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Binding Energy
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Nucleons – protons and neutrons
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Nuclides – any species of atom
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Isotopes – same number of protons
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Isotones – same number of neutrons
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Coulomb repulsion and the strong nuclear force
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Protons vs. Neutrons
Radiation Protection and Safety
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Binding Energy
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Nuclei have energy levels similar to electrons orbiting
the nucleus.
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Protons and neutrons have spin ½
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They obey the Pauli exclusion principle
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Have a finite number of excited states
Radiation Protection and Safety
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Binding Energy
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Radiation Protection and Safety
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Binding Energy
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Nuclear reactions are typically in the MeV range
~106 times the energy of chemical reactions
 Exothermic and endothermic
 Conversion of mass to energy → E = (Δm)c2
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Relationship between atomic mass unit and energy
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For Δm: 1 u = 1.66 x 10-27 kg = 931.5 MeV
Radiation Protection and Safety
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Binding Energy
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Examples: 4He and 56Fe
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Comparison of nuclides - binding energy per nucleon
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Fusion and fission
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Radiation Protection and Safety
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Binding Energy
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Radiation Protection and Safety
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Binding Energy
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Why is the slope higher for the fusion region of the
graph?
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Total energy of decay (fission) processes
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Decay diagrams
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Radiation Protection and Safety
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