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4. Atomic structure

Atoms and isotopes

2 lessons
4.1 The structure of the atom and isotopes The structure of the atom, the size of atoms and nuclei, atomic number, mass number, isotopes and ions, and how electrons move between energy levels when they absorb or emit radiation. AQA Edexcel OCR 4.2 Developing the model of the atom How the model of the atom developed from the plum pudding model to the nuclear model, the alpha scattering experiment, Bohr's energy levels and the discovery of the neutron. AQA Edexcel OCR

Radioactive decay

5 lessons
4.3 Alpha, beta and gamma radiation Radioactive decay, activity and count rate, and the nature, penetration and ionising power of alpha, beta, gamma radiation (and positrons for Edexcel). AQA Edexcel OCR 4.4 Background radiation and detecting radiation Natural and man-made sources of background radiation, radiation dose in sieverts, detecting radiation with a Geiger-Müller tube and photographic film, and correcting a count for background. AQA Edexcel 4.5 Nuclear equations How to write and balance nuclear equations for alpha decay, beta decay, gamma emission and (for Edexcel) positron emission. AQA Edexcel OCR 4.6 Half-life Half-life as the time for the activity or number of nuclei to halve, reading it from a decay curve, calculating activity after a number of half-lives, and the net decline as a ratio. AQA Edexcel OCR 4.7 Contamination and irradiation The difference between irradiation and contamination, which types of radiation are most dangerous outside and inside the body, precautions for working with radioactive sources, and why peer review matters. AQA Edexcel OCR

Uses of nuclear radiation and nuclear energy

3 lessons
4.8 Uses and hazards of nuclear radiation How the type of radiation and the half-life of an isotope decide its use: medical tracers, radiotherapy, sterilising, smoke alarms and PET scans, and the hazards that must be managed. For Separate Science. Separate only AQA Edexcel OCR 4.9 Nuclear fission How nuclear fission releases energy, how a chain reaction is started and controlled in a nuclear reactor, and the advantages and disadvantages of nuclear power. For Separate Science. Separate only AQA Edexcel OCR 4.10 Nuclear fusion How light nuclei join in nuclear fusion, why fusion needs extremely high temperature and pressure, fusion in stars and the difficulties of fusion power. For Separate Science. Separate only AQA Edexcel OCR