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Band of Stability

Band of Stability

Hazard Sign - ExplosiveIntroduction: On April 26, 1986, a nuclear disaster occurred near the Chernobyl Nuclear Power Plant in Ukraine, causing one of the worst nuclear power plant accidents in history and resulting in massive costs and a large number of casualties. At the heart of this disaster was a lack of safety protocols and design deficiencies, as well as the fact that the nuclides used in this nuclear power plant were highly unstable. When radioactive nuclides are highly unstable, they release the products of a process known as fission, or the splitting of a radioactive nuclide into two or more less massive products.

The products of fission from the Chernobyl power plant included iodine-131 and cesium-137, which was responsible for the radiation exposure received by the residents of the areas surrounding the power plant. Radioactive nuclides in nuclear power plants were highly unstable in the first place because the ratio of neutrons to protons was too high. This idea of a nucleus being stable or unstable relates to what is known as the band of stability. Specifically, when the ratio of neutrons to protons is between 1:1 and 1.5:1, the nuclide is stable and generally won't break down. However, when the ratio of neutrons to protons is greater than 1.5:1, the nuclide is unstable and tends to break down.

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