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Citizen Kurchatov: Stalin's Bomb Maker



Although theorized earlier, plutonium was an unknown element to scientists until it was discovered in 1941 in America. It was unknown before because there is only a small amount in nature. In fact, it wasn't discovered in nature -- it was produced in a laboratory.

Plutonium-239 is created by bombarding uranium-238 with protons. When an extra proton is captured by a uranium-238 nucleus, plutonium-239 is created.

Plutonium-239, used in bombs and industrial applications, is produced in production reactors. Uranium-238 is exposed to a proton source and transmuted into plutonium. The plutonium is then extracted and separated in a plutonium purification plant.

Plutonium was preferred over uranium for atomic bombs because it is a more efficient fissionable fuel. A smaller amount of plutonium is needed for critical mass than for uranium.       

Related Web Sites

What is Plutonium?
Amarillo National Resource Center for Plutonium


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