Sub-topic 1
2018 · National Preliminary
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Riddle: the mass spectrometer
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Sub-topic 2
2025 · National Preliminary
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Components of a mass spectrometer: ionization chamber, mass analyzer and detector
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Sub-topic 3
2021 · National Preliminary
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Number of mass-spectrum peaks for a tetra-atomic molecule of an element with two isotopes
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Sub-topic 4
2021 · National Quarterfinal
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Atoms of an element with different mass numbers are isotopes of each other
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Sub-topic 5
2021 · National Quarterfinal
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Riddle: tritium, the radioactive hydrogen isotope that decays to helium-3
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Sub-topic 6
2022 · National Preliminary
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Sum of protons, electrons and neutrons in the most stable isotope of sodium
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Sub-topic 7
2022 · National Preliminary
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Riddle: the mass spectrometer, identifying compounds via mass-to-charge ratio
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Sub-topic 8
2023 · National Preliminary
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Protons, neutrons and electrons in chromium-55
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Sub-topic 9
2023 · National Preliminary
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Protons, neutrons and electrons in copper-65
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Sub-topic 10
2023 · National Preliminary
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Protons, neutrons and electrons in cobalt-59
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