The Nucleus of the Atom

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The Nucleus of the Atom

• Chapter 12

Great Idea Nuclear energy depends on the
conversion of mass into energy
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Chapter Outline

• Empty Space, Explosive Energy
• The Organization of the Nucleus
• Radioactivity
• Energy from the Nucleus

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Empty Space, Explosive Energy
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Empty Space, Explosive Energy

• Relation of atom to nucleus
• What goes on in the nucleus has almost nothing to
  do with the atoms chemistry, and vice versa
• The energies available in the nucleus are much
  greater than those available among electrons
• Emc2

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The Organization of the Nucleus
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The Organization of the Nucleus

• Rutherford
• Nucleus
• Proton
• neutron
• Nucleus gives atom its mass

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Atomic Numbers, Isotopes,and the Mass Number

• Atomic number
• of protons in nucleus
• Defines chemical behavior
• Isotopes
• Elements with different numbers of neutrons
• Mass number
• Total protons and neutrons

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The Strong Force

• Strong force
• Holds nucleus together
• Operates over short distances
• Binding energy

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Radioactivity
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Whats Radioactive?

• Radioactivity or radioactive decay
• Radiation

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The Kinds of Radioactive Decay

• Alpha Decay
• Release of particle
• Composed of 2 protons and 2 neutrons
• Beta Decay
• Emission of electron
• Neutrino
• Effect
• Weak Force
• Gamma Radiation
• Electromagnetic radiation

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Moving Down the Chart of the Isotopes
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Radiation and Health

• Ionization
• Stripping electron(s)
• Long-term effects
• Cancer
• Birth defects

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Half-Life

• Half-life
• Average time for decay of ½ batch of radioactive
  isotopes
• Wide range of half-lives
• Cannot predict half-life

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Radiometric Dating

• Radiometric dating
• Measurement of half-life
• Carbon-14
• Half-life 5700 years
• Geology
• Need longer half-lives

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Decay Chains

• Decay chains
• Series of decays
• Continues until stable isotope appears

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Indoor Radon

• Decay of Uranium-238
• Radon-222
• Can build up
• Increase ventilation

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Energy from the Nucleus
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Nuclear Fission

• Fission
• Splitting of nuleus
• Nuclear Reactor
• Extracts energy
• Meltdown

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Fusion

• Fusion
• 2 atoms of H combine to form He
• Some mass converted to energy
• Sunlight