolyte Solutions J.S
    Journal of Power Sources 119–121 (2003) 794–798 The use of accelerating rate calorimetry (ARC) for the study of the thermal reactions of Li-ion battery electrolyte solutions J.S. Gnanaraja, E. Zinigrada, L. Asrafa, H.E. Gottlieba, M. Sprechera, D. Aurbacha,*, M. Schmidtb aDepartment of Chemistry, Bar-Ilan University, Ramat-Gan 52900, Israel bMerck KGaA, D-64293 Darmstadt, Germany Abstract The thermal stability of 1M LiPF6, LiClO4, LiN(SO2CF2CF3)2 (LiBETI) and LiPF3(CF2CF3)3 (LiFAP) solutions in mixtures of ethylene carbonate, diethyl carbonate and dimethyl carbonate in the temperature range 40–350 8C was studied by ARC and DSC. NMR was used to analyze the reaction products at different reaction stages. The least thermally stable are LiClO4 solutions. LiPF3(CF2CF3)3 solutions showed higher thermal stability than LiPF6 solutions. The highest thermal stability was found for LiN(SO2CF2CF3)2 solutions. Studies by DSC and pressure measurements during ARC experiments with LiPF6 and LiFAP solutions detected an endothermic reaction, which occurs before a number of exothermic reactions as the temperature increases. Fluoride ions are formed and react with the alkyl carbonate molecules both as bases and as nucleophiles. # 2003 Elsevier Science B.V. All rights reserved. Keywords: Accelerating rate calorimetry (ARC); Differential scanning calorimetry (DSC); Thermal stability; Alkyl carbonate solutions 1. Introduction 2. Experimental Accelerating rate calorimetry (ARC) is an important One molar LiPF6, LiClO4, LiN(SO2CF2CF3)2 and method for studying the thermal behavior of materials LiPF3(CF2CF3)3 solutions in mixture of ethylene carbonate [1,2]. LiPF6 solutions in alkyl carbonates are widely used (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC) in commercial Li-ion batteries in spite of their relatively low (2:1:2 v/v/v) were obtained from Merck KGaA (highly pure, thermal stability.
    [Show full text]
  • Principal Facts of the Earth's Magnetism and Methods Of
    • * Class Book « % 9 DEPARTMENT OF COMMERCE U. S. COAST AND GEODETIC SURVEY E. LESTER JONES, Superintendent PRINCIPAL FACTS OF THE EARTH’S MAGNETISM AND METHODS OF DETERMIN¬ ING THE TRUE MERIDIAN AND THE MAGNETIC DECLINATION [Reprinted from United States Magnetic Declination Tables and Isogonic Charts for 1902] [Reprinted from edition of 1914] WASHINGTON GOVERNMENT PRINTING OFFICE 1919 ( COAST AND GEODETIC SURVEY OFFICE. DEPARTMENT OF COMMERCE U. S. COAST AND GEODETIC SURVEY »» E. LESTER JONES, Superintendent PRINCIPAL FACTS OF THE EARTH’S MAGNETISM AND METHODS OF DETERMIN¬ ING THE TRUE MERIDIAN AND THE MAGNETIC DECLINATION [Reprinted from United States Magnetic Declination Tables and Isogonic Charts for 1902 ] i [ Reprinted from edition of 1914] WASHINGTON GOVERNMENT PRINTING OFFICE 4 n; «f B. AUG 29 1913 ft • • * C c J 4 CONTENTS. Page. Preface. 7 Definitions. 9 Principal Facts Relating to the Earth’s Magnetism. Early History of the Compass. Discovery of the Lodestone. n Discovery of Polarity of Lodestone. iz Introduction of the Compass..... 15 Improvement of the Compass by Petrius Peregrinus. 16 Improvement of the Compass by Flavio Gioja. 20 Derivation of the word Compass. 21 Voyages of Discovery. 21 Compass Charts. 21 Birth of the Science of Terrestrial Magnetism. Discovery of the Magnetic Declination at Sea. 22 Discovery of the Magnetic Declination on Land. 25 Early Methods for Determining the Magnetic Declination and the Earliest Values on Land. 26 Discovery of the Magnetic Inclination. 30 The Earth, a Great Magnet. Gilbert’s “ De Magnete ”.'. 34 The Variations of the Earth’s Magnetism. Discovery of Secular Change of Magnetic Declination. 38 Characteristics of the Secular Change.
    [Show full text]
  • Chemical Reactions Involve Energy Changes
    Page 1 of 6 KEY CONCEPT Chemical reactions involve energy changes. BEFORE, you learned NOW, you will learn • Bonds are broken and made • About the energy in chemical during chemical reactions bonds between atoms • Mass is conserved in all • Why some chemical reactions chemical reactions release energy • Chemical reactions are • Why some chemical reactions represented by balanced absorb energy chemical equations VOCABULARY EXPLORE Energy Changes bond energy p. 86 How can you identify a transfer of energy? exothermic reaction p. 87 endothermic reaction p. 87 PROCEDURE MATERIALS photosynthesis p. 90 • graduated cylinder 1 Pour 50 ml of hot tap water into the cup • hot tap water and place the thermometer in the cup. • plastic cup 2 Wait 30 seconds, then record the • thermometer temperature of the water. • stopwatch • plastic spoon 3 Measure 5 tsp of Epsom salts. Add the Epsom salts to the beaker and immedi- • Epsom salts ately record the temperature while stirring the contents of the cup. 4 Continue to record the temperature every 30 seconds for 2 minutes. WHAT DO YOU THINK? • What happened to the temperature after you added the Epsom salts? • What do you think caused this change to occur? Chemical reactions release or absorb energy. COMBINATION NOTES Chemical reactions involve breaking bonds in reactants and forming Use combination notes new bonds in products. Breaking bonds requires energy, and forming to organize information on how chemical reactions bonds releases energy. The energy associated with bonds is called bond absorb or release energy. energy. What happens to this energy during a chemical reaction? Chemists have determined the bond energy for bonds between atoms.
    [Show full text]