Nuclear Concepts: Radioactivity
30 lessons, pages 1471–1500.
- Nuclear Change Versus Chemical Change — Changes in the nucleus compared with electron rearrangement
- Nuclide Symbols and Nuclear Counting — Atomic number, mass number and neutron count revisited
- Stable and Unstable Nuclides — Why some nuclei transform spontaneously
- What Radioactivity Means — Spontaneous nuclear transformation and emitted radiation
- Alpha Particles and Alpha Decay — Helium nuclei, mass-number change and charge balance
- Beta-Minus Emission — Neutron-to-proton conversion and electron emission
- Beta-Plus Emission — Proton-to-neutron conversion and positron emission
- Electron Capture — Inner-electron capture and atomic-number change
- Gamma Radiation from Nuclear Excitation — Energy emission without changing Z or A
- Comparing Alpha, Beta and Gamma — Particle identity, charge, penetration and shielding trends
- Balancing Nuclear Equations — Conserving mass number and electric charge
- Decay Chains and Daughter Nuclides — Following sequential transformations without skipping steps
- Activity as Decays per Second — Using the becquerel and distinguishing activity from dose
- The Meaning of Half-Life — Time for an expected undecayed population to halve
- Repeated Half-Life Calculations — Successive halving of nuclei, mass and activity
- Exponential Decay and Decay Constant — Connecting N, lambda and half-life at an introductory level
- Half-Life Graphs — Reading time and remaining fraction from a decay curve
- Why Half-Life Is Statistical — Unpredictable individual events and predictable large populations
- Background Radiation and Measurement — Sources, counting variation and background subtraction
- Detection of Ionising Radiation — What a detector counts and why count rate differs from activity
- Ionisation and Matter — How emitted radiation can remove electrons from atoms
- Irradiation and Contamination — Exposure to a source versus radioactive material transfer
- Distance, Time and Shielding — Qualitative ways exposure changes with geometry and barriers
- Medical Tracers — Selecting an isotope by detection route and practical half-life
- Radiotherapy and Nuclear Medicine — Distinguishing imaging, treatment and dose control
- Radiometric Dating Basics — Parent–daughter change and half-life assumptions
- Carbon-14 Dating and Its Scope — Organic material, exchange while living and age estimation
- Nuclear Fission as a Chain Process — Neutron-induced splitting, energy and further neutrons
- Nuclear Fusion and Stellar Energy — Light nuclei combining under extreme conditions
- Radioactivity: Integrated Review — Linking symbols, decay equations, half-life and applications