RADIATION

Radioactive decay:  transmutation, spontaneous, half life,  emission of radiation energy; alpha, beta, gamma

Forces and nuclear stability:

strong nuclear forces: strong force, only attractive, very short distances; electro-magnetic forces:  weaker than nuclear forces, works over larger distances, repulsive in nuclei (only + charges), overwhelms attractive nuclear forces in large nuclei (making them unstable), increased number of neutrons reduces the repulsive effect; neutron instability: neutrons are unstable in isolation, decompose into a proton and an electron (beta particle), stable in the presence of a proton

Fission :  collision of a neutron and atoms – “splits” the atom, chain reaction, critical mass, energy is released because nucleons in product elements have less mass than original nucleons (mass converted to energy)

Fusion:  combine two small nuclei (must be moving very fast (ie be very hot), combination has smaller mass than the 2 originals (up to iron), loss of mass is converted to energy

  

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Define radioactive decay and half life.  How is radioactive decay fundamentally different from fusion or fission?

 Describe the three types of radiation that can be emitted during radioactive decay.  Include their composition, charge, and penetrating ability.  Which of the three has no mass?

 Describe the forces acting on protons and neutrons within the nucleus of an atom.  Explain why large elements are inherently unstable.

 Compare and contrast fission and fusion.   Explain how the size of an element (and its nucleons) controls whether an element is more likely to release energy through fusion or fission.