Nuclear fission

Definition

Nuclear fission is the process in which a nucleus of a heavy atom splits into two or more smaller nuclei, along with the release of energy. This reaction is often initiated by the absorption of a neutron.

5 Must Know Facts For Your Next Test

1. The most commonly used materials for nuclear fission are Uranium-235 and Plutonium-239.
2. Nuclear fission releases a significant amount of energy, which is utilized in nuclear power plants to generate electricity.
3. In medical applications, nuclear fission can be used to produce isotopes for diagnostic imaging and cancer treatment.
4. Fission reactions produce not only smaller nuclei but also free neutrons, which can induce further fission reactions, creating a chain reaction.
5. The concept of critical mass is crucial; it refers to the minimum amount of fissile material needed to maintain a self-sustaining chain reaction.

Review Questions

• What are two common isotopes used in nuclear fission?
• How is the energy released from nuclear fission typically harnessed in power plants?
• What role do free neutrons play in sustaining a nuclear fission chain reaction?

Related terms

Chain Reaction:

A series of reactions where a reactive product or by-product causes additional reactions to take place.

Critical Mass:

The minimum quantity of fissile material needed to sustain a nuclear chain reaction.

Neutron Moderation: The process of slowing down fast neutrons so that they are more likely to cause fission when they collide with fissile nuclei.