Science Education News (SEN) Journal 2017 Volume 66 Number 4 December 2017 | Page 57

YEARS K–6 IDEAS FOR THE CLASSROOM A box full of radiation (continued) Conclusion nucleus has a deficiency of neutrons, a proton may sacrifice itself to produce a neutron (to balance the nucleus up again) plus a positron (the anti-matter equivalent of the electron). The final product of this approach, the boxes below, should provide students with a visual representation of all of the possible outcomes of nuclear instability. When revising, it can be handy to just draw these four boxes with the different types of nuclear decay (or even just the four boxes), and see how much the students can recall, especially how much of the deeper, more interesting nuclear chemistry. This area is worthy of discussion on its own (and the work at ANU can be an interesting link), however, its real value is in the connection to isotopes that are produced in a cyclotron, and can be used for medical purposes, such as Positron Emission Tomography or PET scanning. This completes the picture about the production of medical isotopes. The second way that a neutron-deficient nucleus can attain balance is by electron capture (essentially the opposite of beta- decay). A proton in the nucleus steals an electron from the inner shell to form a neutron. This just seems scary as we are always taught that the electrons and the nucleus are two separate and separated entities, yet here we have them interacting. [NB, students who have done physics – at least the Year-12 course soon to be replaced, might be able to connect this with Heisenberg’s uncertainty principle, where the electron’s location may occasionally take it within the nucleus, where a surplus, therefore higher-energy, proton can ‘capture’ it.]   57 SCIENCE EDUCATIONAL NEWS VOL 66 NO 4 α β– β+ γ