Chain Reaction
Key Stage 5
Meaning
A chain reaction is a series of reactions in which each reaction causes a further reaction.
About Chain Reactions
- In a nuclear reactor, each fission event caused by a neutron produces additional neutrons that cause further fission events.
- A steady chain reaction occurs when one fission neutron on average from each fission event produces another fission event.
- Nuclear chain reactions require a critical mass of the fissionable material.
- Chain reactions can be controlled or uncontrolled.
- Controlled chain reactions are used in nuclear reactors to generate power.
- Uncontrolled chain reactions occur in nuclear weapons.
- The ability to control the chain reaction is crucial for the safe operation of nuclear reactors.
Examples
- Uranium-235 and Plutonium-239 are materials capable of sustaining a chain reaction.
- Chain reactions are controlled in nuclear reactors to produce energy and uncontrolled in nuclear weapons for explosive effects.