Page 46 - Curriculum Visions Dynamic Book

Uranium (U)
Element 92.The best-known element in the actinide series in the Periodic Table associated with radioactivity.
Uranium is a dense, hard, silvery- white metal that can easily be shaped.
During the 1930s it was realised that uranium could be bombarded by slow neutrons and so cause a chain reaction leading to a nuclear explosion.That is the basis of the atomic bomb.
 A uranium billet for reprocessing.
Discovery
It was discovered in Germany in 1789 by Martin Heinrich Klaproth.Although it was discovered in the 18th century, it was not until 1896 that the French physicist Henri Becquerel discovered that uranium was radioactive.
Technology
Its main use is as a nuclear fuel because a kilogram of uranium produces the same energy as three million kilograms of coal. It can be converted into plutonium in ‘breeder’ reactors. It is also used in nuclear bombs.
Geology
The most important uranium ore is uranite, usually called pitchblende, UO2. Most of the Earth’s internal heat is probably caused by nuclear reactions of uranium (and thorium).
Biology
Uranium does not occur in living things. It is now found in small concentrations in places where nuclear explosions or leaks have occurred. Uranium is radioactive and is therefore a radiation hazard.
Key facts...
Name: uranium
Symbol: U
Atomic number: 92
Atomic weight: 238
Position in Periodic Table: inner transition
metal; period 6 (actinide series)
State at room temperature: solid
Colour: silvery-white
Density of solid: 19.05 g/cc
Melting point: 1,132.3°C
Boiling point: 3,818°C
Origin of name: named after the planet Uranus,
which had recently been discovered
Shell pattern of electrons: 2–8–18–32–21–9–2
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