0654.P5.1.03 — Define the terms proton number (atomic number) Z and nucleon number (mass number) A and be able to calculate the number of neutrons in a nuc: past paper questions
Real questions on 0654.p5.1.03 — define the terms proton number (atomic number) z and nucleon number (mass number) a and be able to calculate the number of neutrons in a nuc
The newest 5 of 5 written questions. Open one to see it on the real paper.
- 0654/32 · October/November 2025 · Q9b(iii)[1]
Americium‑241 has the nuclide notation 24915 Am. State the number of neutrons in the nucleus of an atom of americium‑241.
See it on the paper → - 0654/31 · May/June 2025 · Q9c(i)[1]
State the number of protons in an atom of iridium-192. number of protons =
See it on the paper → - 0654/31 · May/June 2025 · Q9c(ii)[1]
Deduce the number of neutrons in an atom of iridium-192. number of neutrons =
See it on the paper → - 0654/33 · October/November 2023 · Q9c[1]
Plutonium-239 is an example of a nuclear fuel. Plutonium-239 has the nuclide notation 239 94 Pu. Determine the number of neutrons in one atom of plutonium-239.
See it on the paper → - 0654/22 · May/June 2022 · Q39[1]
How many neutrons are in the nucleus of this type of beryllium atom?
See it on the paper →
What examiners said
Most candidates gave the correct answer. The atomic mass, 192, and the number of neutrons,115, were common incorrect answers.
— Examiner report, May/June 2025, 0654/31 Q9(c)(i) (Cambridge)
Most candidates were able to perform the correct calculation. Those that did not often gave 49 or 192.
— Examiner report, May/June 2025, 0654/31 Q9(c)(ii) (Cambridge)
Many candidates correctly determined that there are 145 neutrons in one atom of plutonium-239.
— Examiner report, October/November 2023, 0654/33 Q9(c) (Cambridge)
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