Atomic Energy Overview Boy Scout Merit Badge 2006 American Nuclear Society

Schedule  9:00-9:55Introduction  10:00-10:40 Station 1  10:45-11:25 Station 2  11:30-12:10 Lunch  12:15-12:55Station 3  1:00-1:40Station 4  1:45-2:25Station 5  2:30-3:00Wrap-Up/Sign Blue Cards

Blue Cards Put my name in appropriate spot Workshop Leader Address Line 1 Address Line 2 Phone Number

Requirements 1a. Radiation Effects 1b. Drawing of radiation symbol 2. Definitions 2. Definitions 3. Scientists 3. Scientists 4a. Model of atoms 4a. Model of atoms 4b. Fission pictures 4b. Fission pictures 4c. Critical Mass 4c. Critical Mass 5c. Time, distance and shielding 5c. Time, distance and shielding 5f. X-ray facility 5f. X-ray facility 5g. Cloud Chambers 5g. Cloud Chambers 6b. US nuclear reactors 6b. US nuclear reactors 7. Nuclear Careers 7. Nuclear Careers

Brief History of the Atom  500 BCDemocritusAtom  Long time(Romans  Dark Ages)  1808 ADDaltonPlum Pudding  1911RutherfordNucleus  1913BohrOrbits  1920’sMany PeopleQuantum Mechanics

So What is an Atom?  Atoms are made up of protons, neutrons & electrons Protons: + chargeProtons: + charge Neutrons: no chargeNeutrons: no charge Electrons: - chargeElectrons: - charge  Atoms want to have no net charge #protons = #electrons#protons = #electrons

Mass of an Atom  Masses Proton: 1 amuProton: 1 amu Neutron: 1 amuNeutron: 1 amu Electron: amuElectron: amu  So mass of atom ~ #neutrons + #protons#neutrons + #protons

What is the mass of:  Helium? 2 protons, 2 neutrons, 2 electrons2 protons, 2 neutrons, 2 electrons  Oxygen 8 protons, 8 neutrons, 8 electrons8 protons, 8 neutrons, 8 electrons  Fissile Uranium 92 protons, 143 neutrons, 92 electrons92 protons, 143 neutrons, 92 electrons  Alpha particle 2 protons, 2 neutrons2 protons, 2 neutrons

Isotopes  Isotopes are similar elements with different amounts of neutrons  There are similar properties  Some have very different properties  Stable and unstable versions of atoms

Example  Sodium – protons, 12 neutrons11 protons, 12 neutrons Very plentiful, in salt that you eat (NaCl)Very plentiful, in salt that you eat (NaCl)  Sodium – protons, 13 neutrons11 protons, 13 neutrons Not naturalNot natural Highly radioactive, beta decayHighly radioactive, beta decay Used to find leaks in industrial pipesUsed to find leaks in industrial pipes

Put together models of:  Hydrogen 1 Proton, 1 electron1 Proton, 1 electron  Deuterium 1 Proton, 1 neutron, 1 electron1 Proton, 1 neutron, 1 electron  Tritium 1 Proton, 2 neutrons, 1 electron1 Proton, 2 neutrons, 1 electron  What are the atomic and mass numbers of each isotope?  What are the net charges?  (Requirement 4a)

Fission vs. Fusion  Fission Makes 20% of our electricityMakes 20% of our electricity Breaking apart of Heavy NucleiBreaking apart of Heavy Nuclei Nuclear Reactor tour later Today!Nuclear Reactor tour later Today! Example:Example:  N + U-235  Ba Kr N  Fusion Powers the SunPowers the Sun Hard to get on EarthHard to get on Earth Combination of Light NucleiCombination of Light Nuclei IEC Fusion Tour later Today!IEC Fusion Tour later Today! Example:Example:  H-3 + H-2  N + He-4  Tritium + Deuterium  neutron + Helium

Where does radiation come from?  The sun  Soil, water and vegetation  Internal sources Potassium-40 (bananas)Potassium-40 (bananas) Carbon-14 (air)Carbon-14 (air) Lead-210 (radon)Lead-210 (radon)  Man-made sources Medical sources (x-rays, radiation…)Medical sources (x-rays, radiation…) Nuclear PowerNuclear Power

Types of Radiation Ionizing radiation Produces ions in the material it strikesProduces ions in the material it strikes  Non-ionizing radiation Can cause damage by physically striking materialCan cause damage by physically striking material

Ionizing radiation  Alpha particles  Beta particles  Photons Gamma raysGamma rays X-raysX-rays

Non-Ionizing Radiation  Low energy photons Such as light, infrared light, etcSuch as light, infrared light, etc  Neutrons Neutral particle in nucleusNeutral particle in nucleus Like a proton but with no chargeLike a proton but with no charge

Radiation Penetration

Radioactive Material  What is it? Material that releases radiation.Material that releases radiation.  How do we get rid of it? When an atom decays, it may or may not be radioactive still. Eventually, it will decay to a stable atomWhen an atom decays, it may or may not be radioactive still. Eventually, it will decay to a stable atom

Decay  Radioactive material has a probability of decaying  Overtime, this probability averages into a half life  Half-life: Amount of time it takes for half of the radioactive substance to decay

Biological Effects of Radiation  Deterministic responses which increase in severity with increased dose (sunburn)responses which increase in severity with increased dose (sunburn)  Stochastic effects which have an increased probability of occurrence with increased dose, but whose severity is unchanged (skin cancer)effects which have an increased probability of occurrence with increased dose, but whose severity is unchanged (skin cancer)

Radiation Exposure  To avoid accidental exposure, we use the radiation hazard symbol  Colors Magenta or BlackMagenta or Black Yellow BackgroundYellow Background  Color one of your own Why must people use radioactive materials carefully?Why must people use radioactive materials carefully? (Requirement 1a and 1b)

2006 Atomic Energy Boy Scout Merit Badge