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.]
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SCIENCE EDUCATIONAL NEWS VOL 66 NO 4
α β–
β+ γ