1 / 96

How to Use This Presentation

How to Use This Presentation. To View the presentation as a slideshow with effects select “View” on the menu bar and click on “Slide Show.” To advance through the presentation, click the right-arrow key or the space bar.

karacarroll
Télécharger la présentation

How to Use This Presentation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. How to Use This Presentation • To View the presentation as a slideshow with effects select “View” on the menu bar and click on “Slide Show.” • To advance through the presentation, click the right-arrow key or the space bar. • From the resources slide, click on any resource to see a presentation for that resource. • From the Chapter menu screen click on any lesson to go directly to that lesson’s presentation. • You may exit the slide show at any time by pressing the Esc key.

  2. Resources Chapter Presentation Visual Concepts Transparencies Standardized Test Prep Brain Food Video Quiz

  3. Chapter 7 Resources and Energy Table of Contents Section 1 Mineral Resources Section 2 Nonrenewable Energy Section 3 Renewable Energy Section 4 Resources and Conservation

  4. Chapter 7 Section 1 Mineral Resources Objectives • Explainwhat ores are and how they form. • Identifyfour uses for mineral resources • Summarizetwo ways humans obtain mineral resources

  5. Chapter 7 Section 1 Mineral Resources Mineral Resources • Mineral resources can be either metals, such as gold, U, silver, Ag, and aluminum, Al, or nonmetals, such as sulfur, S, and quartz, SiO2. • Metals can be identified by their shiny surfaces, as good conductors of heat and electricity, and they tend to bend easily when in thin sheets. • Most nonmetals have a dull surface and are poor conductors of heat and electricity.

  6. Chapter 7 Section 1 Mineral Resources Ores oresa natural material whose concentration of economically valuable minerals is high enough for the material to be mined profitably Metallic minerals such as gold, silver, and copper, Cu, are called native elements and can exist in Earth’s crust as nuggets of pure metals. Most other minerals in Earth’s crust are compounds of two or more elements.

  7. Chapter 7 Section 1 Mineral Resources Ores, continued Ores Formed by Cooling Magma • Some ores, such as chromium, Cr; and nickel, Ni, form as the magma cools and the dense metallic minerals sink. • As the minerals sink, layers of these minerals accumulate at the bottom of the magma chamber to form ore deposits. Ores Formed by Contact Metamorphism lodea mineral deposit within a rock formation.

  8. Chapter 7 Section 1 Mineral Resources Ores, continued Ores Formed by Contact Metamorphism,continued • Heat and chemical reactions with hot fluids from the magma can change the composition of the surrounding rock. This process is called. • Some ores, such as copper, Cu; and zinc, Zn, form by contact metamorphism. • Contact metamorphism also occurs when hot fluids called hydrothermal solutions move through small cracks in a large mass of rock. • When the minerals from the surrounding rock dissolve into the hydrothermal solution, new minerals will precipitate from the solution and form narrow zones of rocks called veins.

  9. Chapter 7 Section 1 Mineral Resources Ores, continued Ores Formed by Moving Water placer deposita deposit that contains a valuable mineral that has been concentrated by mechanical action • The movement of water helps to form ore deposits. • Tiny fragments of native elements, such as gold, Au, are released from rock as it breaks down by weathering. • Streams carry the fragments until the currents become too weak to carry these dense metals, which collect in placer deposits.

  10. Chapter 7 Section 1 Mineral Resources Uses of Mineral Resources gemstonesa mineral, rock, or organic material that can be used as jewelry or an ornament when it is cut and polished • Metallic ores are sources of valuable minerals and elements, like gold, Au, platinum, Pt, and silver, Ag. • Some nonmetallic minerals display extraordinary brilliance and color when they are specially cut for jewelry. • Other nonmetallic minerals, such as calcite and gypsum, are used as building materials.

  11. Chapter 7 Section 1 Mineral Resources Mineral Exploration and Mining • During mineral exploration, people search for mineral deposits by studying local geology. • Exploration teams also collect and test rock samples to determine whether the rock contains enough metals to make a mine profitable. • Airplanes that carry special equipment are used to measure and identify patterns in magnetism, gravity, radioactivity, and rock color.

  12. Chapter 7 Section 1 Mineral Resources Mineral Exploration and Mining, continued Subsurface Mining • Subsurface mining mines for minerals located below Earth’s surface Surface Mining • Surface mining strips overlying rock material to reveal mineral deposits that are located close to Earth’s surface. Placer Mining • Placer mining scoop up and separate the sediment from placer deposits to search for minerals. Undersea Mining • Nodules are lumps of minerals on the deep ocean floor. However, because of their location, these deposits are difficult to mine.

  13. Chapter 7 Section 1 Mineral Resources The Formation of Ores and Placer Deposits The diagram below shows how ores form in placer deposits.

  14. Chapter 7 Section 1 Mineral Resources Reading check Explain the relationship between carrying capacity and the amount of matter and energy in an ecosystem.

  15. Chapter 7 Section 1 Mineral Resources Reading check, continued Explain the relationship between carrying capacity and the amount of matter and energy in an ecosystem. The amount of matter and energy in an ecosystem can supply a population of a given size. This maximum population is the carrying capacity of the ecosystem.

  16. Chapter 7 Section 1 Mineral Resources Comparing Metals, Nonmetals, and Metalloids

  17. Chapter 7 Section 2 Nonrenewable Energy Objectives • Explainwhy coal is a fossil fuel. • Describehow petroleum and natural gas form and how they are removed from Earth. • Summarizethe processes of nuclear fission and nuclear fusion. • Explainhow nuclear fission generates electricity

  18. Chapter 7 Section 2 Nonrenewable Energy Nonrenewable Energy nonrenewable resource a resource that forms at a rate that is much slower than the rate at which it is consumed FossilFuels fossilfuela nonrenewable energy resource that formed from the remains of organisms that lived long ago; examples include oil, coal, and natural gas • Much of the energy humans use every day comes from the burning of the hydrocarbons that make up fossil fuels. • When hydrocarbons are burned, the breaking of chemical bonds releases energy as heat and light.

  19. Chapter 7 Section 2 Nonrenewable Energy Fossil Fuels Formation of Coal • Coal is the most commonly burned fossil fuel, formed during a complex process called carbonization. • Carbonization occurs when partially decomposed plant materials is buried in swamp mud and becomes peat. • As bacteria consume some of the peat and release the gases methane, CH4, and carbon dioxide, CO2, the contents of peat gradually change until mainly carbon remains. • Peat remains if conditions are not optimal for carbonization. Peat may be used as an energy source.

  20. Chapter 7 Section 2 Nonrenewable Energy Types of Coal The diagram below shows the different types of coal.

  21. Chapter 7 Section 2 Nonrenewable Energy Fossil Fuels, continued Types of Coal Deposits • The partial decomposition of plant remains forms a brownish-black material called peat. • Peat is buried by other sediment. As heat and pressure increase peat becomes lignite. Lignite is also called brown coal. • Increased temperature and pressure compacts the lignite and forms bituminous coal. Bituminous coal is made of 80% carbon. • Anthracite, the hardest form of coal, is produced when bituminous coal is under high temperatures and pressures. Anthracite coal is made of 90% carbon.

  22. Chapter 7 Section 2 Nonrenewable Energy Fossil Fuels, continued Formation of Petroleum and Natural Gas • Petroleum and natural gas are mixtures of hydrocarbons. • These fossil fuels formed when heat and pressure caused chemical changes to the remains of microorganisms and plants. Petroleum and Natural Gas Deposits • Petroleum and natural gas are very important sources of energy for transportation, farming, and many other industries. • They are mined from permeable sedimentary rocks. • Petroleum accumulates beneath cap rock and fill the space to form an oil reservoir. Natural gas rises above petroleum, because it is less dense than both oil and water.

  23. Chapter 7 Section 2 Nonrenewable Energy Oil Traps The diagram below shows how oil becomes trapped under cap rock.

  24. Chapter 7 Section 2 Nonrenewable Energy Fossil Fuels, continued Oil Traps • When a well is drilled into an oil reservoir, the petroleum and natural gas often flow to the surface. • After the pressure of the overlying rock is removed, fluids rise up and out through the well.

  25. Chapter 7 Section 2 Nonrenewable Energy Fossil-Fuel Supplies • Fossil fuels, like minerals, are one of the main sources of energy, but are also nonrenewable resources. • Crude oil, or unrefined petroleum, is also used in the production of plastics, synthetic fabrics and rubber, medicines, waxes, chemical fertilizers, detergents, shampoos, and many other products. • Coal is the most abundant fossil fuel in the world. Two-thirds of the known deposits of coal occur in the United States, Russia, and China. • Oil shale is a relatively abundant material that contains petroleum. But the cost of mining oil from shale is far greater than the present cost of recovering oil from other sedimentary rocks.

  26. Chapter 7 Section 2 Nonrenewable Energy Reading check What is cap rock?

  27. Chapter 7 Section 2 Nonrenewable Energy Reading check, continued What is cap rock? Cap rock is a layer of impermeable rock at the top of an oil or natural gas-bearing formation through which fluids cannot flow.

  28. Chapter 7 Section 2 Nonrenewable Energy Nuclear Energy • The energy that is produced from nuclear reactions is called nuclear energy. • Scientists discovered that atoms had smaller fundamental parts. • These parts could be split by creating nuclear reactions with nuclear technologies.

  29. Chapter 7 Section 2 Nonrenewable Energy Nuclear Energy, continued Nuclear Fission nuclear fissionthe process by which the nucleus of a heavy atom splits into two or more fragments; the process releases neutrons and energy • When the nucleus splits, it releases additional neutrons as well as energy. • The newly released neutrons begin a chain reaction by striking nearby nuclei, which causes those nuclei to split and release more neutrons and more energy. • If left uncontrolled, a fission reaction will escalate quickly and may result in an explosion. Controlled reactions produce heat that can be used to generate electricity.

  30. Chapter 7 Section 2 Nonrenewable Energy Reading check What causes a chain reaction during nuclear fission?

  31. Chapter 7 Section 2 Nonrenewable Energy Reading check, continued What causes a chain reaction during nuclear fission? As neutrons strike neighboring nuclei, the nuclei split and release additional neutrons that strike other nuclei and cause the chain to continue.

  32. Chapter 7 Section 2 Nonrenewable Energy Nuclear Energy, continued How Fission Generates Electricity • A nuclear reactor is a specialized equipment in which controlled nuclear fission is carried out. • Currently, uranium-235, or 235U, is the only naturally occurring element used for nuclear fission. • This ore is mined and processed into fuel pellets with high 235U content. • These uranium-enriched pellets are placed into rods to make fuel rods. Bundles of these fuel rods are then bombarded by neutrons to induce a nuclear reaction.

  33. Chapter 7 Section 2 Nonrenewable Energy Nuclear Energy, continued How Fission Generates Electricity, continued • The resulting chain reaction from nuclear fission causes the fuel rods to become very hot. • Water is pumped around the fuel rods to absorb and remove heat energy. • The water is then pumped into a second circuit, where it becomes steam and turns the turbines that provide power for electric generators. • A third water circuit carries away the excess heat and releases it into the environment.

  34. Chapter 7 Section 2 Nonrenewable Energy A Nuclear Fission Reaction The diagram below shows how a nuclear fission reaction.

  35. Chapter 7 Section 2 Nonrenewable Energy Nuclear Energy, continued Advantages and Disadvantages of Nuclear Fission • Nuclear power plants burn no fossil fuels and produce no air pollution. • However, they produce harmful radioactive materials that have very long half-lives, wastes must be stored for thousands of years. • These waste products give off harmful doses of radiation that can destroy plant and animal cells and can cause harmful changes in the genetic material of living cells.ystem is a system in which both energy and matter are exchanged with the surroundings.

  36. Chapter 7 Section 2 Nonrenewable Energy Nuclear Energy, continued Nuclear Fusion nuclear fusionthe process by which nuclei of small atoms combine to form new, more massive nuclei; the process releases energy • All of the energy that reaches Earth from the sun is produced by nuclear fusion. • Fusion reactions only occur at temperatures of more than 15,000,000°C. • The only byproduct of fusion are helium nuclei, which are harmless to living cells.

  37. Chapter 7 Section 2 Nonrenewable Energy Parts of a Nuclear Reactor

  38. Chapter 7 Section 3 Renewable Energy Objectives • Explainhow geothermal energy may be used as a substitute for fossil fuels • Comparepassive and active methods of harnessing energy from the sun • Explainhow water and wind can be harnessed to generate exlectiricty

  39. Chapter 7 Section 3 Renewable Energy Geothermal Energy renewable resourcea natural resource that can be replaced at the same rate at which the resource is consumed geothermal energy the energy produced by heat with Earth • The resulting steam from water passing by nearby magma or hot gases related by magma, deep in the earth, produces a large amount of geothermal energy. • Engineers and scientists have harnessed geothermal energy by drilling wells to reach the hot water. • The steam and hot water are used as a source of heat and as sources of power to drive turbines, which generate electricity.

  40. Chapter 7 Section 3 Renewable Energy Solar Energy solar energythe energy received by Earth from the sun in the form of radiation • Solar energy can be converted to heat energy in many different ways. • In a passive system, sunlight enters the house and warms the building materials, which stores some heat for the evening. • An active system includes the use of solar collectors and photovoltaic cells to collect heat or convert solar energy into electricity.

  41. Chapter 7 Section 3 Renewable Energy Energy from Moving Water hydroelectric energyelectrical energy produced by the flow of water • Moving water is one of the oldest sources of energy. Energy can be harnessed from the running water of rivers and streams or from ocean tides. • Today, 11% of the electricity in the United States comes from hydroelectric power plants. • At a hydroelectric plant, massive dams hold back running water and channel the water through the plant. Inside the plant, the water spins turbines, which turn generators to produce electricity.

  42. Chapter 7 Section 3 Renewable Energy Energy from Biomass biomass plant material, manure, or any other organic matter that is used as an energy source • Biomass is a major source of energy in many developing countries. • Bacteria that decompose the organic matter produce gases, such as methane that can be burned. • Liquid fuels, such as ethanol, also form from the action of bacteria on biomass. • More than half of all trees that are cut down are used as fuel for heating or cooking.

  43. Chapter 7 Section 3 Renewable Energy Reading check Name three sources of renewable energy.

  44. Chapter 7 Section 3 Renewable Energy Reading check, continued Name three sources of renewable energy. Answers may vary but should include three of the following: geothermal, solar, hydroelectric, and biomass.

  45. Chapter 7 Section 3 Renewable Energy Energy from Wind • Wind energy is now being used to produce electricity in locations that have constant wind. • Wind farms may have hundreds of giant wind turbines that can produce enough energy to meet the electricity needs of entire communities. • Wind generators are not practical everywhere. Because the wind does not always blow, wind energy cannot be depended on as an energy source for every location.

  46. Chapter 7 Section 3 Renewable Energy How a Hydroelectric Dam Generates Electricity The diagram below shows how dams generate electricity.

  47. Chapter 7 Section 3 Renewable Energy Tidal Energy

  48. Section 4 Resources and Conservation Chapter 7 Objectives • Describetwo environmental impacts of mining and the use of fossil fuels. • Explaintwo ways the environmental impacts of mining can be reduced. • Identifythree ways that you can conserve natural resources.

  49. Section 4 Resources and Conservation Chapter 7 Resources and Conservation • The limited supply of fossil fuels and other traditional energy resources has inspired research into possible new energy resources. • Scientists are studying how the use of traditional energy sources affects Earth’s ecosystems. • They estimate that the worldwide coal reserves will last about 200 years, and within 20 years, humans will have used half of Earth’s oil supply. • We have also learned that mining can damage or destroy fragile ecosystems. Also, fossil fuels and nuclear power may add pollution to Earth’s air, water, and soil.

  50. Section 4 Resources and Conservation Chapter 7 Environmental Impacts of Mining • Mining can cause a variety of environmental problems. • Mining may cause both air and noise pollution, water pollution, increased erosion and soil degradation, formation of sink holes, and the destruction to wildlife habitats. • Because fires in coal mines are difficult to put out, they are commonly left to burn out, which may take several decades or centuries.

More Related