Nuclear fission and fusion

Nuclear fission process

Neutron is absorbed by a nucleus

Nucleus splits into two parts

Neutrons are released

And gamma rays are emitted

neutrons may go on to start a chain reaction

Nuclear fission is

the splitting of a large and unstable nucleus (eg uranium or plutonium)

For fission to occur

An unstable nucleus must absorb a slow moving neutron

The explosion caused by a nuclear weapon is caused by

an uncontrolled chain reaction.

Nuclear fusion

the joining of two light nuclei to form a heavier nucleus. Some of the mass may be converted into energy of radiation