Decay equations on the N–Z chart sim
Choose α, β or γ decay (or follow the uranium-238 chain to lead-206), move a magnetic nucleus counter to the new nucleus on an N–Z chart board, and balance the decay equation by typing the new nucleus's A, Z and symbol and the particle's numbers.
Radioactivity: decay equations · covers the O-Level, IGCSE, GCSE topic
What the sim shows
Model: the rules for α decay (A − 4, Z − 2), β decay (A the same, Z + 1) and γ emission (no change), as in the O-Level, IGCSE and GCSE courses. The chart is a 11 × 9 window of the N–Z chart drawn as a bare grid; it moves with the nucleus when the nucleus nears its edge. The nuclei are real; the uranium-238 chain follows its main branch to lead-206. β+ decay and the antineutrino are left out (beyond the syllabus). Half-lives are from memory, rounded. Nothing runs on its own: the counter moves only when you move it.
- The part you move: the nucleus counter on the chart board
- The magnetic N–Z chart board on its feet, the tray of α, β and γ tiles, spare counters, a marker and an eraser
Use it in your lessons
- Try it here: anyone can unlock 2 figures free, and a free account unlocks up to 5. Runs on a laptop, a Chromebook or a phone; nothing to install.
- Present it and share student links with the teacher plan, from US$5 a month, billed yearly.
- Put it on your own website or LMS for US$9, paid once, or every sim from US$29 a month.
Free guide: 12 practicals as sims, and how to run one in a lesson →
Need a version for your exact set-up? Have one made: US$49 a figure in an order of 5.
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