The atom: past paper questions
Real questions on the atom
The newest 20 of 58 written questions. Open one to see it on the real paper.
- 0625/31 · May/June 2026 · Q4b(i)[4]
Describe how a power station generates electrical power by burning fossil fuels.
See it on the paper → - 0625/31 · May/June 2026 · Q4b(ii)[2]
State two disadvantages of generating electrical power by burning fossil fuels. Ignore the costs of building and running the power station.
See it on the paper → - 0625/41 · May/June 2026 · Q10a[2]
An isotope of uranium has 92 protons and 143 neutrons in each nucleus. Complete the nuclide notation for this isotope. U
See it on the paper → - 0625/32 · February/March 2026 · Q10a[2]
Determine the number of: protons in one nucleus of iodine‑125, neutrons in one nucleus of iodine‑125.
See it on the paper → - 0625/32 · February/March 2026 · Q10b[3]
Iodine‑125 has a half‑life of 60 days. A radioactive source contains 40 mg of iodine‑125. Calculate the mass of iodine‑125 that remains in the source after 180 days. mass of iodine‑125 remaining = mg
See it on the paper → - 0625/32 · February/March 2026 · Q10c[2]
Iodine‑123 is another isotope of iodine. State the meaning of the term, isotope.
See it on the paper → - 0625/31 · October/November 2025 · Q10a[2]
Write the nuclide notation for radium-223.
See it on the paper → - 0625/31 · October/November 2025 · Q10b[1]
number of neutrons = (b) Determine the number of neutrons in one nucleus of radium-223.
See it on the paper → - 0625/32 · October/November 2025 · Q9b(i)[2]
State the meaning of the term isotope.
See it on the paper → - 0625/33 · October/November 2025 · Q9a[3]
Table 9.1 shows information about particles in an atom. Complete the table. Table 9.1 particle charge on particle location of particle neutron in the nucleus negative positive
See it on the paper → - 0625/41 · October/November 2025 · Q9a[3]
Describe the structure of an atom of helium-4, 24 He.
See it on the paper → - 0625/41 · October/November 2025 · Q9b(i)[2]
State what happens during nuclear fusion reactions which form helium. (i)
See it on the paper → - 0625/43 · October/November 2025 · Q8a(i)[1]
Observation: most of the particles pass straight through the foil. conclusion
See it on the paper → - 0625/33 · May/June 2025 · Q10a(i)[1]
State the number of protons in one nucleus of radon-222. number of protons = (i)
See it on the paper → - 0625/33 · May/June 2025 · Q10a(ii)[1]
number of neutrons = Determine the number of neutrons in one nucleus of radon-222. (ii)
See it on the paper → - 0625/33 · May/June 2025 · Q11b(i)[2]
The Sun consists mainly of two elements. Name the two elements. and
See it on the paper → - 0625/32 · February/March 2025 · Q5a[2]
After lifting the load, the motor is switched off. Fig. 5.2 represents the transfer of energy from the battery to the load in Fig. 5.1. In Fig. 5.2, add the names of the energy stores. energy store in the battery kinetic energy in the electric motor and the moving load energy store in the load
See it on the paper → - 0625/32 · February/March 2025 · Q11a[3]
Table 11.1 gives information about the particles in an atom. Table 11.1 name of particle relative charge location in the atom proton +1 in the nucleus neutron electron orbiting the nucleus Complete the table by writing the correct information in the three empty spaces.
See it on the paper → - 0625/42 · February/March 2025 · Q9a(i)[1]
Explain what isotopes are.
See it on the paper → - 0625/42 · February/March 2025 · Q9a(ii)[2]
Complete Table 9.1 for strontium-90. Table 9.1 particle number in one atom location 38 outside nucleus 38 inside nucleus neutron (ii)
See it on the paper →
What examiners said
Comprehensive responses • Most candidates were able to correctly analyse the nuclide notation and use their knowledge to determine the numbers of protons and neutrons in the iodine isotope. Limited responses • Some candidates transposed the proton and neutron numbers.
— Examiner report, February/March 2026, 0625/32 Q10(a) (Cambridge)
Comprehensive responses • Some candidates displayed good knowledge of the concept of half-life and were able to use data from the question to determine that 180 days was equal to 3 half-lives for iodine-125. Few of these candidates were then able to use the idea of 3 half-lives to calculate the mass of iodine-125 remaining after 180 days as 5.0 mg. Limited responses • Some candidates recognised t...
— Examiner report, February/March 2026, 0625/32 Q10(b) (Cambridge)
Comprehensive responses • Many candidates displayed good understanding of the term isotope and gave clear descriptions in terms of the same numbers of protons but different numbers of neutrons. Limited responses • Some candidates transposed the numbers of protons and neutrons and so gave incorrect statement such as: An isotope has the same number of neutrons but different numbers of protons.
— Examiner report, February/March 2026, 0625/32 Q10(c) (Cambridge)
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