Key learning points

1. Nuclear fission is the splitting of a large and unstable nucleus such as uranium or plutonium.
2. A neutron fired at a uranium nucleus can cause nuclear fission that splits the nucleus and emits 2 or 3 more neutrons.
3. The motion of all the particles shot out from a nuclear fission can cause heating by making other particles move faster.
4. Neutrons shot out from a nuclear fission can split more uranium nuclei in a chain reaction.
5. Nuclear fusion is the joining of two light nuclei to form a heavier nucleus with the creation of gamma radiation.

Keywords

• Nuclear fission - the splitting of large nuclei to form pairs of smaller nuclei and some free neutrons, with the release of energy

• Daughter nuclei - the smaller nuclei produced during nuclear fission

• Chain reaction - a series of nuclear fission events, with each one triggered by a neutron from a previous nuclear fission

• Nuclear fusion - the combining of small nuclei at very high temperatures with the release of energy

Common misconception