Radioactivity

Atoms are made up of protons, neutrons and electrons. Change the number of neutrons in an atom and it becomes an isotope, change the number of electrons, it becomes an ion.

With the wrong number of neutrons, nuclei can fall apart. A nucleus will regain stability by emitting alpha or beta particles and then 'cool down' by emitting gamma radiation.

People are exposed to sources of radiation in all aspects of everyday life. Radioactive sources can be very useful but need handling carefully to ensure safety.

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