Nuclear Power

Locations of Nuclear Power plants in the US.

Locations of Nuclear Power plants in the World

Do Nuclear Power plants Pollute?

No they don’t. This is Steam being released.

Nuclear Power Plant Operation

Uranium ore

Nuclear Reactor Fuel Uranium ore is refined then formed into pellets.

Nuclear Reactor Fuel These Pellets are then put into Fuel rods which are Assembled Into packs of Fuel Rod Assemblies

Nuclear Reaction

This cannot Happen

Parts of an Atom What is an atom composed of? Protons Neutrons Electrons

Protons Protons have a positive charge and are located in the nucleus of the atom.

Neutrons Neutrons are located in the nucleus and have no charge

Electron are found on the outside of the atom. An electrically balanced atom will have the same number of electrons and protons Electrons

The Periodic Table

Review of Atoms Mass Number – protons (p + ) and neutrons (n 0 ) Mass Number – protons (p + ) and neutrons (n 0 ) Atomic Number – Protons (p + ) Atomic Number – Protons (p + ) Neutral Atoms = P and E Neutral Atoms = P and E If you change the atomic number it is If you change the atomic number it is a new element a new element Number of Neutrons = Mass – Atomic # Number of Neutrons = Mass – Atomic #

Isotopes Atom with same protons but different neutrons. Most have only one stable form. Atom with same protons but different neutrons. Most have only one stable form. Best Example is Hydrogen Best Example is Hydrogen

What is Nuclear Decay? Nuclear decay nucleus gives off matter and energy. Result: New element Strong Force = Holds together P and N. Larger nucleus has a weaker force.

Radioactive A nucleus with too many or too few neutrons compared to protons is considered radioactive.

Ionizing Radiation Ionizing radiation is produced by unstable atoms. Unstable atoms differ from stable atoms because they have an excess of energy or mass or both. Ionizing radiation is produced by unstable atoms. Unstable atoms differ from stable atoms because they have an excess of energy or mass or both. Unstable atoms are said to be radioactive. In order to reach stability, these atoms give off, or emit, the excess energy or mass. These emissions are called radiation. Unstable atoms are said to be radioactive. In order to reach stability, these atoms give off, or emit, the excess energy or mass. These emissions are called radiation. Ionizing radiation is produced by unstable atoms. Unstable atoms differ from stable atoms because they have an excess of energy or mass or both. Ionizing radiation is produced by unstable atoms. Unstable atoms differ from stable atoms because they have an excess of energy or mass or both. Unstable atoms are said to be radioactive. In order to reach stability, these atoms give off, or emit, the excess energy or mass. These emissions are called radiation. Unstable atoms are said to be radioactive. In order to reach stability, these atoms give off, or emit, the excess energy or mass. These emissions are called radiation.

3 types of ionizing Radiation Alpha  Helium Nucleus Alpha  Helium Nucleus Beta  Electron Beta  Electron Gamma  EM Radiation Gamma  EM Radiation These are other products that can be produced along with the new element

Ionizing Radiation alpha particle beta particle Radioactive Atom X-ray gamma ray Neutron

Alpha radiation  Nucleus of a helium atom Symbolically represented:  Chemically written: 4 He Least Destructive Radiation Can be stopped by a sheet of thick paper 2

Alpha Particles: 2 neutrons and 2 protons They travel short distances, have large mass Only a hazard when inhaled Alpha Particles

Beta radiation  Composed of one electron Composed of one electron Symbolically represented:  Symbolically represented:  Chemically written: e - or Chemically written: e - or Positron is e + or Positron is e + or More Destructive than Alpha Radiation More Destructive than Alpha Radiation Stopped by a sheet of aluminum Stopped by a sheet of aluminum

Beta Particles

Gamma radiation  High energy Electro-Magnetic Waves Has no mass or charge Symbolically represented:  Most Destructive Radiation (Most penetrating) Very difficult to stop Reduced by thick lead or concrete

Gamma Rays

Half Life Period of time it takes for a substance to decrease its mass by 1/2

Nuclear Half-Life Equation N i * (1/2) nt1/2 = N f N i * (1/2) nt1/2 = N f N i – Initial amount of radioactive material N i – Initial amount of radioactive material nt1/2 -# of half-lives nt1/2 -# of half-lives N f – Final amount of radioactive material N f – Final amount of radioactive material To get nt1/2, you must divide time given in problem by the half-life.

Nuclear halflife examples Polonium210 Polonium210 Half Life: 138 days Half Life: 138 days Alpha decay  Alpha decay  Strontium90 Strontium90 Half Life: 28.5 years Half Life: 28.5 years Beta decay  Beta decay  Cobalt60 Cobalt60 Half Life: 5.27 years Half Life: 5.27 years Gamma decay  Gamma decay 

Alpha Decay  Example Polonium210 Half Life: 138 days Alpha decay  If you have 48kg of Polonium 210, How much will be left after 138 days? How much will be left after 276 days? (2 half lives) How much will be left after 414 days? (3 half lives) Ans: 24 kg Ans: 12 kg Ans: 6 kg

Beta Decay  Example Strontium90 Half Life: 28.5 years Beta decay  If you have 30kg of Strontium 90, How much will be left after 28.5 years? How much will be left after 57 years? (2 half lives) How much will be left after 85.5 years? (3 half lives) Ans: 15 kg Ans: 7.5 kg Ans: 3.75 kg

Gamma Decay  Example Cobalt60 Half Life: 5.27 years Gamma decay  If you have 1 kg of Cobolt 60, How much will be left after 5.27 years? How much will be left after years? (2 half lives) How much will be left after years? (3 half lives) Ans: 0.5 kg Ans: 0.25 kg Ans: kg

Nuclear Reactions Decaying nucleus releases particles or energy. Decaying nucleus releases particles or energy. Creates new atoms or elements Creates new atoms or elements A Released mass = released energy. A Released mass = released energy. E = mc 2 Some are used in medicines

Nuclear Fission Splitting a nucleus = two smaller nuclei (smaller mass) = Big energy ex) Atomic Bombs and Nuclear Reactors Chain Reaction = Ongoing fission Ex) box of mouse traps, once one hits it causes the others to snap Critical Mass = Amount of material need to keep a constant rate in our chain reaction

Nuclear Fusion Joining of two nuclei, smaller mass= Larger nucleus with larger mass Joining of two nuclei, smaller mass= Larger nucleus with larger mass Must have a very high rate of speed to overcome the natural tendency to repel. Must have a very high rate of speed to overcome the natural tendency to repel. Ex) Sun and Stars Ex) Sun and Stars