Radiation

3. Type of radiation which is most ionising (damaging)
5. Type of radiation which can travel up to 1 metre in air
6. The ……… number is number of protons in the nucleus of an atom.
8. What do unstable nuclei emit (give out)?
12. What have a radius of about 1 × 10-10 metres?
13. Where are the protons and neutrons found in an atom?
14. Radioactive decay is a ……. process because you can’t tell which nucleus will decay next.
15. An alpha particles consists of two protons and two…?

1. The time taken for half of the unstable nuclei of a radioactive isotope to decay.
2. A beta particle is a high speed…?
4. Type of radiation which stopped by several centimetres of lead or thick concrete
7. The ……… number is the number of protons and neutrons in the nucleus of an atom.
9. An atom which has lost (or gained) electrons.
10. Atoms with the same number of protons.
11. Atoms with the same number of protons (same element) but different number of neutrons.