Sub-topic 1
2025 · National Preliminary
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Identifying the missing nuclide in a balanced nuclear fission equation
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Sub-topic 2
2026 · National One-Eighth
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Identifying the missing nuclide in a balanced nuclear fission equation
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Sub-topic 3
2026 · National Preliminary
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The three subatomic particles that make up a nuclide
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Sub-topic 4
2025 · National Semifinal
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Periodic group of the daughter nuclide after a sequence of alpha and beta decays
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Sub-topic 5
2024 · National Semifinal
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Nucleon number density of a nucleus from the nuclear radius parameter r0
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Sub-topic 6
2018 · National Preliminary
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Types of nuclear reactions: decay versus bombardment
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Sub-topic 7
2018 · National Preliminary
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Why neutrons are favoured for nuclear bombardment
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Sub-topic 8
2018 · National One-Eighth
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Identifying a nuclide from a neutron-alpha bombardment reaction
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Sub-topic 9
2023 · National One-Eighth
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Identifying nuclides from beta decay, positron decay and electron capture
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Sub-topic 10
2021 · National Preliminary
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Change in n/p ratio during alpha emission (true/false)
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Sub-topic 11
2024 · National One-Eighth
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Number of neutrons in the product nuclide of a bombardment reaction
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Sub-topic 12
2017 · National Quarterfinal
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Electrons in a neutral atom before electron capture, from the daughter nuclide's atomic number
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Sub-topic 13
2026 · National Preliminary
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Identifying an isotone (same neutron number) of a given nuclide
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Sub-topic 14
2025 · National Preliminary
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Distinguishing isotopes from isotones by atomic number, mass number and decay mode (true/false)
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Sub-topic 15
2025 · National One-Eighth
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Logical relationships between isotopes, isobars and isotones for three related nuclides (true/false)
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Sub-topic 16
2012 · National Preliminary
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Penetrating vs ionizing power of gamma rays
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Sub-topic 17
2012 · National Preliminary
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High ionizing power of alpha particles
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Sub-topic 18
2013 · National Preliminary
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Atomic number is unchanged by neutron absorption (true/false)
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Sub-topic 19
2013 · National Preliminary
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Atomic number is unchanged by gamma decay (true/false)
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Sub-topic 20
2013 · National Preliminary
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Mass number increases by one on neutron absorption (true/false)
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Sub-topic 21
2013 · National Preliminary
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Conserved quantity in a nuclear reaction
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Sub-topic 22
2013 · National Quarterfinal
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Product isotope from beta-minus decay of sodium-24
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Sub-topic 23
2013 · National Quarterfinal
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Product isotope from positron emission of sodium-22
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Sub-topic 24
2013 · National Quarterfinal
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Product isotope from proton emission of sodium-18
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Sub-topic 25
2013 · National Quarterfinal
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Product isotope from beta-minus decay of sodium-24 (repeat)
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Sub-topic 26
2014 · National Final
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The neutrino as a fundamental particle among deuteron/alpha particle/neutrino
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Sub-topic 27
2014 · National Final
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Carbon-14 beta decay produces nitrogen-14 (true/false)
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Sub-topic 28
2014 · National Final
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Carbon-14 forms from nitrogen-14, not carbon-12, via cosmic-ray bombardment (true/false)
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Sub-topic 29
2017 · National Quarterfinal
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Isotones share the same neutron number (true/false)
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Sub-topic 30
2017 · National Quarterfinal
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Same total nucleon count defines isobars, not isotopes (true/false)
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Sub-topic 31
2017 · National Quarterfinal
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Same nucleon count means same mass number, by definition (true/false)
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Sub-topic 32
2017 · National Quarterfinal
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Riddle: mass defect, the nucleon-mass/nuclear-mass difference
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Sub-topic 33
2022 · National Preliminary
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Beryllium-9 plus hydrogen forms lithium-6 and an alpha particle
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