CP6-2 Radioactivity

3. A nucleus that will decay and give out ionising radiation.
5. The time taken for half of the radioactive nuclei in a sample of radioactive material to have decayed.
6. An atom or group of atoms with an electrical charge due to the gain or loss of electrons.
9. A high-frequency electromagnetic wave emitted from the nucleus of a radioactive atom.
10. An unwanted addition that makes something unsuitable or impure
12. The units for the activity of a radioactive object. One becquerel is one radioactive decay per second.
14. Any process that cannot be predicted and can happen at any time.
15. When an unstable nucleus changes by giving out ionising radiation to become more stable.
16. The number of alpha or beta particles or gamma rays detected by a Geiger–Müller tube in a certain time.

1. A device that can detect ionising radiation and is used to measure the activity of a radioactive source.
2. A change to the DNA instructions in a cell.
4. The likelihood of an event happening.
7. Ionising radiation in the environment, naturally occurring and also man-made.
8. The amount received at one time – for example, the amount of radiation a person receives.
11. Something exposed to ionising radiation.
13. Charged particles with a high energy that come from stars, neutron stars, black holes and supernovae.