Isotopes
Some atomic isotopes are unstable and emit radiation, they become more stable. In GCSE physics curriculum, this process is called Radioactive Decay.
Isotopes - Elements with a different number of Neutrons.
Alpha
Description: Helium nucleus of 2 protons and 2 neutrons.
Electric charge: 2+
Relative atomic mass: 4
Penetration power: Goes through plastic and stops.
Ionising effect: Big/heavy so highly ionising.
Effects of magnetic/electric field: Weakly deflected.
Beta
Description: High kinetic energy electrons.
Electric charge: 1-
Relative atomic mass: 0
Penetration power: Plastic and paper stopped by aluminium.
Ionising effect: Not a lot of mass so moderately ionising.
Effects of magnetic/electric field: Strongly deflected.
Gamma
Description: Very high frequency electromagnetic radiation.
Electric charge: 0
Relative atomic mass: 0
Penetration power: Plastic, paper, aluminium, stopped (reduced) by lead.
Ionising effect: Weakly ionising.
Effects of magnetic/electric field: Not deflected.
In GCSE physics curriculum, it is important that:
- When radiation hits an atom it can cause it to lose electrons.
- The positively charged atom produced is called an ion, this process is called ionisation.
- Radioactivity is measured in Becquerel (Bq).
End of this topic!
Drafted by Gina (Physics)