Radioactivity & Particles · 2 question types
Past paper frequency (2018 to 2024)
This topic accounts for approximately 8% of your exam marks.
Properties of alpha, beta and gamma radiation and nuclear equations tested consistently.
| Radiation | Symbol | Nature | Charge | Relative mass |
|---|---|---|---|---|
| Alpha | α (⁴₂He) | Two protons + two neutrons (a helium nucleus) | +2 | 4 |
| Beta | β⁻ (⁰₋₁e) | A high-speed electron ejected from the nucleus | −1 | 1/2000 (negligible) |
| Gamma | γ | A high-energy electromagnetic wave (photon) | 0 | 0 |
