Build the nuclear model
The nucleus contains protons and neutrons; electrons occupy regions around it. Isotopes have the same number of protons but different numbers of neutrons. Mass number counts nucleons, while atomic number counts protons.
GCSE Physics resources
AQA GCSE Atomic structure
AQA GCSE Atomic structure Revision
Atomic-structure questions combine a model of the atom, radiation properties and careful use of nuclear notation. Always distinguish irradiation from contamination.
Topic overview
Plan your atomic structure revision
Use the resource cards below to revise one idea at a time. Each page includes worked examples, mini quizzes, practice questions, exam language and a visual or simulation when it adds learning value.
Knowledge map
How the topic fits together
Use this overview to find the part of the topic that needs attention; the focused guides below teach and assess each idea in depth.
Compare the three radiations
Alpha is strongly ionising with a short range. Beta is moderately ionising with a medium range. Gamma is weakly ionising and highly penetrating. The exact choice of radiation depends on the application.
Use half-life safely
Half-life is the time for the activity or count rate of a sample to fall to half its value. Radioactive decay is random for individual nuclei, but the pattern is predictable for a large sample.
Focused revision
Choose one idea at a time
Each guide combines explanation, a diagnostic check, misconception repair, worked examples and exam-style practice.
AT-01
Atoms, Isotopes and Nuclear Notation
Atomic notation counts particles; scattering evidence explains why those particles are arranged in a tiny nucleus rather than spread through the atom.
AT-02
Alpha, Beta and Gamma Radiation
Radiation changes an unstable nucleus. Identify what is emitted, how it interacts with matter and how the nuclear numbers must balance.
AT-03
Half-Life and Radioactive Decay
Activity belongs to the source; count rate belongs to the detector. Correct the latter for background before interpreting the source’s decay pattern.
AT-04
Radiation Hazards, Contamination and Irradiation
A sealed source outside the body and radioactive material inside the body require different controls. Both can cause irradiation, but only one involves contamination.
NEW-NUCLEAR
Nuclear Fission, Chain Reactions and Fusion
Fission splits a heavy nucleus; fusion joins light nuclei. Both can release nuclear energy, but their requirements and control mechanisms differ.
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AQA GCSE Physics Required PracticalsLearn the method, diagnose errors and practise it.GCSE Physics Equations and Maths SkillsLearn the method, diagnose errors and practise it.How to Answer GCSE Physics Calculation QuestionsLearn the method, diagnose errors and practise it.How to Answer GCSE Physics Six-Mark QuestionsLearn the method, diagnose errors and practise it.GCSE Physics Graph SkillsLearn the method, diagnose errors and practise it.
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Continue from Atomic structure
AQA GCSE Physics Half-Life and Decay Graphs WorksheetFree printable questions and a separate solutions PDF.
AQA GCSE Physics Atomic Structure, Nuclear Equations and Radiation WorksheetFree printable questions and a separate solutions PDF.
AQA GCSE Physics Alpha Beta Gamma Penetration and Shielding WorksheetFree printable questions and a separate solutions PDF.
AQA GCSE Physics Radiation in Medicine Uses Risks and Half Life WorksheetFree printable questions and a separate solutions PDF.
AQA GCSE Physics Nuclear Fission Fusion and Chain Reactions WorksheetFree printable questions and a separate solutions PDF.
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