1. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter Presentation Transparencies Image and Math Focus Bank Bellringers Standardized Test Prep CNN Videos Visual Concepts Resources

3. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Atomic Energy Table of Contents Section 1 Radioactivity Section 2 Energy from the Nucleus Chapter 16

4. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Radioactivity Bellringer In your science journal write a few sentences about the term nuclear radiation. Include what you know about nuclear radiation, any benefits, and any dangers you can think of. For example, when is radiation used to help people? When is radiation harmful? Chapter 16

5. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Radioactivity Objectives Describe how radioactivity was discovered. Compare alpha, beta, and gamma decay. Describe the penetrating power of the three kinds of nuclear radiation. Calculate ages of objects using half-life. Identify uses of radioactive materials. Chapter 16

6. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Radioactivity Discovering Radioactivity An Unexpected Result Henri Becquerel discovered that radium gave off a form of radiation. Naming the Unexpected Marie Curie, a scientist working with Becquerel, named the process by which some nuclei give off nuclear radiation. She named the process radioactivity, which is also called radioactive decay. Chapter 16

7. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Radioactivity Kinds of Radioactive Decay Alpha Decay The release of an alpha particle from a nucleus is called alpha decay. An alpha particle is made up of two protons and two neutrons. Conservation in Decay In radioactive decay, the mass number is conserved, and the charge is conserved. Beta Decay The release of a beta particle from a nucleus is called beta decay. A beta particle can be an electron or a positron. Chapter 16

8. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Radioactivity Chapter 16

9. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Radioactivity Kinds of Radioactive Decay, continued Two Types of Beta Decay A carbon-14 nucleus undergoes beta decay. During this kind of decay, a neutron breaks into a proton and an electron. Not all isotopes of an element decay in the same way. A carbon-11 nucleus undergoes beta decay when a proton breaks into a positron and a neutron. Gamma Decay Energy is also given off during alpha decay and beta decay. Some of this energy is in the form of light that has very high energy called gamma rays. Chapter 16

10. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Radioactivity The Penetrating Power of Radiation Effects of Radiation on Matter Atoms that are hit by nuclear radiation can give up electrons. Chemical bonds between atoms can break when hit by nuclear radiation. Damage to Living Matter When an organism absorbs radiation, its cells can be damaged. A single large exposure to radiation can lead to radiation sickness. Chapter 16

11. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Radioactivity The Penetrating Power of Radiation, continued Damage to Nonliving Matter Radiation can also damage nonliving matter. When metal atoms lose electrons, the metal is weakened. Damage at Different Depths Gamma rays go through matter easily. They can cause damage deep within matter. The penetrating powers of different forms of radiation can be seen on the next slide. Chapter 16

12. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Radioactivity Chapter 16

13. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Radioactivity Finding a Date by Decay Carbon-14—It’s in You! During an organism’s life, the percentage of carbon-14 in the organism stays about the same. But when an organism dies, over time the level of carbon-14 in the remains drops because of radioactive decay. A Steady Rate of Decay A half-life is the amount of time it takes one-half of the nuclei of a radioactive isotope to decay. The next slide models this process. Chapter 16

14. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Radioactivity Chapter 16

15. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Radioactivity Finding a Date by Decay, continued Determining Age Carbon-14 can be used to find the age of objects up to 50,000 years old. To find the age of older things, other elements must be used. Chapter 16

16. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Radioactivity Uses of Radioactivity Radioactivity in Healthcare Doctors use tracers to help diagnose medical problems. Radioactive tracers that have short half-lives are fed to or injected into a patient. Then, a detector is used to follow the tracer as it moves through the body. Radioactivity in Industry Radioactive isotopes can also help detect defects in structures. Some space probes have been powered by radioactive materials. Chapter 16

17. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Radioactivity Chapter 16 Radioactive Tracer Click below to watch the Visual Concept. You may stop the video at any time by pressing the Esc key. Visual Concept

18. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Energy from the Nucleus Bellringer Define each of the following terms in your own words in your science journal: fission fusion Are the terms opposites, or are they similar? How is energy involved in each? Discuss your ideas with the group. Chapter 16

19. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Energy from the Nucleus Objectives Describe nuclear fission. Identify advantages and disadvantages of fission. Describe nuclear fusion. Identify advantages and disadvantages of fusion. Chapter 16

20. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Energy from the Nucleus Nuclear Fission Nuclear Fission is the process by which a large nucleus splits into two small nuclei and releases energy. Energy from Matter The nuclear fission of the uranium nuclei in one fuel pellet releases as much energy as the chemical change of burning about 1,000 kg of coal. The nuclear fission of uranium-235 is shown on the next slide. Chapter 16

21. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Energy from the Nucleus Chapter 16

22. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Energy from the Nucleus Nuclear Fission, continued Nuclear Chain Reactions A nuclear chain reaction is a continuous series of nuclear fission reactions. Chapter 16

23. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Energy from the Nucleus Nuclear Fission, continued Energy from a Chain Reaction Nuclear power plants use controlled chain reactions. The energy released from the nuclei in the uranium fuel within the nuclear power plants is used to generate electrical energy. The next slide shows how a nuclear power plant works. Chapter 16

24. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Energy from the Nucleus Chapter 16

25. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Energy from the Nucleus Advantages and Disadvantages of Fission Accidents A concern that many people have about nuclear power is the risk of an accident. What Waste! Controlled fission has been carried out for only about 50 years. But the waste will give off high levels of radiation for thousands of years. Nuclear Versus Fossil Fuel Nuclear power plants cost more to build than power plants that use fossil fuels, but often cost less to run than plants that use fossil fuels because less fuel is needed. Chapter 16

26. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Energy from the Nucleus Nuclear Fusion What Is Nuclear Fusion? In nuclear fusion, two or more nuclei that have small masses combine, or fuse, to form a larger nucleus. Plasma Needed In order for fusion to happen, the repulsion between positively charged nuclei must be overcome. Very high temperatures are needed—more than 100,000,000 °C! At these high temperatures, matter is a plasma. Chapter 16

27. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Energy from the Nucleus Advantages and Disadvantages of Fusion Less Accident Prone The concern about an accident such as the one at Chernobyl is much lower for fusion reactors. Oceans of Fuel Scientists studying fusion use hydrogen-2 and hydrogen-3 in their work. Hydrogen-1 is much more common than these isotopes. But there is enough of them in Earth’s waters to provide fuel for millions of years. Chapter 16

28. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Energy from the Nucleus Advantages and Disadvantages of Fusion, continued Less Waste The products of fusion reactions are not radioactive. So, fusion is a “cleaner” source of energy than fission is. Chapter 16

29. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Atomic Energy Use the terms below to complete the concept map on the next slide. Chapter 16 Concept Map alpha particle mass number nuclei nuclear fusion gamma ray radioactive decay nuclear fission atomic nucleus

30. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Concept Map Chapter 16

31. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Concept Map Chapter 16

32. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu End of Chapter 16 Show

33. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation Read each of the passages. Then, answer the questions that follow each passage. Chapter 16 Reading

34. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation Passage 1 Have you noticed that your forks, knives, and spoons don’t tarnish easily? Most metal utensils are made of stainless steel. Because it doesn’t tarnish, stainless steel is also used in nuclear reactors. Some scientists study radiation’s effects on metals and other substances. An important focus of their studies is radiation’s effect on the structure of stainless steel. The damage to stainless steel is caused mainly by neutron and heavy ion radiation inside nuclear reactors. Continued on the next slide Chapter 16

35. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation Passage 1, continued The radiation causes stress in the metal. The stress leads to corrosion and finally to cracking. Clearly, this feature is not desirable in parts of a nuclear reactor! Scientists hope that by studying the way radiation affects the atoms of metals, they can find a way to use the incoming radiation to make the surface stronger instead of weaker. Chapter 16

36. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 1. Which of the following happens last as stainless steel is damaged in a nuclear reactor? A The steel corrodes. B The steel is exposed to radiation. C The steel cracks. D The steel is stressed. Chapter 16

37. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 1. Which of the following happens last as stainless steel is damaged in a nuclear reactor? A The steel corrodes. B The steel is exposed to radiation. C The steel cracks. D The steel is stressed. Chapter 16

38. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 2. Which of the following is a goal of the scientists? F to use radiation to strengthen stainless steel G to keep stainless steel from tarnishing H to keep spoons and forks from cracking I to prevent stainless steel from absorbing radiation Chapter 16

39. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 2. Which of the following is a goal of the scientists? F to use radiation to strengthen stainless steel G to keep stainless steel from tarnishing H to keep spoons and forks from cracking I to prevent stainless steel from absorbing radiation Chapter 16

40. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 3. Why is stainless steel a good metal to use in a nuclear reactor? A It is made stronger by radiation. B It does not tarnish easily. C It cracks under stress. D It is not affected by radiation. Chapter 16

41. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 3. Why is stainless steel a good metal to use in a nuclear reactor? A It is made stronger by radiation. B It does not tarnish easily. C It cracks under stress. D It is not affected by radiation. Chapter 16

42. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation Passage 2 A space probe takes about 7 years to reach Saturn. What could supply energy for the cameras and equipment after that time in space? The answer is the radioactive element plutonium! The nuclei (singular, nucleus) of plutonium atoms are radioactive, so the nuclei are unstable. They become stable by giving off radiation in the form of particles and rays. This process heats the materials surrounding the plutonium, and the thermal energy of the materials is converted into electrical energy by a radioisotope thermoelectric generator (RTG). Continued on the next slide Chapter 16

43. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation Passage 2, continued Spacecraft such as Voyager, Galileo, and Ulysses depended on RTGs for electrical energy. Because an RTG can generate electrical energy for 10 or more years by using one sample of plutonium, an RTG provides energy longer than any battery can. In fact, the RTGs on Voyager were still providing energy after 20 years! Chapter 16

44. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 1. Plutonium in an RTG can be expected to provide energy for how long? A much less than 7 years B about 7 years C 10 years or more D 20 years Chapter 16

45. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 1. Plutonium in an RTG can be expected to provide energy for how long? A much less than 7 years B about 7 years C 10 years or more D 20 years Chapter 16

46. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 2. Which of the following terms has the most similar meaning to the term radioactive? F thermoelectric G plutonium H radiation I unstable Chapter 16

47. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 2. Which of the following terms has the most similar meaning to the term radioactive? F thermoelectric G plutonium H radiation I unstable Chapter 16

48. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 3. What is the final form of energy provided by RTGs? A thermal B electrical C particles and rays D nuclear Chapter 16

49. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 3. What is the final form of energy provided by RTGs? A thermal B electrical C particles and rays D nuclear Chapter 16

50. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation The table below shows the half-lives of some radioactive isotopes. Use the table below to answer the questions that follow. Chapter 16 Interpreting Graphics

51. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 1. Half of a sample of which of the following isotopes would take the longest to decay? A uranium-238 B hydrogen-3 C polonium-210 D calcium-36 Chapter 16

52. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 1. Half of a sample of which of the following isotopes would take the longest to decay? A uranium-238 B hydrogen-3 C polonium-210 D calcium-36 Chapter 16

53. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 2. How old is an artifact if only one-fourth of the hydrogen-3 in the sample remains? F 3.075 years G 6.15 years H 12.3 years I 24.6 years Chapter 16

54. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 2. How old is an artifact if only one-fourth of the hydrogen-3 in the sample remains? F 3.075 years G 6.15 years H 12.3 years I 24.6 years Chapter 16

55. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 3. How many days will it take for three-fourths of a sample of radioactive polonium-210 to decay? A 69 days B 103.5 days C 138 days D 276 days Chapter 16

56. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 3. How many days will it take for three-fourths of a sample of radioactive polonium-210 to decay? A 69 days B 103.5 days C 138 days D 276 days Chapter 16

57. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 4. How many isotopes have shorter half-lives than polonium-210? F two G three H four I five Chapter 16

58. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 4. How many isotopes have shorter half-lives than polonium-210? F two G three H four I five Chapter 16

59. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation Read each question, and choose the best answer. Chapter 16 Math

60. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 1. The Butterfly Society spent 1.5 h planting a butterfly garden on Saturday and twice as many hours on Sunday. Which equation could be used to find the total number of hours they spent planting on those 2 days? A n  2(1.5) B n  1.5  2(1.5) C n  1.5  1.5  2 D n  2  2  1.5 Chapter 16

61. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 1. The Butterfly Society spent 1.5 h planting a butterfly garden on Saturday and twice as many hours on Sunday. Which equation could be used to find the total number of hours they spent planting on those 2 days? A n  2(1.5) B n  1.5  2(1.5) C n  1.5  1.5  2 D n  2  2  1.5 Chapter 16

62. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 2. How many half-lives have passed if one-eighth of a sample of radioactive carbon-14 remains? F two G three H four I eight Chapter 16

63. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 2. How many half-lives have passed if one-eighth of a sample of radioactive carbon-14 remains? F two G three H four I eight Chapter 16

64. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 3. Which of the following shows the correct fraction of the original sample of radioactive isotope that remains after four half-lives? A 4(1/2) B (1/2)(1/4) C 4 1/2 D (1/2)(1/2)(1/2)(1/2) Chapter 16

65. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 3. Which of the following shows the correct fraction of the original sample of radioactive isotope that remains after four half-lives? A 4(1/2) B (1/2)(1/4) C 4 1/2 D (1/2)(1/2)(1/2)(1/2) Chapter 16

66. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 4. To find the area of a circle, use the equation area   r2. If the radius of circle A is doubled, how will the area of the circle change? F The area will be 1/4 as large. G The area will be 1/2 as large. H The area will be 2 times larger. I The area will be 4 times larger. Chapter 16

67. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation 4. To find the area of a circle, use the equation area   r2. If the radius of circle A is doubled, how will the area of the circle change? F The area will be 1/4 as large. G The area will be 1/2 as large. H The area will be 2 times larger. I The area will be 4 times larger. Chapter 16

68. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Radioactivity Chapter 16

69. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Energy from the Nucleus Chapter 16

70. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation Chapter 16

71. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Standardized Test Preparation Chapter 16