1 / 22

Chapter 7 Notes

Chapter 7 Notes. Nuclear Changes. Chapter 7.1 Notes. Nuclear radiation Alpha particles Beta particles Gamma rays Neutron emissions. Alpha particles- are positively charged particle, emitted by some radioactive nuclei, that consists of two protons and two neutrons.

tannar
Télécharger la présentation

Chapter 7 Notes

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. Chapter 7 Notes Nuclear Changes

  2. Chapter 7.1 Notes Nuclear radiation • Alpha particles • Beta particles • Gamma rays • Neutron emissions

  3. Alpha particles- are positively charged particle, emitted by some radioactive nuclei, that consists of two protons and two neutrons. Alpha particles are the biggest type of particle can barely pass trough a piece of paper. • Beta particles- is an electron emitted during the radioactive decay of a neutron in an unstable nucleus.

  4. Gamma rays- are high energy electromagnetic radiation emitted by a nucleus during radioactive decay. Similar to light or x-rays. Gamma rays because of there high energy can travel through 60 cm of aluminum or 7 cm of lead. • Neutron emission- is the release of a high energy neutron by some neutron rich nuclei during radioactive decay. Neutron emissions have the most energy of any type of radioactive decay. It takes a block of lead about 15 cm to stop most of the neutrons emitted

  5. Radioactivity- is the process by which an unstable nucleus emits one or more particles or energy in the form of electromagnetic radiation. • Nuclear radiation- is the charged particles or energy that are emitted by an unstable nucleus. • Half-life is the amount of time it takes for half a radioactive sample to decay.

  6. Chapter 7.2 Notes Fission-(Breaking Apart) the process by which a nucleus splits into two or more smaller fragments, releasing neutrons and energy. Fusion- (Joining together) the process in which light nuclei combine at extremely high temperatures, forming heavier nuclei and releasing energy. Occurs in stars, including the sun.

  7. Nuclear fission produces energy for nuclear power and to drive the explosion of nuclear weapons. Both uses are made possible because certain substances called nuclear fuels undergo fission when struck by free neutrons and in turn generate neutrons when they break apart. This makes possible a self-sustaining chain reaction that releases energy at a controlled rate in a nuclear reactor or at a very rapid uncontrolled rate in a nuclear weapon.

  8. The mushroom cloud of the atomic bombing of Nagasaki, Japan, 1945, rose some 18 kilometers (11 mi) above the hypocenter In early August 1945, after Japan's refusal to the terms of Potsdam, the United States dropped atomic bombs on the Japanese cities of Hiroshima and Nagasaki. In the short period between the bombings, the Soviets fulfilled their part of the agreements at Yalta and invaded Japanese-held Manchuria. On August 15, 1945, Japan surrendered, thus bringing the war (WWII) to an end.

  9. Chernobyl Nuclear Accident Date and Time of the Chernobyl Nuclear Accident: The Chernobyl nuclear accident occurred on Saturday, April 26, 1986, at 1:23:58 a.m. local time. Location of the Chernobyl Nuclear Power Station: The V.I. Lenin Memorial Chernobyl Nuclear Power Station was located in Ukraine, near the town of Pripyat, which had been built to house power station employees and their families. The power station was in a wooded, marshy area near the Ukraine-Belarus border, approximately 18 kilometers northwest of the city of Chernobyl and 100 km north of Kiev, the capital of Ukraine. The Chernobyl Nuclear Power Station included four nuclear reactors, each capable of producing one gigawatt of electric power. At the time of the accident, the four reactors produced about 10 percent of the electricity used in Ukraine. The Chernobyl Nuclear Accident: On April 26, 1986, the operating crew planned to test whether the Reactor No. 4 turbines could produce enough energy to keep the coolant pumps running until the emergency diesel generator was activated in case of an external power loss. During the test, power surged unexpectedly, causing an explosion and driving temperatures in the reactor to more than 2,000 degrees Celsius—melting the fuel rods, igniting the reactor’s graphite covering, and releasing a cloud of radiation into the atmosphere.

  10. Loss of Life from the Chernobyl Nuclear Accident: By mid-2005, fewer than 60 deaths could be linked directly to Chernobyl—mostly workers who were exposed to massive radiation during the accident or children who developed thyroid cancer. Estimates of the eventual death toll from Chernobyl vary widely. A 2005 report by the Chernobyl Forum—eight U.N. organizations—estimated the accident eventually would cause about 4,000 deaths. Greenpeace places the figure at 93,000 deaths, based on information from the Belarus National Academy of Sciences. Physical Health Effects Linked to the Chernobyl Nuclear Accident: The Belarus National Academy of Sciences estimates 270,000 people in the region around the accident site will develop cancer as a result of Chernobyl radiation and that 93,000 of those cases are likely to be fatal. Another report by the Center for Independent Environmental Assessment of the Russian Academy of Sciences found a dramatic increase in mortality since 1990—60,000 deaths in Russia and an estimated 140,000 deaths in Ukraine and Belarus—probably due to Chernobyl radiation.

  11. Chernobyl reactor number four after the disaster, showing the extensive damage to the main reactor hall (image center) and turbine building (image lower left)

  12. Entrance to the Zone ofAlienation • The Zone of Alienation, which is variously referred to as The Chernobyl Zone, The 30 Kilometer Zone, The Zone of Exclusion, The Fourth Zone, or just The Zone is the 30 km/19 mi exclusion zone around the site of the Chernobyl nuclear reactor disaster. Geographically, it includes northernmost parts of Kyivs'ka oblast' and Zhytomyrs'ka oblast' of Ukraine, and adjoins the country's border with Belarus.

  13. Abandoned living blocks in the Zone

  14. Chapter 7.3 Notes • Background radiation- nuclear radiation that we are exposed to everyday. Comes from the sun, soil, water, and plants. • Radon gas- is a cancer-causing natural radioactive gas that you can’t see, smell or taste. Its presence in your home can pose a danger to your family's health. Is the leading cause of lung cancer among non-smokers. 2nd leading cause of lung cancer in America and claims about 20,000 lives annually.

  15. Problems from radiation May take days or years to show up… • Causes cells to not function properly • Cancer • Drop in white blood cells • Hair loss • Sterility • Destruction or death of bones • DNA Mutations • Skin burns

  16. Beneficial uses of nuclear radiation • Used to make smoke detectors • Treat cancer • Nuclear power • Radioactive tracers used in medicine, agriculture, and geology

  17. Nuclear fusion- would use hydrogen to run. Have never been produced in a power plant.

  18. The Radioactive Boy Scout • David Hahn (born October 30, 1976) is a man known for his attempt to build a fast breedernuclear reactor in 1994 in his backyard shed in Commerce Township, Michigan, a suburb of Detroit, at the age of 17. • Hahn, nicknamed the "Radioactive Boy Scout", is a boy scout who had previously earned a merit badge in Atomic Energy and had spent years tinkering with basement chemistry which sometimes resulted in small explosions and other mishaps. He was inspired in part by reading The Golden Book of Chemistry Experiments, and tried to collect samples of every element in the periodic table, including the radioactive ones. Hahn diligently amassed this radioactive material by collecting small amounts from household products, such as americium from smoke detectors, thorium from camping lantern mantles, radium from clocks and tritium (as neutron moderator) from gunsights. His "reactor" was a large, cored-out block of lead, and he used lithium from $1000 worth of "stolen" batteries to purify the thorium ash using a Bunsen burner.

  19. Hahn posed as an adult scientist or professor to gain the trust of many professionals in letters, despite the presence of misspellings and obvious errors in his letters to them. Hahn ultimately hoped to create a breeder reactor, using low-level isotopes to transform samples of thorium and uranium into fissionable isotopes. • Although his home-made reactor never achieved critical mass, it ended up emitting toxic levels of radioactivity, likely well over 1000 times normal background radiation. Alarmed, Hahn began to dismantle his experiments, but a chance encounter with police led to the discovery of his activities, which triggered a Federal Radiological Emergency Response involving the FBI and the Nuclear Regulatory Commission. The United States Environmental Protection Agency, having designated Hahn's mother's property as a Superfund hazardous materials cleanup site, dismantled the shed and its contents and buried them as low-level radioactive waste in Utah. Hahn refused medical evaluation for radiation exposure.

  20. On August 1st, 2007, Hahn was arrested in Clinton Township, Michigan for larceny, in relation to a matter involving several smoke detectors, allegedly removed from the halls of his apartment building. In his mug shot, his face is covered with sores which investigators claim are from exposure to radioactive materials. During a Circuit Court hearing, Hahn pleaded guilty to attempted larceny of a building. The court’s online docket said prosecutors recommended that he be sentenced to time served and enter an inpatient treatment facility. Under terms of the plea, the original charge of larceny of a building would be dismissed at sentencing, scheduled for Oct. 4.He was in fact sentenced to 90 days in jail.

  21. Work Cited • “Nuclear Fission”. March 14, 2008. http://en.wikipedia.org/wiki/Nuclear_fission • “Chernobyl Accident”. March 14, 2008. http://environment.about.com/od/chernobyl/p/chernobyl.htm • “The Zone Info”. March 14,2008. http://en.wikipedia.org/wiki/Zone_of_alienation • “WWII Info”. March 14, 2008. http://en.wikipedia.org/wiki/World_War_II • “radon info.” March 17, 2008. http://www.epa.gov/radon/ • “radioactive Boy Scout”. March 17, 2008. http://en.wikipedia.org/wiki/David_Hahn • “Radioactive boy scout photo. March 17, 2008. http://www.radjournal.com/articles/radscout/Hahn.jpg

More Related