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Uranium (U): Fun Facts and Information About the Element

What is the symbol? U
What is the atomic number? 92
What is the atomic weight? 238.0289
What is the melting point in Celsius? 1132
What is the boiling point in Celsius? 3818
What is the density (g/cm3)? 18.95
What year was it discovered? 1789
Who discovered the element? Martin Heinrich Klaproth
What group is the element in? 102
What is the electron configuration? [Rn] 5f3 6d1 7s2
What is the ionization energy? 6.1941
What element category is it in? Actinoids

Where is Uranium Found?

Uranium, not as rare as once thought, is now considered to be more plentiful than mercury, antimony, silver, or cadmium, and is about as abundant as molybdenum or arsenic. It occurs in numerous minerals such as pitchblende, uraninite, carnotite, autunite, uranophane, and tobernite. It is also found in phosphate rock, lignite, monazite sands, and can be recovered commercially from these sources.

Uranium can be prepared by reducing uranium halides with alkali or alkaline earth metals or by reducing uranium oxides by calcium, aluminum, or carbon at high temperatures. The metal can also be produced by electrolysis of KUF5 or UF4, dissolved in a molten mixture of CaCl2 and NaCl. High-purity uranium can be prepared by the thermal decomposition of uranium halides on a hot filament.

What is Uranium Used For?

Uranium is used in inertial guidance devices, in gyro compasses, as counterweights for aircraft control surfaces, as ballast for missile reentry vehicles, and as a shielding material. Uranium metal is used for X-ray targets for production of high-energy X-rays.

Natural uranium, enriched with 235U by a small percentage, is used to fuel nuclear power reactors to generate electricity. One pound of completely fissioned uranium has the fuel value of over 1500 tons of coal.

The uses of nuclear fuels to generate electrical power, to make isotopes for peaceful purposes, and to make explosives are well known. The estimated world-wide capacity of the 429 nuclear power reactors in operation in January 1990 amounted to about 311,000 megawatts.