Where the practice comes from.
Original Edexcel-aligned practice means questions and explanations written for this website and checked against the Pearson Edexcel GCSE Physics (1PH0) specification. It does not mean Pearson authored, approved or marked them.
Audit: 28 September 2026 · Issue 4, March 2024, Topic 6, printed pages 23–25.
What has been checked: 46 specification explanation tasks, 7 chapter explanation tasks, the original 12-question mixed quiz, and an expanded bank of 920 original questions (20 per point). The expanded bank was reviewed against Topic 6 and its answer keys checked, including arithmetic and nuclear conservation checks. The review was performed by the site’s AI development assistant, not an independent teacher or examiner. Relevant examples in the 2023 Foundation and Higher papers were compared where listed below. An example can assess only part of an original task. Where no individual match is recorded, that gap is shown explicitly. This is a content audit by the site’s AI development assistant, not examiner validation.
Choose any of the 46 point quizzes, each with 20 questions, or the original 12-question mixed quiz. The bank combines recall, misconception checks, numerical applications and half-life graphs. These are scaffolded practice questions, not 920 unique official assessment examples or a prediction of exam marks. Repeated numerical forms help practise a method; quiz completion alone does not prove mastery. P denotes separate Physics content, not Higher tier. Follow your teacher’s tier guidance.
Changes made in this audit
- Broader explanation prompts for particle properties, electron transitions, radiation detection, nuclear changes and other multi-part requirements.
- Reference guidance for every specification task; the original chapter tasks retain their worked explanations.
- Clear distinction between a positively charged nucleus and a neutral atom, and between isotopes and ions. The hydrogen-1 exception is made explicit.
- All 12 quiz keys checked, including beta-plus, background subtraction, half-life and control rods. No answer-key changes were needed.
- Review requests identify their author-written criteria and warn against presenting them as official mark schemes.
Expanded quiz · 920 original questions
Every item belongs to a specification point and has an answer key and feedback. After answering, “sources & answer guidance” links to that point’s official specification and any related assessment example recorded below. Those examples are topic references, not matching mark schemes for the new questions. Where an individual official example has not been mapped, that remains an open gap.
The 20-question sets are numbered 6.1–6.46P, following the same titles as the specification table below. Some items practise prerequisite knowledge or applications around the point; they are not quotations of specification statements. Scores and progress save independently for each set. Each question earns 1 point on its first correct answer only; a specification completion still earns 10 points once.
Using official past papers
A past-paper review must name its series, tier, paper code, question and subpart. Use the corresponding question and mark-scheme section, including allowances and level descriptors. A related example is not the matching mark scheme for a different question. AI feedback is still an interpretation, and must not claim to have consulted an unavailable scheme.
The official documents linked here remain on Pearson’s website and are © Pearson Education Ltd. This site is independent of Pearson.
Specification explanations
| Practice item | Original answer guidance | Related official example |
|---|---|---|
| 6.1 · Atomic structure | Almost all mass and all positive charge are in the tiny nucleus. Protons carry positive charge; neutrons are neutral. Negative electrons surround it. The nuclear radius is much smaller than the atomic radius. The whole atom is neutral. | May/June 2023 · 1PH0/1F · Q4(a)(i–iii), 4(b)(i–iii) Matching scheme for that official example |
| 6.2 · Size of atoms and small molecules | Atoms and small molecules are typically of order 10⁻¹⁰ m. A nucleus is much smaller; the exact sizes vary. | May/June 2023 · 1PH0/1F · Q4(a)(i–iii), 4(b)(i–iii) Matching scheme for that official example |
| 6.3 · Mass and atomic number notation | Z counts protons and A counts protons plus neutrons. Neutrons = A − Z = 23 − 11 = 12. Write A above Z to the left of the element symbol. | May/June 2023 · 1PH0/1F · Q4(a)(i–iii), 4(b)(i–iii) Matching scheme for that official example |
| 6.4 · Isotopes | Isotopes share a proton number and nuclear charge but differ in neutrons and mass. An ion has gained or lost electrons; its nucleus need not change. | May/June 2023 · 1PH0/1H · Q7(a–c) Matching scheme for that official example |
| 6.5 · Particle masses and charges | Proton: relative mass 1, charge +1; neutron: 1, 0; electron: about 1/1836, −1; positron: about 1/1836, +1. About 1/1840 is an acceptable rounded value. | May/June 2023 · 1PH0/1F · Q4(a)(i–iii), 4(b)(i–iii) Matching scheme for that official example |
| 6.6 · Neutral atoms | Six positive protons and six negative electrons have equal and opposite total charges, so the atom has zero net charge. Neutral neutrons do not change that balance. | May/June 2023 · 1PH0/1F · Q4(a)(i–iii), 4(b)(i–iii) Matching scheme for that official example |
| 6.7 · Electron orbits | In the GCSE atomic model, electrons occupy orbits at particular distances and energy levels around the nucleus. They cannot occupy arbitrary energies between these allowed levels. | Specification checked; individual official-example mapping open. |
| 6.8 · Absorption and emission of energy | Absorption transfers energy to an electron so it can move up a level; moving down releases electromagnetic radiation. The energy exchanged is the level difference. | Specification checked; individual official-example mapping open. |
| 6.9 · Positive ions | Losing an outer negative electron leaves more positive protons than negative electrons. The resulting positive ion has an unchanged nucleus. | Specification checked; individual official-example mapping open. |
| 6.10 · Five emissions and random decay | Alpha, beta minus, beta plus, gamma and neutron radiation can come from unstable nuclei. Random means the decay time of a particular nucleus cannot be predicted. | Specification checked; individual official-example mapping open. |
| 6.11 · Ionisation | Radiation transfers enough energy to remove an electron from an atom, leaving a charged particle. Alpha, both beta types and gamma can cause this. | May/June 2023 · 1PH0/1F · Q7(a–d) Matching scheme for that official example |
| 6.12 · Background radiation | Background is radiation detected from surrounding sources even without the source being investigated. Subtract its rate to estimate the contribution from the investigated source. | Specification checked; individual official-example mapping open. |
| 6.13 · Earth and space sources | Cosmic radiation comes from space. Rocks and soil, including radon, and radioactive isotopes in food and living things contribute on Earth. | Specification checked; individual official-example mapping open. |
| 6.14 · Film and GM detection | A GM tube gives pulses when radiation ionises its gas; count pulses over a measured time. Film darkens with accumulated exposure. Neither measurement alone equals the activity of every source. | May/June 2023 · 1PH0/1F · Q7(a–d) Matching scheme for that official example |
| 6.15 · Alpha, beta and gamma nature | Alpha is a helium nucleus, beta minus an electron from a nuclear transformation, and gamma electromagnetic radiation. Beta minus is not an electron escaping an outer shell. | May/June 2023 · 1PH0/1F · Q7(a–d) Matching scheme for that official example |
| 6.16 · Penetration and ionisation | Alpha is most strongly ionising and least penetrating; beta is intermediate; gamma is least ionising per unit distance and most penetrating. Energy loss through ionisation helps explain short range. | May/June 2023 · 1PH0/1F · Q7(a–d) Matching scheme for that official example |
| 6.17 · Evidence and atomic models | Most alpha particles passed through foil; rare large deflections revealed concentrated positive charge and mass. This challenged plum pudding. Bohr introduced electrons at allowed levels rather than arbitrary orbits. | Specification checked; individual official-example mapping open. |
| 6.18 · Beta minus transformation | A neutron becomes a proton and an electron is emitted. Z rises by one, changing the element; the nucleon total A is unchanged. | Specification checked; individual official-example mapping open. |
| 6.19 · Beta plus transformation | A proton becomes a neutron and a positron is emitted. A is unchanged and Z decreases by one. | May/June 2023 · 1PH0/1H · Q7(a–c) Matching scheme for that official example |
| 6.20 · Changes in A and Z | Alpha: A − 4, Z − 2. Beta minus: A unchanged, Z + 1. Beta plus: A unchanged, Z − 1. Gamma: both unchanged. Neutron: A − 1, Z unchanged. | May/June 2023 · 1PH0/1H · Q7(a–c) Matching scheme for that official example |
| 6.21 · Gamma and nuclear energy | After decay the daughter may retain excess nuclear energy. Rearrangement to a lower energy releases gamma without changing its proton or neutron counts. | Specification checked; individual official-example mapping open. |
| 6.22 · Balanced nuclear equations | For uranium-238 alpha decay, the daughter is thorium-234 with Z = 90. Check 238 = 234 + 4 and 92 = 90 + 2. Equation: ²³⁸₉₂U → ²³⁴₉₀Th + ⁴₂He. Both mass-number and charge-number totals balance. | May/June 2023 · 1PH0/1H · Q7(a–c) Matching scheme for that official example |
| 6.23 · Falling activity | As undecayed nuclei become fewer, fewer decays per second are expected. Activity falls statistically, though individual counts fluctuate. | May/June 2023 · 1PH0/1H · Q7(a–c) Matching scheme for that official example |
| 6.24 · Becquerels | One becquerel is one nuclear decay per second. A detector may register only a fraction of the emissions, so its count rate need not equal the activity. | May/June 2023 · 1PH0/1H · Q7(a–c) Matching scheme for that official example |
| 6.25 · Half-life definition | Half-life is the interval for activity, or the undecayed population, to halve. Two half-lives leave one quarter of the original population on average, not zero. | May/June 2023 · 1PH0/1F · Q4(a)(i–iii), 4(b)(i–iii) Matching scheme for that official example |
| 6.26 · Random decay, predictable populations | Individual decays are unpredictable. Relative fluctuations are smaller for a large population, making its halving pattern more dependable than that of a small sample. | Specification checked; individual official-example mapping open. |
| 6.27 · Half-life calculations and graphs | Nine hours is three half-lives: 160 → 80 → 40 → 20 Bq. On a graph, read the time interval between a value and half that value. | May/June 2023 · 1PH0/1F · Q4(a)(i–iii), 4(b)(i–iii) Matching scheme for that official example |
| 6.28P · Everyday and medical uses | Link each property to its purpose: alpha ionises air in smoke alarms; beta absorption changes with paper thickness; penetrating gamma sterilises packaged items or helps diagnose and treat disease. | May/June 2023 · 1PH0/1F · Q7(a–d) Matching scheme for that official example |
| 6.29 · Tissue damage and precautions | Ionisation can damage tissue and DNA. Shorter exposure, greater distance and suitable shielding reduce dose; preventing radioactive material entering the body reduces internal exposure. | May/June 2023 · 1PH0/1F · Q7(a–d) Matching scheme for that official example |
| 6.30P · Half-life and hazard | For equal starting numbers of nuclei, shorter half-life means greater initial activity but faster decline. Long-lived waste needs long-term containment; short-lived sources may still require shielding while highly active. | Specification checked; individual official-example mapping open. |
| 6.31 · Patient and staff precautions | Staff may have repeated exposures. Use shielding, distance, brief handling and dose monitoring. Patients should receive only the dose needed for the medical purpose. | Specification checked; individual official-example mapping open. |
| 6.32 · Contamination and irradiation | Irradiation is exposure; contamination is radioactive material on or inside something. Both can damage cells. Contamination can prolong exposure and spread; irradiation stops when exposure stops. Ordinary food irradiation leaves no radioactive source behind. | Specification checked; individual official-example mapping open. |
| 6.33P · Internal and external treatment | External radiation comes from outside the body; an internal source is placed in or near a tumour. Both can damage healthy tissue as well as cancer. Targeting limits this; an active internal source may keep exposing tissue. | May/June 2023 · 1PH0/1F · Q7(a–d) Matching scheme for that official example |
| 6.34P · Tracers and PET | A tracer follows a bodily process. In PET, emitted positrons annihilate with electrons; paired gamma photons are detected. Many events are combined to map the tracer distribution. | May/June 2023 · 1PH0/1F · Q7(a–d) Matching scheme for that official example |
| 6.35P · Nearby PET production | Short half-life makes activity fall rapidly during transport. Nearby production leaves enough activity for the scan, while limiting prolonged exposure afterwards. | Specification checked; individual official-example mapping open. |
| 6.36P · Nuclear power evaluation | Balance reliable electricity and low direct operational carbon emissions against waste, safety, construction and decommissioning costs. Consider both accident likelihood and consequences, and how public perception may differ from evidence. | Specification checked; individual official-example mapping open. |
| 6.37P · Energy from nuclear changes | Fission splits heavy nuclei, fusion joins light nuclei, and radioactive decay changes unstable nuclei. All three can release energy. | May/June 2023 · 1PH0/1H · Q10(a)(ii), 10(c) Matching scheme for that official example |
| 6.38P · Uranium-235 fission | Neutron absorption triggers U-235 fission. Two daughter nuclei, two or more neutrons and energy result. The moving products transfer energy to surrounding matter. | May/June 2023 · 1PH0/1H · Q10(a)(ii), 10(c) Matching scheme for that official example |
| 6.39P · Controlled chain reactions | A steady chain reaction averages one further fission per fission. Some emitted neutrons escape or are absorbed without causing another fission, so several emitted neutrons do not guarantee growth. | May/June 2023 · 1PH0/1H · Q10(a)(ii), 10(c) Matching scheme for that official example |
| 6.40P · Moderator and control rods | A moderator slows neutrons to increase their chance of causing U-235 fission. Control rods absorb neutrons, regulating the number available and the fission rate. | May/June 2023 · 1PH0/1H · Q10(a)(ii), 10(c) Matching scheme for that official example |
| 6.41P · Thermal energy to electricity | Fission heats coolant; thermal energy produces steam. Steam turns a turbine coupled to a generator, which supplies electricity. Some energy is dissipated to the surroundings. | Specification checked; individual official-example mapping open. |
| 6.42P · Radioactive fission products | Radioactive fission products continue decaying after the chain reaction stops. Their emissions and decay heat require appropriate containment, cooling and shielding. | Specification checked; individual official-example mapping open. |
| 6.43P · Fusion, mass and stars | Light nuclei combine into a heavier nucleus. In energy-releasing fusion the total product mass is lower, and the difference corresponds to released energy. Fusion powers stars. | Specification checked; individual official-example mapping open. |
| 6.44P · Comparing fusion and fission | Both can release nuclear energy. Fission splits a heavy nucleus and can sustain a neutron chain reaction; fusion combines light nuclei and needs conditions that bring positive nuclei very close together. | Specification checked; individual official-example mapping open. |
| 6.45P · Repulsion, temperature and pressure | Positive nuclei repel electrically. High temperature increases kinetic energy; high pressure or density increases collision frequency. At low temperature and pressure, successful close approaches are too rare. | Specification checked; individual official-example mapping open. |
| 6.46P · Practical fusion challenges | Very hot plasma is difficult to confine and loses energy. Heating, confinement and materials must support sustained reactions and economical net electricity, not merely an isolated fusion event. | Specification checked; individual official-example mapping open. |
Original mixed quiz (12 questions)
| Practice item | Original answer guidance | Related official example |
|---|---|---|
| Question 1 · 6.4 | Same protons, different neutrons | May/June 2023 · 1PH0/1H · Q7(a–c) Matching scheme for that official example |
| Question 2 · 6.18, 6.20 | A stays the same; Z increases by 1 | Specification checked; individual official-example mapping open. |
| Question 3 · 6.25, 6.27 | 20 Bq | May/June 2023 · 1PH0/1F · Q4(a)(i–iii), 4(b)(i–iii) Matching scheme for that official example |
| Question 4 · 6.12, 6.14, 6.24 | 44 counts/s | Specification checked; individual official-example mapping open. |
| Question 5 · 6.32 | Contamination | Specification checked; individual official-example mapping open. |
| Question 6 · 6.16, 6.28P | It is partly absorbed, so count rate varies with thickness | May/June 2023 · 1PH0/1F · Q7(a–d) Matching scheme for that official example |
| Question 7 · 6.39P, 6.40P | Absorb neutrons | May/June 2023 · 1PH0/1H · Q10(a)(ii), 10(c) Matching scheme for that official example |
| Question 8 · 6.10, 6.26 | No; we predict patterns for large samples | Specification checked; individual official-example mapping open. |
| Question 9 · 6.19, 6.20 | A = 18, Z = 8 | May/June 2023 · 1PH0/1H · Q7(a–c) Matching scheme for that official example |
| Question 10 · 6.25, 6.35P | Much of the isotope would decay during a long journey | Specification checked; individual official-example mapping open. |
| Question 11 · 6.17 | Atoms are mostly empty space | Specification checked; individual official-example mapping open. |
| Question 12 · 6.43P, 6.45P | To give positive nuclei enough kinetic energy to approach despite repulsion | Specification checked; individual official-example mapping open. |
Chapter explanations
| Practice item | Original answer guidance | Related official example |
|---|---|---|
| The atom & decay | See the worked explanation within this chapter. Specification points: 6.1, 6.4, 6.9, 6.10. | May/June 2023 · 1PH0/1H · Q7(a–c) Matching scheme for that official example |
| Meet the radiation | See the worked explanation within this chapter. Specification points: 6.11, 6.15, 6.16. | May/June 2023 · 1PH0/1F · Q7(a–d) Matching scheme for that official example |
| Nuclear equations | See the worked explanation within this chapter. Specification points: 6.18, 6.20, 6.22. | May/June 2023 · 1PH0/1H · Q7(a–c) Matching scheme for that official example |
| The half-life lab | See the worked explanation within this chapter. Specification points: 6.25, 6.26, 6.27. | May/June 2023 · 1PH0/1F · Q4(a)(i–iii), 4(b)(i–iii) Matching scheme for that official example |
| Detect & protect | See the worked explanation within this chapter. Specification points: 6.29, 6.32. | May/June 2023 · 1PH0/1F · Q7(a–d) Matching scheme for that official example |
| Uses & nuclear energy | See the worked explanation within this chapter. Specification points: 6.16, 6.28P, 6.34P, 6.39P, 6.40P. | May/June 2023 · 1PH0/1H · Q10(a)(ii), 10(c) Matching scheme for that official example |
| Teach it back | See the worked explanation within this chapter. Specification points: 6.1, 6.10, 6.15, 6.25, 6.28P, 6.29. | May/June 2023 · 1PH0/1F · Q7(a–d) Matching scheme for that official example |