Urankjerner

Urankjerner refers to the atomic nuclei of the element uranium. Uranium is a chemical element with the symbol U and atomic number 92. Its nucleus is composed of protons and neutrons. Naturally occurring uranium is primarily a mixture of two isotopes: uranium-238 (238U), which makes up about 99.3% of the total, and uranium-235 (235U), accounting for about 0.7%.

Uranium nuclei are notable for their radioactivity. Uranium-238 undergoes alpha decay with a very long half-life, eventually decaying through a series of other radioactive elements into stable lead. Uranium-235 is also radioactive, but its significance lies in its fissile nature. This means that when a uranium-235 nucleus absorbs a slow-moving neutron, it can split into two smaller nuclei, releasing a significant amount of energy and more neutrons. This process is called nuclear fission.

The fission of uranium-235 is the principle behind nuclear power generation and nuclear weapons. In nuclear reactors, a controlled chain reaction of uranium-235 fission is sustained to produce heat, which is then used to generate electricity. In nuclear weapons, an uncontrolled, rapid chain reaction of fissioning uranium-235 releases a massive amount of energy very quickly. Enriched uranium, which has a higher concentration of the fissile uranium-235 isotope, is required for both of these applications.

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