Nuclear radiation

3. a fast moving helium nucleus emitted by an unstable nucleus
6. A common radioactive source found in most houses
8. ionizing radiation that is naturally present in the environment
9. a radioisotope that is injected into the body
12. a radioactive isotope
13. can block alpha particles
16. one of the factors that can reduce the risk of exposure to nuclear radiation
18. discovered radium
22. changes during some types of radiactive decay
23. a fast moving electron emitted by an unstable nucleus
24. a type of electromagnetic radiation
26. mass number of an unstable carbon isotope
27. a metal that can be used to shield from nuclear radiation

1. the use of nuclear radiation to treat disease
2. The emission of radiation (particles and energy) from atoms
4. two or more types of atoms that have the same number of protons but have different numbers of neutrons in their nuclei.
5. site of one of the worst nuclear accidents
7. the number used to identify an isotope e.g. U-235
10. a disease that can be caused by nuclear radiation
11. The time it takes for half of the atoms in the original sample of a radioisotope to decay
14. the emission or transmission of energy in the form of waves or particles
15. can block beta particles
17. radiation , the radiation (particles and energy) emitted from an unstable nucleus (alpha particles, beta particles or gamma rays).
19. Substances that release nuclear radiation
20. the process by which an unstable atomic nucleus loses energy by emitting nuclear radiation.
21. change to a DNA molecule
25. A device that can detect ionising radiation (nuclear radiation)