GCSE Physics - Alpha, Beta and Gamma Radiation #33

Isotopes: Different forms of elements that have the same number of protons but different numbers of neutrons.
Stability of Isotopes: Only one or two of an element’s isotopes are stable. The rest are unstable and can undergo radioactive decay.
Radioactive Materials: Consist of unstable isotopes that can decay by emitting radiation.

Alpha Radiation
- Alpha Particles: Composed of two protons and two neutrons; essentially the same as a helium nucleus (represented as He).
- Charge: Have an overall charge of +2 due to the two protons and no electrons.
- Penetration:
  - Easily stopped by collisions with other molecules.
  - Can travel a few centimeters in air.
  - Absorbed by a single sheet of paper.
- Ionization: Very strongly ionizing; can knock electrons off atoms easily.
Beta Radiation
- Beta Particles: Essentially electrons with a charge of -1 and negligible mass.
- Emission: Emanate when a neutron in an atom decays into a proton and an electron; the proton stays in the nucleus.
- Penetration:
  - Moderately ionizing.
  - Can travel several meters in air or require about five millimeters of aluminum to stop.
Gamma Radiation
- Gamma Rays: Waves of electromagnetic radiation (unlike alpha and beta particles).
- Emission: Often released after alpha or beta radiation as the nucleus releases extra energy.
- Charge and Mass: Massless and uncharged, allowing them to pass through materials.
- Penetration:
  - Weakly ionizing.
  - Can travel long distances in air.
  - Requires thick sheets of lead or several meters of concrete to stop.
Neutron Emission
- If a nucleus has too many neutrons, it may emit one to restore stability.