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Nuclear Fission
- the process of splitting a large nucleus into smaller nucleus
- used as energy source to generate electricity in nuclear power plants
- When a neutron collides with the nucleus of uranium-235, the nucleus becomes uranium-236, which is highly unstable.
- The unstable nucleus splits into 2 daughter nuclei.
- 2 ~ 3 neutrons are also released during the fission process.
- Energy is released as kinetic energy by fast-moving neutrons.
- If the released neutrons collides with other uranium-235 nucleus, they can cause further fission reactions. This is called chain reaction.
The design of nuclear power plants can be found here.
Nuclear Fusion
- the process of fusing two small, light nuclei into one larger nucleus
- form of energy release in the Sun and other stars
- A common example of nuclear fusion that occurs in stars is when two isotopes of hydrogen nuclei fuse to become helium nucleus.
- There is a small amount of mass loss in the fusion reaction.
- This missing mass is converted into energy and released.
- Nuclear fusion requires fusing two positively charged nuclei. Bringing the two nuclei together will result in electrostatic repulsion.
- Nuclear fusion can only happen when enough there is enough energy to overcome the electrostatic repulsion. The process happens only in extremely high temperature and pressure.