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Thursday, February 2nd. Quick write: Take the article from desk Read the article Questions: What is Fission? What is fusion? Who is Lise Meitner? Homework: Complete the accompanying Review sheet . SWBAT: Identify fusion and fission Label Nuclear Fission and Nuclear Fusion
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Thursday, February 2nd Quick write: • Take the article from desk • Read the article • Questions: • What is Fission? • What is fusion? • Who is Lise Meitner? Homework: • Complete the accompanying Review sheet • SWBAT: • Identify fusion and fission • Label Nuclear Fission and Nuclear Fusion • article reading and discussion
Nuclear Atoms • Fission: binary fission/splitting/biology term : ) • The splitting of an atomic nucleus into two smaller nuclei having almost the same mass, the missing mass is in the form of energy • Fusion: to bring together • The joining of two low mass nuclei to form a single larger nucleus to produce helium and energy
Nuclear Fission • How? • The bombardment of a neutron or nuclear “bullet” to Uranium-235 • Forming Barium-141 nucleus and Krypton-92 nucleus • With the release of 2 or 3 neutrons • Energy released from Uranium-235 is not great • The neutrons cause the most damage by splitting more uranium nuclei • Known as: • Nuclear chain reaction: • A continuous series of fission occurrences • Continues until there is no more Uranium-235 • Atomic Bomb • An uncontrolled nuclear chain reaction
Nuclear fission – splitting the atom. 235U + 1n 90Sr + 143Xe + 31n More neutrons are released to keep the reaction going.
Nuclear Fusion • How? • Temperatures must reach over a million degrees Celsius • This forms plasma! • Its products form a mass of 1% less than its reactants • The loss of mass is converted to a tremendous amount of energy • Hydrogen Bomb is result to nuclear fusion. • Fusion requires nuclear fission to stimulate the reaction artificially • The sun’s energy is powered by fusion
Nuclear fusion – joining small atoms. 2H + 3H 4He + 1n Hydrogen atoms combine to form helium in a star.
Friday, February 3rd • SWBAT: • Compare fusion and fission • Label Nuclear Fission and Nuclear Fusion • Side effects to radiation • article reading and discussion Quick write: • Take sheet from desk and article • Read directions to the assignment Homework: • Read your article • Work on your article summary outline due Wednesday • Article summary and response due Monday, February 13th, it must be typed!
Nuclear Fusion • Benefits of fusion: • Energy is greater • Produces less radioactive wastes • Fuels are more plentiful • Disadvantages: • Very difficult to begin, control and maintain • Temperature requirements are extremely too hot to manage • Thermonuclear: reaction that requires a lot of heat NRC: The Boiling Water Reactor (BWR)
Nuclear Fission • Benefits: • Controlled fission is used to operate nuclear power plants • Controlled Nuclear Reaction • The energy is in the form of heat, then used to produce electricity • Disadvantages: • Does not create as much energy as fusion
Monday, February 6th • SWBAT: • Compare fusion and fission • Label Nuclear Fission and Nuclear Fusion • different forms of ionization management • article reading and discussion Quick write: • Read the article • What is the function of the magnetic field? • How is the plasma created? • What is the tokamak? Fusion energy: The tokamak Homework: • Web Quest due Friday • Read your article • Work on your article summary outline due Wednesday • Article summary and response due Monday, February 13th, it must be typed!
Name ___________________________Web Quest http://kentshillphysics.net/nuc5.htm Answer the following: • Describe what is a chain reaction. • What is the role of a control rod? • Explain a typical fission reaction and write out an equation for the reaction. • What can fission be used for in your life? • Explain a typical fusion reaction and write out an equation for the reaction. • Sketch and label each segment of a nuclear power plant
Tuesday, February 7th • SWBAT: • different forms of ionization management • describe each segment of an nuclear power plant Quick write: • Take work sheet from desk • Label the diagram Homework: • Web Quest due Friday • Read your article • Work on your article summary outline due TOMORROW • Article summary and response due Monday, February 13th, it must be typed!
1. Energy released in a nuclear reaction (fission or fusion) comes from the fractional amount of mass converted into energy.2. Nuclear changes convert matter into energy. Mass Deficit • E=mc2 • The energy released is equal to the mass lost (m) times the speed of light (c) squared. • Relationship between mass and energy. • Developed by Albert Einstein • Speed of light: 299,792,458 meters per sec
Detecting and Managing Radioactivity 1. Electroscope • A metal rod with two thin metal leaves at one end to detect radiation. How it works! • If a negative charge is detected the metal leaves separate • Because radioactive substances remove electrons, the molecules in the air become more positive • These positive charged molecules are sensed by the electroscope which pulls the negatively charged leaves away from each other. • The Electroscope
Detecting and Managing Radioactivity . . . . 2. Geiger Counter • 1928: Hans Geiger designed an instrument to measure and detect radiation • In the presence of radiation it produces an electrical current How it works! • There is a tube filled with gas (argon or helium) • If radiation enters the tube it will remove electrons from the gas atoms becoming cation atoms • This sets off a current which can be measured Other Detection Devices
Detecting and Managing Radioactivity . . . . 3. Cloud Chamber • 1911: Charles Wilson designed the cloud chamber which enables you to visually see the path of ionization as well as photograph it How it works! • The container is glass or plastic sitting on dry ice • Once the radiation enters the chamber it will interact with condensed alcohol seeds. • You can see a trail of the seeds forming The Cloud Chamber
Detecting and Managing Radioactivity . . . . 4. Bubble Chamber • 1952: Donald A. Glaser created this vessel • 1960: He received a Nobel Prize for his invention How it works! • A large chamber uses a superheated transparent liquid (often liquid hydrogen is used) to react with charged particles to detect radiation.
Wednesday, February 8th • SWBAT: • Place the parts of each nuclear equation in order. • Describe each segment of an nuclear power plant. • Identify each segment of a nuclear power plant. Quick write: • Take a sheet from the desk • Read the article and answer the following: • What is the reading about? • How is it related to science and history? • How do you feel about the reading? Homework: • Web Quest due Friday • Test Moved to Next Wednesday! • Article summary and response due Monday, February 13th, it must be typed!
Wednesday, February 8th • SWBAT: • Place the parts of each nuclear equation in order. • Describe each segment of an nuclear power plant. • Identify each segment of a nuclear power plant. Quick write: • Take a sheet from the desk • Read the article and answer the following: • What is the reading about? • How is it related to science and history? • How do you feel about the reading? Homework: • Web Quest due Friday • Test Friday! • Article summary and response due Monday, February 13th, it must be typed!
235U + 1 neutron >>>> 2 neutrons + 92Kr + 142Ba + ENERGY 235U + 1 neutron >>>> 2 neutrons + 92Sr + 140Xe + ENERGY
2H + 3H ----> 4He + n 2H + 3H ----> 4He + n 2H + 3H ----> 4He + n
Review of Nuclear Reactions • Basic Nuclear Fission
What is a Nuclear Reactor? • It is a controlled system that holds sustainable nuclear chain reactions. Usages: • generating electricity • moving aircraft carriers and submarines • producing medical isotopes for imaging and cancer treatment • research
What are the parts of a Nuclear Reactor? • Control rods: • Extra neutrons are absorbed and/or soaked up • When the rods are lowered: slows down the process • When the rods are raised: speeds up the process • Core: • Contains the nuclear fuel in the rods, using U-235, this is the site of nuclear fission • Concrete Casing: • Acts as a barrier to protect workers from the radiation produced • Moderator: • Enables the neutrons to slow down to a speed where nuclear fission can take place in the nucleus. • Generator: • Site where the heated up water spins the generator to produce a source of electricity to power your house!
What takes place after the Fuel is used? • The fuel now has nuclear waste. • The U-235 has transformed into a series of isotopes of almost every transition metal on the periodic table! • The fuel originally contained U-235, oxygen and steel. • It remains for thousands of years! Yikes! • Where? It is stored under water until the radiation decays to a level that can be maintained. • Now what? It is contained in concrete storage casks either deep under the Earth or used in recycling.
Thursday, February 9th Quick write: • Complete the following equations: _____+ 1 neutron >> _______+ Kr-92 + Ba-142 + _____ ____ + 3H ----> _____ + n + energy 2. Label which one is fusion and which equation is fission. 3. Which reaction powers the sun? 4. Which reaction causes radioactive waste? Homework: • Web Quest due Friday • Test Next Wednesday • look online for test topics! • Article summary and response due Monday, February 13th! • SWBAT: • Identify different equations of nuclear reactions • Describe each segment of a nuclear power plant. • Identify the topics for the test.
Nuclear Equations FUSION: 2H + 3H ----> 4He + n FISSION: U-235 + 1 neutron >> 2 neutrons + Kr-92 + Ba-142 + ENERGY U-235 + 1 neutron >> 4 neutrons + Sr-92 + Xe-140 + ENERGY
What is ionization? • Is a process of absorption of radiation as it penetrates through material • Changes the electrical balance of an atom • Causes ions in the material and partial or all amounts of radiation to be lost. • Two types of ions: • Cation • Anions
What is the Theory of Relativity? • Mass and energy can be converted into each other. • This supports the Theory of Conservation of Energy: • If matter is destroyed then energy is created! • If energy is destroyed than matter is created! • Therefore, the total amount of energy and mass is still conserved! • This supports the Law of Conservation of Energy, energy cannot be created nor destroyed by ordinary means.
Friday, February 10th Quick write: • Take a lab • Define Radiation, Convection and Conduction. Homework: • Test Next Wednesday • look online for test topics! • Article summary and response due Monday, February 13th! • SWBAT: • Describe Radiation, Conduction and Convection. • Observe radiation, conduction and convection.
Monday, February 13th Quick write: • Complete the Practice Test Question Worksheet. • Take out your typed article Homework: • Test Wednesday • look online for test topics! • SWBAT: • Observation of radiation, conduction and convection.
Tuesday, February 14th Quick write: • Use the image to the right and answer the following: • Write down 3 ways you can identify a Nuclear Fusion Reaction. • Write down 3 ways you can identify Nuclear Fission Reaction. • 239 Pu + n---> 233 U + 3n+ 4 He + Energy • 1. One Large nucleus forms two smaller nuclei • 2. Neutron and one atom found as a reactant • 3. U or Pu as a reactant • 2 H + 3 H---> 4 He + 1n + Energy • 1. Two smaller nuclei combining to form One larger nucleus • 2. Two Hydrogen atoms as reactants • 3. One large Helium atom as a product • SWBAT: • Complete lab on Observation of radiation, conduction and convection. • Identify the parts of the nuclear reactions. Homework: • Test Wednesday! • look online for test topics! • Only the 3 lab stations and Lab question Packet due Friday!
Other uses of radioactive isotopes • Radioactive Dating: • Geological dating: U-238 occurs naturally in rocks, used to age mountains • Dating Live Matter: • Organisms that were once alive, Carbon-14 is used to date wood, bone, animal skin or fabric. • Irradiated food • gamma rays kill bacteria, yeast and mold for storage for longer time
Other uses of radioactive isotopes • Radioactive tracers • Carbon-14 is used to follow a chemical reaction to trace for a tumor. • Medical isotopes • Technetium-99: pinpointing brain tumors • Iondine-131: diagnosis and treatment of thyroid disorders • Radium and Cobalt-60: treatment in cancer
Risks in Radioactivity • Biological Damage: • Damage and destroy cells forming burns, cataracts,, cancer • Long term Storage • Unknown future outcome! • Accidents: • Fuel and wastes escape from nuclear reactors • 1986: Chernobyl in Ukraine was destroyed by an uncontrolled chain reaction, winds spread wastes all throughout Europe • March 2011: Fukashima, Japan, nuclear reactor meltdown and nuclear wastes lost following the Tohoku earthquake and tsunami