Nuclear Fission and Fusion

In some elements, the nucleus is large and unstable

In nuclear fission, the nucleus of these elements splits

1. When the element absorbs a neutron, it triggers the nucleus to split (fission)

2. It then forms 2 smaller nuclei, roughly equal in size (daughter nuclei). It also emits two or three neutrons + gamma radiation. Energy is also released

The neutrons can be absorbed by more nuclei and cause fission (chain reaction)

A controlled chain reaction is used to release energy in a nuclear reactor.

The explosion in a nuclear weapon is caused by an uncontrolled fission chain reaction.

In nuclear fusion, two light nuclei are joined together to form a heavier nucleus

Some of the mass of nuclei can be converted into energy, which is released as radiation