The newest 13 of 14 written questions. Open one to see it on the real paper.
State the name of the process by which energy is obtained in a nuclear power station.
See it on the paper →State the number of protons and number of neutrons in a nucleus of this isotope. Number Protons number of neutrons =
See it on the paper →Uranium-238 has the nuclide notation 23982 U. Describe the composition of the nucleus of a uranium-238 atom.
See it on the paper →State the composition of an α‑particle.
See it on the paper →State the composition of an α‑particle.
See it on the paper →Describe the difference between the processes of nuclear fusion and nuclear fission.
See it on the paper →In a nuclear power station, the process of nuclear fission is used to generate electrical power. Describe the process of nuclear fission.
See it on the paper →State the number of protons in a nucleus of uranium-235.
See it on the paper →A number of responses did not include the term nucleus. There were some good answers, but many were very vague and did not demonstrate a clear understanding of the processes.
— Examiner report, May/June 2025, 0654/41 Q9(d) (Cambridge)
Candidates should use the terminology as given in the syllabus. Candidates often tried to describe nuclear fission with no reference to nuclei.
— Examiner report, May/June 2025, 0654/42 Q11(a) (Cambridge)
The number of protons was generally identified by many of the candidates.
— Examiner report, May/June 2025, 0654/42 Q11(b)(i) (Cambridge)
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Determine the number of neutrons in a nucleus of uranium-235.
Fig. 6.3 shows how a sample of rubidium-87 decays. 100 90 80 70 60 rubidium-87 remaining in sample / % 50 40 30 20 10 0 0 50 100 150 time / billion years 200 Fig. 6.3 Use Fig. 6.3 to determine the half-life of rubidium-87. Give a suitable unit for your answer. half-life = unit
See it on the paper →Asteroids are thought to be 5 billion years old. Use Fig. 6.3 to determine the percentage of rubidium-87 that has decayed to strontium-87 in the asteroid. percentage = %
See it on the paper →The lava contains the isotope potassium‑40. 40 The nuclide notation is 19 K . State the number of protons and neutrons in the nucleus of potassium‑40. number of protons
See it on the paper →Argon gas is used in some types of lamp. An argon atom has the chemical symbol 41 8 0 Ar. State the composition of the nucleus of an atom of Argon.
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