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What is Uranium

Uranium (pronounced as you-Ray-nee-em) is a radioactive metal denoted by the chemical symbol Ur. It has twenty-one isotopes of which only Ur-234, Ur-235, and Ur-238 exist naturally, the last one is the most commonly known isotope with the longest half-life of 4.5×109 years, undergoing decay into thorium-234 through alpha decay or spontaneous fission. Although it is a good source of nuclear energy, there are both pros and cons of using it.

Where is it Found

It can be found in several mineral rock ore deposits reserves like brannerite, uranite, and carnotite, and also in phosphate rock and monazite sands. Its mining is done on a large scale, especially in the mines of US, resulting in a world production of about 41,000 tonnes every year. Another way of preparing the metal is by reducing uranium halides with Group 1 or Group 2 metals as well as uranium oxides with aluminum or calcium


Origin of its Name: The name has come from Uranus, the seventh planet of the solar system.

Who Discovered it: Martin Heinrich Klaproth who was a German chemist

When, Where, and How was it Discovered

In 1789, Klaproth dissolved the mineral pitchblende, collected from silver mine resources, in nitric acid. He obtained a yellow precipitate when the solution was neutralized that was suspected to be an oxide of a new element. As a result, he made an attempt to produce it by heating the precipitate with charcoal, but couldn’t succeed. In 1841, the French chemist Eugene Peligot heated uranium tetrachloride with potassium and extracted the new metal. It was later named as uranium.

Uranium Pictures


Atomic number 92 [1]
CAS number 7440-61-1 [1]
Position in the periodic table [1] Group Period Block
Actinides 7 f

Where is Uranium on the Periodic Table

Classification, Properties and Characteristics of Uranium

General Properties

Relative atomic mass 238.029 [1]
Atomic mass/weight 238.029 atomic mass units [11]
Molar mass 238.029 g/mole [12]
Mass number 238

Physical Properties

Color/physical appearance Silver with a greenish tinge [1]
Odor Unknown [13]
Melting point/freezing point 1135°C (2075°F) [1]
Boiling point 4131°C (7468°F)  [1]
Density 19.1 g/cm3 [1]
Standard state (normal phase) at room temperature (solid/liquid/gas) Solid [1]
Hardness 6 Mohs [14]
Thermal conductivity 27.5 W m-1 K-1 [3]

Chemical Properties

Flammability Unknown[13]
Oxidation state/Oxidation number (+2), +3, +4, +5, +6 [1]

Atomic Data of Uranium (Element 92)

Valence electrons 6 [15]
Electron configuration (noble gas configuration) [Rn] 5f36d17s2[1]
Atomic structure [4]
– Number of electrons 92
– Number of neutrons 146
– Number of protons 92
Radius of atom
– Atomic radius 2.41 Å [1]
– Covalent radius 1.83 Å [1]
Ion charge +3 [16]
Ionization energy [1]


1st 2nd 3rd 4th 5th 6th 7th
597.64 1022.7

Uranium Atomic Structure (Bohr Model)

What are the Commercial Uses of Uranium

  • Raw uranium traded as yellowcake is mainly used in the preparation of non-renewable fossil fuel rods for generating electricity at nuclear power plants [1, 5].
  • Ur glasses are sometimes used in the making of decanters, marbles, and vases. However, due to its radioactive properties, the manufacturing of the glasses have been restricted.
  • In the ammunition industry, the depleted uranium is used in bullets and shells.
  • Uranium-lead dating method required in geological age-determination is based on the fact that Pb accumulates in Ur minerals as per the known radioactive decay rates of the parent isotopes [4].
  • The nitrate of the element, uranium nitricum is useful in the treatment of diabetes, hypertension, and edema [6].

Uranium Rod

Does it Have Any Toxic Effects on Humans

Long-term exposure to its radiations has been linked to respiratory ailments and renal toxicity. When inhaled or ingested in excess, it causes lung and kidney failure as a result of acute poisoning[7].

Interesting Facts

  • Refined or enriched uranium higher contentment used in the making of high-grade weapons comprises a higher percentage of Ur-235 that is extracted with a gas centrifuge from the pure element [8].
  • Uranium bomb named as ‘Little Boy ‘was one of the atomic bombs dropped on Hiroshima, Japan during the World War 2 [9].
  • It is believed to have formed from a supernova explosion in the universe [10].


Uranium Price

The cost of the pure metal may vary between $33 and $35 per pound.

Uranium Ore



One response to “Uranium”

  1. James says:

    Very helpful for learners

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