Nuclear Fission
Definition and meaning of Nuclear Fission in chemistry.
Nuclear fission is a radioactive decay process in which the nucleus of a heavy, unstable atom splits into two or more smaller, lighter nuclei. This splitting action is accompanied by the release of a massive amount of energy and often several free neutrons.
In more detail
Fission can occasionally occur spontaneously in some heavy isotopes, but it is much more typically induced by bombarding a fissile nucleus with a free neutron. When the nucleus absorbs the neutron, it becomes highly unstable and rapidly fractures into separate pieces. The new free neutrons released during this split can then strike other nearby heavy nuclei, potentially triggering a massive self-sustaining chain reaction if enough fissile material is present.
Key facts
| Field | Physical Chemistry |
|---|---|
| Process | Splitting of a heavy atomic nucleus |
| Byproducts | Lighter nuclei, free neutrons, and energy |
The bombardment of uranium-235 with a slow-moving neutron causes it to split into barium-141 and krypton-92, releasing three free neutrons and significant thermal energy.
Frequently asked questions
What is a nuclear chain reaction?
A chain reaction occurs when the neutrons released by one fission event trigger fission in other nuclei, sustaining the reaction continuously.