Preview Chemistry in Context by American Chemical Society Bradley D Fahlman (2017) Preview Chemistry in Context by American Chemical Society Bradley D Fahlman (2017) Preview Chemistry in Context by American Chemical Society Bradley D Fahlman (2017) Preview Chemistry in Context by American Chemical Society Bradley D Fahlman (2017) Preview Chemistry in Context by American Chemical Society Bradley D Fahlman (2017)
CHEMISTRY in CONTEXT Ninth Edition Applying Chemistry to Society A Project of the American Chemical Society Chemistry in Context Applying Chemistry to Society ® A Project of the American Chemical Society Ninth Edition Chemistry in Context Applying Chemistry to Society Bradley D Fahlman Central Michigan University Kathleen L Purvis-Roberts Claremont McKenna, Pitzer, and Scripps Colleges John S Kirk Carthage College Anne K Bentley Lewis & Clark College Patrick L Daubenmire Loyola University Chicago Jamie P Ellis Ithaca College Michael T Mury All Saints Academy ® A Project of the American Chemical Society CHEMISTRY IN CONTEXT: APPLYING CHEMISTRY TO SOCIETY, NINTH EDITION Published by McGraw-Hill Education, Penn Plaza, New York, NY 10121 Copyright © 2018 by the American Chemical Society All rights reserved Printed in the United States of America Previous editions © 2015, 2012, and 2009 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 consent of McGraw-Hill Education, including, but not limited to, in any network or other electronic storage or transmission, or broadcast for distance learning Some ancillaries, including electronic and print components, may not be available to customers outside the United States This book is printed on acid-free paper LWI/LWI 21 20 19 18 17 ISBN 978-1-259-63814-5 MHID 1-259-63814-6 Chief Product Officer, SVP Products & Markets: G Scott Virkler Vice President, General Manager, Products & Markets: Marty Lange Vice President, Content Design & Delivery: Betsy Whalen Managing Director: Thomas Timp Director of Chemistry: David Spurgeon, Ph.D Director, Product Development: Rose Koos Product Developer: Jodi Rhomberg Marketing Manager: Matthew Garcia Market Development Manager: Tamara Hodge Director of Digital Content: Shirley Hino, Ph.D Digital Product Developer: Joan Weber Digital Product Anaylst: Patrick Diller Director, Content Design & Delivery: Linda Avenarius Program Manager: Lora Neyens Content Project Managers: Sherry Kane / Tammy Juran Buyer: Laura M Fuller Designer: Tara McDermott Content Licensing Specialists: Carrie Burger / Lori Slattery Cover Image: © Ingram Publishing/SuperStock (landfill); © Image Source/Getty Images (smoke stacks); © Johan Swanepoel/Shutterstock (finger print); © Echo/Getty Images (store clerk); © William Leaman/Alamy (spider web); © payless images/123RF (recycle bin); â McGraw-Hill Higher Education (periodic table) Compositor: Aptarađ, Inc Typeface: 10/12 STIX Mathjax Main Printer: LSC Communications All credits appearing on page are considered to be an extension of the copyright page Library of Congress Cataloging-in-Publication Data Names: Fahlman, Bradley D American Chemical Society Title: Chemistry in context : applying chemistry to society Description: Ninth edition / Bradley D Fahlman, Central Michigan University [and six others] New York, NY : McGraw-Hill Education, [2018] Previous edition: chemistry in context : applying chemistry to society / Catherine H Middlecamp (New York, NY : McGraw-Hill Education, 2015) “A project of the American Chemical Society.” Identifiers: LCCN 2016044871 ISBN 9781259638145 (alk paper) ISBN 1259638146 (alk paper) Subjects: LCSH: Biochemistry Environmental chemistry Geochemistry Classification: LCC QD415 C482 2018 | DDC 540—dc23 LC record available at https://lccn.loc.gov/2016044871 The Internet addresses listed in the text were accurate at the time of publication The inclusion of a website does not indicate an endorsement by the authors or McGraw-Hill Education, and McGrawHill Education does not guarantee the accuracy of the information presented at these sites Logo applies to the text stock only mheducation.com/highered Brief Contents 1 Portable Electronics: The Periodic Table in the Palm of Your Hand 2 The Air We Breathe 38 3 Radiation from the Sun 78 4 Climate Change 118 5 Energy from Combustion 170 6 Energy from Alternative Sources 228 7 Energy Storage 270 8 Water Everywhere: A Most Precious Resource 306 9 The World of Polymers and Plastics 358 10 Brewing and Chewing 398 11 Nutrition 428 12 Health & Medicine 482 13 Genes and Life 522 14 Who Killed Dr Thompson? A Forensic Mystery 554 Appendices 1 Measure for Measure: Metric Prefixes, Conversion Factors, and Constants A-1 2 The Power of Exponents A-2 3 Clearing the Logjam A-3 4 Answers to Your Turn Questions A-5 5 Answers to Selected End-of-Chapter Questions Indicated in Blue in the Text Glossary Index A-50 G-1 I-1 v Contents Preface xiii Chapter Portable Electronics: The Periodic Table in the Palm of Your Hand 1.2 Atomic Legos—Atoms as Building Blocks for Matter 1.3 Compounding the Complexity— From Elements to Compounds 1.4 What Makes Atoms Tick? Atomic Structure 11 1.5 One-Touch Surfing: How Do Touchscreens Work? 12 1.7 Chemical Rock-’n-Roll: How Do We Obtain Pure Metals from Complex Rocks? 14 16 1.8 Your Cell Phone Started with a Day at the Beach: From Sand to Silicon 18 1.9 More Fun at the Beach: From Sand to Glass 24 1.10 From Cradle to Grave: The Life Cycle of a Cell Phone 28 1.11 Howdy Neighbor, May We Borrow a Few Metals? The Importance of Recycling and Protecting Our Supply Chains 32 Conclusions 34 Learning Outcomes 34 Questions 35 Chapter The Air We Breathe 38 2.2 Defining the Invisible: What Is Air? 40 2.3 You Are What You Breathe 42 2.4 What Else Is in the Air? 44 2.1 Why Do We Breathe? 46 2.7 A Chemical Meet & Greet— Naming Molecular Compounds 47 1.1 What’s the Matter with Materials? A Survey of the Periodic Table 1.6 A Look at the Elements in Their Natural States 2.6 I Can “See” You! Visualizing the Particles in the Air 39 2.5 Home Sweet Home: The Troposphere 45 2.8 The Dangerous Few: A Look at Air Pollutants 49 2.9 Are You Feeling Lucky? Assessing the Risk of Air Pollutants 51 2.10 Is It Safe to Leave My House? Air Quality Monitoring and Reporting 54 2.11 The Origin of Pollutants: Who’s to Blame? 57 2.12 More Oxygen, Please: The Effect of Combustion on Air Quality 60 2.13 Air Pollutants: Direct Sources 62 2.14 Ozone: A Secondary Pollutant 66 2.15 Are We Really Safe from Polluted Air by Staying Indoors? 69 2.16 Is There a Sustainable Way Forward? 71 Conclusions 72 Learning Outcomes 73 Questions 73 Chapter Radiation from the Sun 78 3.2 The Personalities of Radiation 84 3.1 Dissecting the Sun: The Electromagnetic Spectrum 79 3.3 The ABCs of Ultraviolet Radiation 86 3.4 The Biological Effects of Ultraviolet Radiation 87 3.5 The Atmosphere as Natural Protection 91 3.6 Counting Molecules: How Can We Measure the Ozone Concentration? 93 3.7 How Does Ozone Decompose in UV Light? 94 3.8 How Safe Is Our Protective Ozone Layer? 98 © Thinkstock/Index Stock RF vii viii Contents 3.9 Chemistry to the Rescue Detriment? Human Roles in the Destruction of the Ozone Layer 5.7 How Efficient Is a Power Plant? 187 101 3.10 Where Do We Go from Here: Can the Ozone Hole Be Restored? 105 3.11 How Do Sunscreens Work? 109 Conclusions 113 Learning Outcomes 113 Questions 114 Chapter Climate Change 4.1 Carbon, Carbon Everywhere! Source: NASA/Scientific Visualization Studio/Goddard Space Flight Center 118 120 5.8 Power from Ancient Plants: Coal 190 5.9 From Steam Engines to Sports Cars: The Shift from Coal to Oil 195 5.10 Squeezing Oil from Rock: How Long Can This Continue? 196 5.11 Natural Gas: A “Clean” Fossil Fuel? 198 5.12 Cracking the Whip: How Do We Obtain Useful Petroleum Products from Crude Oil? 200 5.13 What’s in Gasoline? 204 5.14 New Uses for an Old Fuel 207 4.2 Where Did All the Carbon Atoms Go? 123 4.3 Quantifying Carbon— First Stop: Mass 5.15 From Brewery to Fuel Tank: Ethanol 208 125 4.4 Quantifying Carbon—Next Stop: Molecules and Moles 5.16 From Deep Fryer to Fuel Tank: Biofuels 212 127 4.5 Why Does It Matter Where Carbon Atoms End Up? 5.17 Are Biofuels Really Sustainable? 216 130 4.6 Warming by Greenhouse Gases: Good, Bad, or a Little of Both? 132 4.7 How Do You Recognize a “Greenhouse Gas”? 133 4.8 How Do Greenhouse Gases Work? Chapter 138 Energy from Alternative Sources 228 4.9 How Can We Learn from Our Past? 142 4.10 Can We Predict the Future? 148 4.11 A Look at Our Future World 153 4.12 Action Plans to Prevent Future Global Catastrophes— Who and How? 158 Conclusions 221 Learning Outcomes 221 Questions 222 6.1 From Nuclear Energy to Bombs: The Splitting of Atomic Nuclei 230 6.2 Harnessing a Nuclear Fission Reaction: How Nuclear Power Plants Produce Electricity 235 6.3 What Is Radioactivity? 239 6.4 How Long Do Substances Remain Radioactive? 242 6.5 What Are the Risks of Nuclear Power? 245 6.6 Is There a Future for Nuclear Power? 249 172 6.7 Solar Power: Electricity from the Sun 252 5.2 Burn, Baby! Burn! The Process of Combustion 174 6.8 Solar Energy: Electronic “Pinball” Inside a Crystal 255 5.3 What Is “Energy”? 176 5.4 How Hot Is “Hot”? Measuring Energy Changes 177 6.9 Beyond Solar: Electricity from Other Renewable (Sustainable) Sources 261 Conclusions 164 Learning Outcomes 165 Questions 166 Chapter Energy from Combustion 5.1 Fossil Fuels: A Prehistoric Fill-Up at the Gas Station 170 5.5 Hyperactive Fuels: How Is Energy Released during Combustion? 182 5.6 Fossil Fuels and Electricity 185 Conclusions 266 Learning Outcomes 266 Questions 267 Contents Chapter Energy Storage 7.1 How Does a Battery Work? 7.2 Ohm, Sweet Ohm! 270 273 275 7.3 Batteries, Batteries Everywhere! 277 7.4 (Almost) Endless Power-on-the-Go: Rechargeable Batteries 7.5 Lead–Acid: The World’s Most Widely Used (and Heaviest!) Rechargeable Battery 7.6 Vehicles Powered by Electricity 7.7 Storage Wars: Supercapacitors vs Batteries 278 281 282 285 287 7.9 Fuel Cells: The Basics 290 7.10 Hydrogen for Fuel Cell Vehicles 294 Conclusions 301 Learning Outcomes 301 Questions 302 Chapter 306 309 8.2 The Unique Composition of Water 310 8.3 The Key Role of Hydrogen Bonding 313 8.4 Where, Oh Where Is All the Water? 8.5 Help! There Is Something in My Water Chapter The World of Polymers and Plastics 358 9.2 Polymers: Long, Long Chains 360 9.3 Adding Up the Monomers 362 9.4 Got Polyethylene? 364 9.5 The “Big Six”: Theme and Variations 367 373 9.7 From Proteins to Stockings: Polyamides 377 9.8 Dealing with Our Solid Waste: The Four Rs 379 9.9 Recycling Plastics: The Bigger Picture 383 9.10 From Plants to Plastics 389 9.11 A New “Normal”? 391 Conclusions 393 Learning Outcomes 394 Questions 394 Brewing and Chewing 10.1 What’s in a Mouthful? The Science of Taste 398 400 10.2 How Does Smell Affect Taste? 401 403 10.4 The Science of Recipes 404 316 10.5 Kitchen Instrumentation: Flames, Pans, and Water 406 320 10.6 Cooking in a Vacuum: Not Just for Astronauts! 411 324 8.7 A Deeper Look at Solutes 327 334 8.9 Heartburn? Tums® to the Rescue: Acid/Base Neutralization! 338 8.10 Quantifying Acidity/Basicity: The pH Scale 340 8.11 Acid’s Effect on Water 341 8.12 Treating Our Water 345 © Bignai/Shutterstock.com Chapter 10 10.3 The Kitchen Laboratory 8.6 How Much Is OK? Quantifying Water Quality 8.8 Corrosive and Caustic: The Properties and Impacts of Acids and Bases Conclusions 352 Learning Outcomes 352 Questions 353 9.6 Cross-Linking Monomers 7.11 My Battery Died—Now What? 298 8.1 Solids and Liquids and Gases, Oh My! 8.13 Water Solutions for Global Challenges 348 9.1 Polymers Here, There, and Everywhere 359 7.8 Higher MPGs with Less Emissions: Gasoline-Electric Hybrid Vehicles Water Everywhere: A Most Precious Resource ix 10.7 Microwave Cooking: Fast and Easy 413 10.8 Cooking with Chemistry: No-Heat Food Preparation 414 10.9 How Can I Tell When My Food Is Ready? 416 10.10 Exploiting the Three States of Matter in Our Kitchen 419 10.11 The Baker’s and Brewer’s Friend: Fermentation 423 10.12 From Moonshine to Sophisticated Liqueurs: Distillation 423 Portable Electronics: The Periodic Table in the Palm of Your Hand Figure 1.14 Figure 1.15 Technicians work inside a clean room at Sanan Optoelectronics Co., Ltd in Tianjin, China Computer processing chips placed onto a single fingertip 23 © Charle Avice/age fotostock/Alamy Stock Photo © Bradley D Fahlman (a) (b) (c) (d) (e) (f) (g) Figure 1.16 A comparative perspective of an integrated circuit The scale bar in each image roughly corresponds to the: (a) diameter of a cloud water droplet; (b) diameter of mold spores; (c) diameter of a human hair fiber; (d) diameter of common beach sand; (e) thickness of a human cornea; (f) diameter of a pinhead; (g) diameter of a pupil © Bradley D Fahlman (Jonathon Clapham, Department of Chemistry and Biochemistry, Central Michigan University and Phillip Oshel, Department of Biology, Central Michigan University) 24 Chapter a computer chip to reveal the variety of complex micro- and nano-sized architectures Indeed, the chip that runs a computer or a cell phone is truly an engineering marvel that would not be possible without the numerous chemical reactions that occur during chip processing Perhaps most astonishing, all of this is possible through the conversion of ordinary sand into silicon! | 1.9 More Fun at the Beach: From Sand to Glass So far, we have talked about the metals and semiconductors used in a portable electronic device However, those of us who have peered through the cracked screens on our cell phones are very familiar with another component in most portable electronic devices—glass You might be surprised to learn that sand is not only used to fabricate high-purity silicon, but also the crystal-clear transparent glass that we interact with on mobile devices Your Turn 1.17 Scientific Practices Interactions Light-Matter Using a laser pointer, predict and then determine whether light will be transmitted, reflected, or absorbed during its contact with a/an: a c e g Figure 1.17 Light microscope image of sand taken from Big Talbot Island, Florida, illustrating the individual crystals of silica © Sabrina Pintus/Getty Images RF Glass window Plasma TV screen Asphalt road Cotton shirt b LCD screen d Concrete sidewalk f Ceramic plate When you consider the front surface of your mobile device, what kind of properties should it have? Qualities that you may look for include transparency, scratch resistance, and shatter resistance To find a material with these properties, scientists and engineers have taken a page from nature One of the largest components of Earth’s crust is silica (i.e., silicon dioxide, SiO2 (s)), which is found in many different forms These forms vary by composition and structure, with each having different properties At the atomic level, silica consists of repeating linkages between silicon and oxygen in a dense, spider web-like structure There are some naturally formed silicon dioxide structures with very well-ordered structures at the atomic level This ordered structure is called a crystal Pure crystallized silicon dioxide is known as quartz, a clear and colorless mineral that is the primary component of sand (Figure 1.17) When small amounts of other elements are present in the crystal, it can give the mineral some color For example, the yellow color of citrine and the purple color of amethyst are from different forms of iron that are present in trace amounts within the silicon dioxide crystal (Figure 1.18) In contrast to well-ordered quartz, the structure of glass is disordered on the atomic level with a random array of silicon and oxygen linkages throughout the solid (Figure 1.19) What a tangled web we weave with glass! Disordered materials such as this are called amorphous solids Although relatively brittle compared to crystalline silicon dioxide, glass has the ability to be molten in a fluid-like state and worked into different shapes for various purposes Silica glass is made from heating ordinary sand to a high enough temperature to melt it (Figure 1.20), then cooling the liquid until it hardens to a glass A variety of Portable Electronics: The Periodic Table in the Palm of Your Hand (a) 25 (b) Figure 1.18 Photos of (a) citrine, and (b) amethyst—forms of quartz with iron impurities that give it varying colors (a): © TinaImages/Shutterstock.com; (b): © Alexander Hoffmann/Shutterstock.com Figure 1.20 (a) (b) Figure 1.19 Molecular representations of (a) crystalline quartz, and (b) amorphous glass (a-b): © McGraw-Hill Education additives may be mixed with the silica raw material before melting, which can give the resulting glass a wide range of properties For instance, the PyrexTM glass used for cookware not only contains silicon and oxygen atoms, but also boron (B) and traces of other metals such as sodium (Na), aluminum (Al), and potassium (K) The addition of these elements to glass greatly improves its thermal properties by limiting the extent of expansion at high temperatures, or contraction at low temperatures, to reduce its likelihood of cracking As you can imagine, temperatures required for melting pure silicon dioxide are very high—in excess of 1700 °C! Adding a type of material called flux lowers the melting point by breaking some of the linkages between silicon and oxygen atoms Common fluxes are salts such as sodium carbonate (Na2CO3), calcium carbonate (CaCO3), and magnesium carbonate (MgCO3) In addition to lowering the melting temperature of the glass, these additives make the molten glass less viscous and easier to work into the intricate shapes that you often see in glass artwork As you saw in the previous activity, when light shines onto a piece of silicon dioxide, whether it is crystalline quartz or amorphous glass, it mostly passes straight through the material This means that the material is transparent Whenever there are Molten sand being poured from a ceramic crucible Source: Photo Courtesy of the University of Wisconsin-Stout Archives and Area Research Center The lower the viscosity of a liquid, the easier it will flow when being poured from a vessel For instance, water has much less viscosity than molasses or honey, and will therefore flow much easier 26 Chapter Did You Know? Mendeleev’s experience in the family glass works fueled his interest in the elements and his search for a periodic arrangement Figure 1.21 Figure 1.22 Stained glass windows of St Chappelle in Paris, France Photo showing the formation of a Prince Rupert’s drop from quickly cooling a drop of molten glass, demonstrating its high mechanical strength © John Kirk © Bradley D Fahlman A crystal of smoky quartz © Albert Russ/Shutterstock.com Figure 1.23 Photo of a broken windshield, showing the retainment of smaller glass fragments by the plastic film coating © Esa Hiltula/Alamy RF differences in the structure or the composition at the microscopic level, the path of light through the material is altered, potentially making it opaque Pure crystalline quartz, having the same structure throughout, certainly is transparent However, if there are imperfections or impurities present, such as in smoky quartz and milky quartz, the mineral becomes opaque Although amorphous glass has a variation in its atomic-level structure distributed randomly throughout the entire material, it will still allow light to pass through the material giving it transparency Of course, over the past several millennia, glassworkers have discovered quite a few additives that give glass some color or make the glass opaque Beautiful examples of this are the stained glass windows commonly found in Europe’s many cathedrals, such as those of St Chappelle in Paris, France, shown in Figure 1.21 Some of this stained glass is colored red by the inclusion of nanoparticles of gold! If you ever roughhoused in your family’s living room when you were young or played softball close to parked cars, you probably know that glass can be quite fragile How could this material be useful for a device that has the potential to be dropped and broken? Much research has gone into improving the strength and scratch resistance of glass In the 17th century, it was discovered that quickly cooling a drop of molten glass in cold water results in a hardened drop that could withstand a hammer blow (Figure 1.22) However, a small amount of force to the long tail of these so-called Prince Rupert’s drops would cause the entire glass piece to s hatter explosively into small fragments The strength of the material comes from the quick hardening of the outer portion of the glass, freezing it into place while the inside of the drop is still cooling As we’ll discuss later, cooling down an object tends to shrink its size Because the outer surface of the drop is locked in place, there is a lot of internal stress in the drop as the interior of the glass tries to pull the outer surface inward Many types of tempered glass have been heat-treated to behave very similarly to these drops Since heat-strengthened glass tends to shatter into very small pieces when broken, it is often laminated or coated with a thin layer of plastic For instance, when an automobile windshield is broken, the pieces are quite small and tend to stick together, thus resulting in fewer severe injuries from large pieces of glass (Figure 1.23) Portable Electronics: The Periodic Table in the Palm of Your Hand 27 4-Ton elephant x 100,000 elephants! 10 GPa Figure 1.24 Illustration of the pressure felt by each foot of a bottom elephant, if 100,000 four-ton elephants were stacked on top of each other—certainly, an impossible task! © Bradley D Fahlman In addition to heat treatment, chemical treatments can also strengthen glass This is precisely the technique that has been used by Corning Corp to fabricate Gorilla GlassTM—the tough scratch-resistant glass that is used in a wide variety of mobile device screens, including cell phones, tablets, and laptop computers This glass is theoretically able to withstand a pressure of 10 GPa, which is equivalent to the pressure exerted by a stack of 100,000 elephants (Figure 1.24)! This incredible strength is achieved by submerging the glass into a bath of molten potassium nitrate (KNO3) As shown in Figure 1.25, potassium ions from the bath will replace some of the smaller sodium ions close to the surface of the glass This results in the same types of stresses on the surface of the glass as found in Prince Rupert’s drops Gorilla GlassTM screens are scratch/shatter-resistant when dropped, but are not scratch/shatter-proof Corning and other companies are actively researching the next generation of materials for mobile device screens These materials include not just amorphous materials like glass, but crystalline materials, too Sapphire “glass” is one of the potential The unit GPa (gigapascals) refers to × 109 Pa—1,000,000 times greater than kPa and 1,000 times greater than MPa KNO3 BATH Glass Surface Glass O Si Al K+ (radius: 1.33 A)̊ Na+ (radius: 0.97 A)̊ Figure 1.25 Structural schematic of Gorilla GlassTM, in which sodium ions are replaced with larger potassium ions 28 The density of a material refers to its mass/volume ratio Lightweight materials such as aluminum and plastics that are used for portable electronics will have a relatively low density, whereas building materials such as steel, concrete, and others used for bridges and buildings, generally have comparatively high densities Chapter replacements Sapphire is a natural gemstone that is harder than quartz In fact, s apphire is the second-hardest material known after diamond Sapphire is composed of aluminum oxide, the same substance discussed in Section 1.7 As a comparison, the crystal structure of aluminum oxide is three times harder than Gorilla GlassTM Synthetic sapphire requires heating fine aluminum oxide powder at extremely high temperatures—as high as 1800 °C! The crystal growth process is very slow, taking more than two weeks to grow a single large crystal Once formed, it is cut into its final size and shape by a diamond saw or a laser While sapphire is extremely hard, it is denser than glass This means that for the same size and thickness of m aterial, sapphire will weigh more The weight of sapphire is 67% heavier than an equivalent size piece of glass The production of synthetic sapphire is also more costly and slower than glass; however, further development of production methods are bringing the cost down Sapphire is already used for surfaces that see a lot of wear-and-tear such as checkout scanners, airplane windows, and high-end watches With improvements in production, we may be seeing many more sapphire screens on mobile devices in the very near future Your Turn 1.18 Scientific Practices Density a An unknown metal was found to have a mass of 424 g By water displacement, the volume of the solid was determined to be 47.8 mL Identify the metal based on these known densities: gold, 19.3 g/mL; copper, 8.86 g/mL; bronze, 9.87 g/mL. b Why is there an increase in the use of aluminum-based frames in automobiles in place of iron/steel-based frames? | 1.10 From Cradle to Grave: The Life Cycle of a Cell Phone With the increase of active cell phones in the world outpacing the growth of the human population, it is essential that we understand the environmental impacts that their production, use, and disposal have on our planet The expression cradle-to-grave is an approach to analyzing the life cycle of an item, starting with the raw materials from which it came and ending with its ultimate disposal Think of items that we take for granted each day such as batteries, plastic water bottles, T-shirts, cleaning supplies, running shoes, and, of course, cell phones—a nything that you buy and eventually discard Where did the item come from? What will happen to the item when you are finished with it? More than ever, individuals, communities, and corporations are recognizing the importance of asking these types of questions Cradle-to-grave means thinking about every step in the process, leading to its final disposal As a simple illustration, let’s follow the plastic packaging that cradled your shiny new cell phone when it was proudly unveiled The raw material for this packaging is petroleum Accordingly, the “cradle” of this plastic product most likely was crude oil somewhere on our planet—for example, the oil fields of Alberta, Canada At the refinery, a range of processes were carried out on the crude oil to convert fractions into the compound styrene The styrene molecules (C8H8) were linked together (polymerized) to form polystyrene, which is also commonly used for StyrofoamTM coffee cups, CD/ DVD “jewel” cases, and many other commercial products The polystyrene packaging was then packaged and transported from the refinery in Canada or the United States (burning jet or diesel fuels—other refinery products) to the final assembly plant in China or Taiwan However, what was the fate of this packaging material after you removed the new cell phone? This is not really a cradle-to-grave scenario, but rather cradle-to-your- Portable Electronics: The Periodic Table in the Palm of Your Hand trash—definitely several steps short of any graveyard The term grave describes wherever an item eventually ends up Unlike other types of plastics that may be easily recycled, polystyrene is not accepted in most plastic recycling bins As a result, this type of plastic is the principle component of landfills, urban litter, and marine debris where it begins a presumed 1000-year cycle of slow decomposition into carbon dioxide and water, as well as potentially toxic substances Cradle-to-a-grave-somewhere-on-the-planet is a poorly planned scenario for plastic packaging If the polystyrene waste instead was to serve as the starting material for a new product, or creatively reused in its native state, we then would have a more sustainable situation Cradle-to-cradle, a term that emerged in the 1970s, refers to a responsible use of materials in which the end of the life cycle of one item dovetails with the beginning of the life cycle of another, so that everything is reused rather than disposed of as waste When considering the most responsible end-use of a product, one should consider the three pillars of sustainability: ■ ■ ■ 29 In Chapter 9, we will examine the main classes of plastics, their applications, and a variety of recycle-and-reuse scenarios Environmental—pollution prevention, natural resource use Social—better quality of life for all members of society Economic—fair distribution and efficient allocation of resources As you would expect, the life cycle of a cell phone—an assemblage of many different types of materials from varying parts of the world—would be much more complex than that of its packaging materials Among the materials comprising a cell phone, 40% are metals, 40% are plastics, and 20% are ceramics and glass Properties of metals such as electrical and thermal conductivity, durability, and malleability (ability to be bent into complex shapes) are exploited for the circuit board, battery, and touch-sensitive screen In contrast, the lightweight, inexpensive, and moldable properties of plastics are well suited for the protective case and LCD screen Ceramics and glass exhibit brittleness and are electrically insulating Glass is most often used for the outer screen to protect the underlying LCD display, whereas ceramics are used within the circuit board, speaker, and antenna So, how much energy is required to fabricate such a complex design? After all, electronic devices are getting smaller/thinner and more efficient (Figure 1.26), which means less energy will be required to produce them, correct? In fact, it’s just the opposite, 32" CRT TV The term energy is a transferable property of matter While energy may be transferred from one object to another, it cannot be created or destroyed $51.50 42" Plasma TV $41.13 XBox 360 $40.24 $28.21 Desktop PC 32" LED TV $12.88 Digital photoframe $10.34 Laptop PC iPad The circuit board is the “brain” of the phone, controlling multiple functionalities The circuit board consists of analog-to-digital (and vice versa) chips, flash memory and ROM (storage) chips, and the microprocessor that controls the keyboard and screen functions Common metals employed in the circuit board include copper, gold, lead, nickel, zinc, beryllium, tantalum, and others in trace amounts $8.31 $1.36 Samsung Galaxy s6 $0.49 Apple iPhone 6s plus $0.56 $0 $10 $20 $30 $40 $50 $60 Figure 1.26 Comparison of annual operating costs for various electronic devices Annual costs are based on an average U.S residential electricity rate of $0.12/kWh 30 Chapter with their production from raw materials accounting for more than 90% of the energy consumed over their lifetime! This is not the case with low-tech products such as light bulbs, vacuum cleaners, and ovens that consume much more energy over their lifetimes than was spent for their fabrication Automobiles used to be in the same “low-tech” category, controlled by analog devices; however, microprocessors now monitor and control every aspect of modern vehicles from the fuel injection system to tailpipe emissions The increased energy consumption during the production of high-tech devices is primarily because: More diverse materials are needed, which requires greater costs for mining and purification, as well as the manufacturing of ceramics and plastics ■ Microprocessors (computer chips) originate from the energy-intensive conversion of sand into ultra-high-purity silicon, and must go through hundreds of complex steps required to fabricate the integrated circuits ■ Complex devices require many hours of design with teams of people using multiple high-speed computers that run continuously for 24 hours a day, days a week ■ The unit “kgCO2e” (kg of equivalent CO2) refers to the relative emissions of greenhouse gases (carbon dioxide, methane (CH4), and/or nitrous oxide (N2O)) per unit of fuel that is consumed The unit MJ is a megajoule, or × 106 joules As you will see in Chapter 5, a joule is the standard unit of energy, and corresponds to the energy required to lift a small apple (with a mass of 100 grams) vertically through one meter of air A megajoule (MJ) corresponds to the kinetic energy of a one-tonne (1000 kg) vehicle moving at 100 mph (160 km/h) While it is quite easy to determine how much energy an electronic device consumes during its operation, it is very difficult to calculate the energy used in its fabrication For instance, a new cell phone begins its production many years before it is released, in the hands of engineers who plan out its features and design the complex architecture and computer chips that it will employ It’s hard to estimate how much energy this initiative will consume, because it involves the electricity to power the buildings and laboratories used for research and development Administrators and members of the sales force also use electricity in their offices and consume fossil fuels during their extensive travel. Overlooking these pre-manufacturing activities simplifies the situation somewhat, but we still have the problem of globalization That is, the silicon employed for the computer chips may be purified in Michigan, the circuit board built in California, the lithium for the battery mined and purified in Chile, and the plastics synthesized in China Some variability in these locations depends on the company’s supply chain, which will vary dramatically between electronics companies The amount of energy required to mine lithium metal in South America would be very different than what is required in Canada Hence, this makes a general life-cycle analysis very difficult to predict with any level of accuracy without knowing more information about the manufacturing practices of each materials supplier As an example of how complex the situation is for a single company, Apple has 18 final assembly facilities and over 200 suppliers of the raw materials and components needed for their product lines More companies are becoming transparent about the environmental footprint of their products For instance, Apple reports that the iPad is responsible for 220 kgCO2e over its lifetime, with 75% of those emissions from manufacturing, 19% from consumer use, 5% from transport, and 1% from recycling In contrast, the iPhone with its smaller energy footprint is reported to release 80 kgCO2e, with 84% generated from production, 10% from consumer use, 5% from transport, and 1% from recycling However, there is no way to accurately include information about the energy consumption of the supply chain companies Furthermore, the environmental standards of countries differ greatly, which often results in outsourcing to countries where sustainability is not considered as a top priority. Based on the environmental emissions data above, an iPhone consumes a total of 152 kWh of electricity over its lifetime, which corresponds to 546 MJ of energy (464 MJ from production alone) To put this in perspective, a gallon of gasoline contains 131 MJ of energy In other words, the energy contained in four gallons of gasoline (and the emissions that were released from its combustion) was needed to fabricate a single iPhone While this may not seem too significant, bear in mind that there are currently over billion cell phones in use on the planet, with approximately billion new phones sold every year Further, there are significantly more tablets, Portable Electronics: The Periodic Table in the Palm of Your Hand 31 laptops, and other electronic devices that each require more energy to produce than cell phones In fact, a 27″ iMac computer requires approximately 3,500 MJ of electrical energy (or 480 kgCO2e) to fabricate—7.5 times more energy than an iPhone Folding in consumer use, transportation, and recycling, the iMac will consume a total of 7,200 MJ of electrical energy (980 kgCO2e) over its lifetime! The environmental impact numbers we have discussed thus far only deal with the direct fabrication, use, and recycling of electronic devices However, the full life cycle of a device also includes many other energy-intensive activities that are needed to extract, refine, and transport the raw materials from various parts of the world to the central fabrication facility (Figure 1.27) How much energy does it take to extract lithium metal from an ore in Chile? It depends on how difficult the ore is to reach, and what specific techniques the company uses to break apart the ore, extract the metal, and then refine/purify the metal once it is removed The same may be said about other components of the phone such as the outer screen Whereas Samsung doesn’t expend much energy in attaching the glass to the case in its final assembly Metals Polymers (plastics) Organic chemicals and solvents Ceramics Glasses Gases High temperatures High-energy light Electricity Metal ores Sand Limestone Fossil fuels (electricity & plastics fabrication) Water High temperatures CO2, NOx, SOx emissions waste from mining CO2, NOx, SOx emissions Gaseous, liquid, and solid waste Cell phone fabrication Material extraction & processing Use by consumers Electricity used by cell phones, routers, base stations, switching stations, administrative offices Discarded packaging Electromagnetic radiation from cell phones & towers Recycling and/or disposal Electricity and energy for disassembly Electricity and energy for materials recycling (chemical and/or thermal treatment) Solid waste in landfills Particulate matter (PM), CO2, Volatile organic compounds (VOCs) Emissions from incineration Figure 1.27 The life cycle of a cell phone The years spent for its design and marketing are not included 32 Chapter plant, how much energy did the glass manufacturer consume to convert sand into a high-strength glass, and then ship large crates of the material to China for final assembly? The answers to these questions are not easily obtainable, and illustrate just how complicated it is to determine the full environmental impact of a high-tech device in our globalized society Your Turn 1.19 Scientific Practices Energy Requirements Other than charging, what are some other energy requirements of your cell phone? Your Turn 1.20 Scientific Practices Smartphone Usage Considering how energy-intensive it is to fabricate cell phones, you think increasing smartphone usage could cause a decrease in the overall energy consumption in our planet? Explain. | 1.11 Howdy Neighbor, May We Borrow a Few Did You Know? In 2015, Apple reported the recovery of over 61 million pounds of steel, aluminum, and other metals from old Mac computers Of this total, over 2,200 pounds of gold was recovered, which corresponds to around $40 million! Metals? The Importance of Recycling and Protecting Our Supply Chains Although approximately billion new cell phones are purchased each year, over 90% of these phones will either collect dust at home or be sent to landfills after their owners grow tired of them A sparse 3% will be recycled, while 7% will be re-sold However, did you know that each cell phone contains about 300 mg of silver and 30 mg of gold, which is 50 times more concentrated than its ore in a mine? In fact, the gold and silver used in cell phones sold this year alone are estimated to be worth more than $2.5 billion! Who would have thought our urban landfills are virtual goldmines? Needless to say, the process of recycling electronics needs to be further developed, because the recycling of metals from electronics— while not easy—requires significantly less energy than mining and purifying the metal from its ore Some companies are starting to focus on this initiative, such as the Brussels-based company Umicore Even automakers are developing in-house recycling programs for their electronic devices and batteries Your Turn 1.21 You Decide Recycling An aluminum mining company has claimed that it is less expensive and energy intensive to extract Al from ore instead of recycling aluminum cans Consider the costs and energy sources involved in both processes, and decide whether this claim is valid Perhaps the most difficult step in electronics recycling is to remove the metals from the device itself This process consists of boiling the circuit boards in solvents to remove the plastics and then leaching out the metals with strong acids However, if one is not careful, groundwater could become contaminated with heavy metals and organic waste, possibly contributing to an increase of cancers and other life-threatening illnesses in the surrounding communities Unfortunately, these recycling practices are often outsourced to developing countries where environmental regulations are not established and proper safety precautions are not adopted for workers Portable Electronics: The Periodic Table in the Palm of Your Hand IIA Group Period IA VB VIB 10 VIIB VIIIB VIIIB VIIIB 11 IB 12 IIB 13 IIIA 14 IVA 15 VA 16 VIA 17 18 VIIA VIIIA Hydrogen 1.00794 Lithium 6.941 11 Na 19 Be Beryllium 9.012182 12 13 Magnesium Aluminum Al 24.3050 26.9815386 20 21 22 23 Calcium 40.078 Scandium 44.955912 Titanium 47.867 Vanadium 50.9415 37 38 39 Rubidium 85.4678 Strontium 87.62 Yttrium 88.90585 55 56 K Potassium 39.0983 Rb Cs Ca Sr Ba Cesium 87 Barium 137.327 Sc Francium (223) Ra Radium (226) 24 Cr Chromium 51.9961 25 Mn Manganese 54.938045 26 27 Fe Co Iron 55.845 Cobalt 58.933195 28 Ni Nickel 58.6934 29 Cu Copper 63.546 30 Zn Zinc 65.39 31 Ga Gallium 69.723 41 42 43 44 45 46 47 48 Niobium 92.90638 Molybdenum Technetium Ruthenium Rhodium 102.90550 Palladium 106.42 Silver 107.8682 Cadmium 112.411 72 73 74 75 76 77 78 79 80 81 Hafnium 178.49 Tantalum 180.94788 Tungsten 183.84 Rhenium 186.207 Osmium 190.23 Platinum 195.084 196.966569 Mercury 200.59 Thallium 204.3833 104 105 106 107 108 109 110 111 112 Actinides Rutherfordium Dubnium (262) Seaborgium Bohrium (264) Hassium (277) Meitnerium Darmstadtium Roentgenium Copernicium 57 58 59 60 61 62 63 64 65 66 67 Praseodymium Neodymium Promethium Samarium 150.36 Europium 151.964 Gadolinium Terbium 158.92535 Dysprosium Holmium 164.93032 93 94 95 96 97 98 99 Neptunium Plutonium (244) Americium Berkelium (247) Californium Einsteinium 57–71 Lanthanides 89–103 Lanthanum 138.90547 Zr Hf Rf (261) Ce Cerium 140.116 Nb Ta Db Pr 140.90765 Mo 95.94 W Sg (266) Nd 144.242 89 90 91 92 Actinium (227) Thorium 232.03806 231.03588 Protactinium Uranium 238.02891 Ac Actinides V 40 La Lanthanides Ti Zirconium 91.224 Y 88 Fr B Boron 10.811 Mg Sodium He Helium 4.002602 Li 132.9054519 IVB H 22.98976928 IIIB 33 Th Pa U Tc (97.9072) Re Bh Pm (145) Np (237) Ru 101.07 Os Hs Sm Pu Rh Ir Iridium 192.217 Mt (268) Eu Am (243) Pd Pt Ds (281) Gd 157.25 Cm Curium (247) Ag Au Gold Rg (280) Tb Bk Cd Hg Cn (285) Dy 162.500 Cf (251) 49 In Indium 114.818 Tl 113 Uut Ununtrium (284) Ho Es (252) C Carbon 12.0107 14 Si Silicon 28.0855 N Nitrogen 14.0067 15 P Phosphorus 30.973762 O Oxygen 15.9994 16 S Sulfur 32.065 F Fluorine 18.9984032 17 Cl Chlorine 35.453 32 33 34 Germanium Arsenic 74.92160 Selenium 78.96 50 51 52 53 Antimony 121.760 Tellurium 127.60 Iodine 126.90447 83 84 85 Ge 72.61 Sn Tin 118.710 82 Pb Lead 207.2 As Sb Bi Se Te Po 35 Br Bromine 79.904 I At Ne Neon 20.1797 18 Ar Argon 39.948 36 Kr Krypton 83.798 54 Xe Xenon 131.293 86 Rn Bismuth 208.98040 Polonium (209) 114 115 116 117 118 Ununquadium Ununpentium Ununhexium Ununseptium Ununoctium 69 70 71 Thulium 168.93421 Ytterbium 173.054 Lutetium 174.9668 100 101 102 103 Fermium (257) Mendelevium Noblelium (259) Lawrencium Fl (289) 68 Er Erbium 167.259 Fm Uup (288) Tm Md (258) Lv (293) Yb No Astatine (210) 10 Uus (294) Radon (222) Uuo (294) Lu Lr (262) Figure 1.28 Periodic table of the elements The positions of the rare earth metals are highlighted in blue Production in Metric Tons Rare Earth Oxide Equivalent Other than the precious metals of silver, gold, and platinum, another class of metals that are increasingly important for our society are the “rare earth” metals (Figure 1.28) These elements are employed for many applications that we rely on every day such as vehicle catalytic converters and fluorescent lighting, as well as memory chips, rechargeable batteries, magnets, and speakers found inside cell phones and portable electronic devices The military also uses a variety of rare earths for night-vision goggles, advanced weaponry, GPS equipment, batteries, and advanced electronics China is the world’s leading producer of rare earth metals (Figure 1.29), but is also an increasing consumer for the finished electronic products Over 90% of the 150,000 120,000 90,000 Other 60,000 China 30,000 1950 USA 1965 1980 1995 2010 Figure 1.29 Illustration of the dominance of China in the mining of the rare earth metals 34 Chapter world’s supply of rare earth elements are exported from China, who also holds more than 50% of the world’s total reserve of these metals Indeed, advanced technology can be thought of as a double-edged sword for a society We are fortunate to enjoy the benefits of faster, lighter, and more powerful portable devices As a result of this technology, we are more accessible in our b usinesses, more quickly connected with our social circles, and better able to navigate while away from computers However, we also open ourselves up to a heightened level of risk associated with the availability of our source materials Once a society progresses beyond antiquated devices and fully adopts new technology, there is no turning back But what if a key raw material needed to fabricate our cell phones and electronic devices is no longer available? This may arise from a number of causes such as natural disasters, political unrest, energy restrictions, or trade barriers Whatever the cause, how we manage to continue the production of electronic devices needed for our businesses and personal lives? And what if these materials are also essential for national security? One answer might be to find alternative raw materials, known as earthabundant materials, that would have similar functionalities While this could be possible for some substances, for the rare earths this is usually not an option Although research and development efforts are underway around the world, there are no suitable alternatives for a number of rare earth elements It is even more important that we continue to develop alternative technologies that either require smaller amounts of rare earth metals, or none at all For instance, consumers in the United States are transitioning from fluorescent lighting, which uses a relatively large amount of rare earths, to more energy-efficient light-emitting diodes (LEDs) Although the components responsible for light generation in LEDs, known as phosphors, may also be composed of rare earth oxides, these elements are present in a lesser amount than is required for fluorescent lights Conclusions It is hard for many to imagine life without the use of a smartphone or portable electronic device The latest weather report, our favorite music, and the answers to life’s most difficult questions are now only a touch away Without the role of chemistry, we would not be able to acquire the elements and compounds that comprise our modern electronic devices Indeed, the chemical transformations of rocks and minerals into pure Si and metals are required for virtually all aspects of our modern lifestyles However, there are limited global reserves for some elements used in portable electronics, such as the rare earths As the world scurries to find more sources for the rare earths—even looking on the ocean floors—we can more easily acquire these and other low-abundant materials that have already been mined This can be realized by simply developing low-cost (and environmentally friendly) recycling protocols for the used electronic devices sitting in our drawers at home or those discarded in urban landfills The next chapter will describe how our manufacturing and end-use practices for electronics affect the very air we breathe We will move beyond the clean room, where a trace of oxygen will cause problems with computer chip fabrication, to the real world that needs oxygen in order to sustain human life Learning Outcomes The numbers in parentheses indicate the sections within the chapter where these outcomes were discussed Having studied this chapter, you should now be able to: ■ classify and compare the states of matter (1.1) ■ describe how manipulation of matter influences its properties (1.1) ■ define chemistry (1.1) ■ ■ describe the connection between macroscopic properties and the particulate composition of matter (1.2, 1.3, 1.4) classify metals, nonmetals, and metalloids in terms of electrical conductivity, indicate their location on the periodic table, and predict some components of a portable electronic device they would be most suited for (1.1) Portable Electronics: The Periodic Table in the Palm of Your Hand ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ select an appropriate unit of measurement based on the scale of the object (1.2) convert among different units (1.2) describe the differences between atoms, molecules, elements, and compounds, and give examples for each (1.2, 1.3) describe the differences between ionic and molecular compounds, and calculate the atomic percentages of various compounds (1.3) distinguish between mixtures and pure substances, and categorize matter into these two classifications (1.1, 1.6) define mixtures, and classify them as either heterogeneous or homogeneous (1.1, 1.6) explain the physical and chemical transformations involved in the fabrication and recycling of portable electronic devices (throughout the chapter) illustrate the structure of an atom, including the neutron, electron, and proton and compare the relative locations, charges, and masses of the subatomic particles (1.4) evaluate how the subatomic particles govern the identity of the elements and their placement in the periodic table (1.4) define electrical and thermal conductivity and describe their relationship (1.5) describe and diagram how a touchscreen works (1.5) describe the composition of Earth’s crust, in terms of relative concentrations of its components (1.6) determine the correct number of significant figures for measured and calculated values (1.6) ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ 35 describe how metals and silicon are separated from ore (1.7) define oxidation and reduction, and illustrate how atoms become positively and negatively charged ions (1.7) write the formulas of simple ionic compounds (1.7) convert numbers between decimal form and scientific notation (1.8) measure, calculate, and compare different densities of materials (1.9) explain why transparency is important for electronic displays (1.9) predict and compare the way light interacts with different types of matter (1.9) explain how we can alter materials to change or enhance properties such as durability or transparency (1.9) identify and select materials based on their properties (throughout the chapter) define energy and describe its role in the fabrication, use, and recycling of portable electronic devices (1.10) define the three pillars of sustainability, and relate these principles to the fabrication, use, and recycling of portable electronic devices (1.10) distinguish cradle-to-grave from cradle-to-cradle, and predict some environmental, economic, and social impacts of both philosophies (1.10) identify sources and possible alternatives for lowabundant materials used in portable electronics (1.11) Questions The end-of-chapter questions are grouped in three ways: ■ Emphasizing Essentials questions give you the opportunity to practice fundamental skills They are similar to the Skill Building exercises in the chapter ■ Concentrating on Concepts questions are more difficult and may relate to societal issues They are similar to the Scientific Practices activities in the chapter ■ Exploring Extensions questions challenge you to go beyond the information presented in the text They are similar to the You Decide activities in the chapter Emphasizing Essentials In these diagrams, two different types of atoms are represented by color and size Characterize each sample as an element, a compound, or a mixture Explain your reasoning Appendix contains the answers to questions with numbers in blue (a) (b) (c) (d) Questions marked with this icon relate to green chemistry 36 Chapter From the solids, liquids, or gases that are present in your favorite room or office, list three homogeneous mixtures and three heterogeneous mixtures Also, provide the names and symbols or chemical formulas of any elements or compounds, respectively Convert the diameter of the period at the end of this sentence into nanometers. Express each of these numbers in scientific notation a 1500 m, the distance of a foot race b 0.0000000000958 m, the distance between O and H atoms in a water molecule c 0.0000075 m, the diameter of a red blood cell Express m in terms of cm, μm, and nm Use proper scientific notation in your answers Consider this portion of the periodic table and the groups shaded on it a What is the group number for each shaded region? b Name the elements that make up each group c Give a general characteristic of the elements in each of these groups Consider the following blank periodic table a Locate the region of the periodic table in which metals are found b Common metals include iron, magnesium, aluminum, sodium, potassium, and silver Give the chemical symbol for each c Give the name and chemical symbol for five nonmetals (elements that are not in your shaded region) Classify each of these substances as an element, a compound, or a mixture a a sample of “laughing gas” (dinitrogen monoxide, also called nitrous oxide) b steam coming from a pan of boiling water c a bar of deodorant soap d a sample of copper e a cup of mayonnaise f the helium filling a balloon Draw the structures and describe the properties for two allotropes of sulfur How are these fabricated? 10 Provide the number of protons, neutrons, and electrons for an aluminum atom with a mass number of 27 How these numbers change once an Al atom is oxidized to form an Al3+ ion? Provide the numbers of protons, neutrons, and electrons for a S2– ion with a mass number of 32 11 Classify each of the following compounds as molecular or ionic a KBr b P2O5 c SO3 d SrCl2 e XeF4 12 Calculate the atomic percentages for each of the following compounds a HfO2 b BeCl2 c Ti(OH)4 d FeO e SiO2 f B(OH)3 13 For the following molecules, list the number and type of atoms that each contain a CO2 b H2S c NO2 d SiO2 14 The density of a mystery solid is 1.14 g/cm3 Will this float or sink in pure water? Explain 15 What are the oxidation states of the metals in the following compounds? a CuO b Al2O3 c FeCl3 d Mn2O7 Concentrating on Concepts 16 In the text, we illustrated the 12N purity of silicon in terms of colored tennis balls Provide illustrations of your own for 9N and 12N purities 17 The processor chips in portable and desktop electronics are composed of tiny switches, known as transistors What are the smallest dimensions of the transistors used in current processors? Relate these dimensions in terms of nm and km 18 What is meant by “Moore’s Law” and is this still valid? 19 Describe how aluminum metal is isolated from its natural ore, as well as the processes involved in its purification 20 The use of sapphire for the screens of portable electronic devices will soon become prevalent Compare the physical properties, molecular structures, and fabrication techniques for glass and sapphire 21 Glass is generally thought to be an electrical insulator However, is it possible to fabricate “conductive glass”? Explain 22 Using a molecular perspective, describe the formation of Prince Rupert’s drops and their violent implosion when the droplet tail is fractured 23 Describe some components of your cell phone that are in units of cm, mm, μm and nm 24 List three metals that are currently used in cell phones that have a natural abundance in Earth’s crust of < 50 ppm Portable Electronics: The Periodic Table in the Palm of Your Hand 25 Can you fabricate high-purity silicon for use in portable electronic devices from plentiful sea sand? Explain 26 List some waste products generated from the fabrication of high-purity silicon 27 Critique the accuracy of the following statement: “As cell phones become smaller in size and less expensive, their impact on the environment will increase.” 28 Evaluate the current portable electronics industry in terms of the three pillars of sustainability For each pillar, provide a letter-grade rating and suggest three possibilities for improvement Exploring Extensions 29 The crystal structures of many gemstones are based on SiO2 and Al2O3 frameworks Considering that pure silica and alumina are white solids, describe the origin of the diverse colors exhibited by gemstones 30 It can be said that “impurities affect the physical properties of most crystalline solids.” Explain 31 “Smart glass” that becomes opaque with a flip of a switch is now being used in businesses and hotel rooms across the world Describe how glass can transition from transparent to opaque with the passage of electrical current 32 Describe some procedures that have been used to recycle the metals found in cell phones 33 Cell phone companies have advertised “superior toxic substance removal” from their products Which elements have been removed and where were these located within cell phones? Find a precedent for soil and water pollution that arose from the improper recycling of electronic devices How could these situations have been prevented? 35 Provide a cradle-to-cradle strategy for the recycling of processor “chips” found in portable electronics 36 Draw a flowchart that illustrates the reactions required to convert SiO2 sand into high-purity silicon What happens to the waste products that are generated in each step? How sustainable is this process? 37 In this chapter, we described the reactions required to convert SiO2 sand into high-purity Si Compare and contrast the Czochralski (CZ) and float zone processes to fabricate long cylinders of the high-purity silicon, known as ingots Which technique is more energy intensive? How are these Si ingots used in the fabrication of processor chips? 37 38 Using Internet resources, perform a life-cycle analysis for your cell phone Try to be as detailed as possible for two scenarios: cradle-to-grave and cradle-to-cradle. 39 Describe some environmental impacts that are involved during the design, research and development, and marketing phases of cell phones before their ultimate production and release to consumers? 40 Compare and contrast the steps, associated costs, and energy use required to extract aluminum from ore vs recycling, and rate these practices based on their overall efficiency and sustainability 41 Consider the image below that shows the increasing global demand for rare earth metals Calculate the percentage increases in demand for China, Japan/NE Asia, USA, and the rest of the world between 2012 and 2016 Due to rising prices of the rare earths and limited global supplies, more countries are evaluating recycling programs to extract and reuse these elements from existing devices What devices contain rare-earth metals? Based on the number of these devices sold annually, their average lifetimes, and assuming that 100% of available devices are recycled with 100% recovery of the metals, could the U.S meet its current demand through recycling efforts alone? Explain 110,000 100,000 2012 90,000 2016 80,000 Metric tons 70,000 60,000 50,000 40,000 30,000 20,000 10,000 China Japan & NE Asia USA Rest of world .. .Chemistry in Context Applying Chemistry to Society ® A Project of the American Chemical Society Ninth Edition Chemistry in Context Applying Chemistry to Society Bradley D Fahlman Central... Cataloging -in- Publication Data Names: Fahlman, Bradley D American Chemical Society Title: Chemistry in context : applying chemistry to society Description: Ninth edition / Bradley D Fahlman, Central Michigan... regarding the role of equilibria on the health of our bodies and the processes involved in modern drug design ■ Chapter 13 (genetics): additional information and references are added regarding