Fusion and Fission Reactions


  • Splitting apart the nucleus and releasing energy (heat).
  • Radiation can be caused by a neutron striking it.
  • More complex atoms are produced and are unstable and radioactive.
  • This produces energy for nuclear power plants and nuclear weapons.


  • Combining small nuclei by high-pressure and temperature.
  • Produces new elements that are stable and non-radioactive
  • This process powers active stars

Fission Example

Mass defect: when total mass is less than starting mass (missing mass is changed into energy)