Students may think that a sample of radioactive material would have half its original mass or volume after one half-life

Quantum and Nuclear


Resources to Address This

  • In many decay models the ‘decaying’ atoms are removed by some process. Use this discussion to compare the models to real radioactivity behaviour, identifying that the nucleus changes but does not disappear.

    View Resource
  • Discuss the changes in a nucleus, rather than it disappearing during decay, with this conversation outline.

    View Resource
  • Emphasise that a nucleus will change, rather than disappearing during decay by considering conservation of properties such as charge as discussed here.

    View Resource
  • The students can discuss the nature of nuclear decay by looking at the changes to radioactive atoms, showing that much of the mass of the nucleus remains after a decay.

    View Resource


  • Prather, E., () Student' Beliefs about the role of atoms in radioactive decay and half-life, Journal of Geoscience Education, 53 (4) 345-354.

    DOI: 10.5408/1089-9995-53.4.345

Limit Less Campaign

Support our manifesto for change

The IOP wants to support young people to fulfil their potential by doing physics. Please sign the manifesto today so that we can show our politicians there is widespread support for improving equity and inclusion across the education sector.

Sign today