Uranium (play / jʊˈreɪniəm / yew-RAY-nee-?m) is a silvery-white metallic chemical element in the actinide series of the periodic table with atomic number 92. It is assigned the chemical symbol U. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. The uranium nucleus binds between 141 and 146 neutrons, establishing six isotopes, the most common of which are U-238 (146 neutrons) and U-235 (143 neutrons). All isotopes are unstable and uranium is weakly radioactive. Uranium has the second highest atomic weight of the naturally occurring elements, lighter only than plutonium-244.[3] Its density is about 70% higher than that of lead, but not as dense as gold or tungsten. It occurs naturally in low concentrations of a few parts per million in soil, rock and water, and is commercially extracted from uranium-bearing minerals such as uraninite.
In nature, uranium is found as uranium-238 (99.2742%), uranium-235 (0.7204%), and a very small amount of uranium-234 (0.0054%). Uranium decays slowly by emitting an alpha particle. The half-life of uranium-238 is about 4.47 billion years and that of uranium-235 is 704 million years,[4] making them useful in dating the age of the Earth.
Many contemporary uses of uranium exploit its unique nuclear properties. Uranium-235 has the distinction of being the only naturally occurring fissile isotope. Uranium-238 is fissionable by fast neutrons, and is fertile, meaning it can be transmuted to fissile plutonium-239 in a nuclear reactor. Another fissile isotope, uranium-233, can be produced from natural thorium and is also important in nuclear technology. While uranium-238 has a small probability for spontaneous fission or even induced fission with fast neutrons, uranium-235 and to a lesser degree uranium-233 have a much higher fission cross-section for slow neutrons. In sufficient concentration, these isotopes maintain a sustained nuclear chain reaction. This generates the heat in nuclear power reactors, and produces the fissile material for nuclear weapons. Depleted uranium (U-238) is used in kinetic energy penetrators and armor plating.[5The price of Uranium is climbing. Although the U.S. is the largest generator of nuclear power, at approximately 30% of worldwide nuclear generation, a reactor hasn’t been built in decades. Why is uranium on the move, now at a spot price of around $73? The answer is in the developing countries, particularly China and India.
China is pursuing uranium more aggressively than ever. A typical 1000 megawatt nuclear reactor provides enough electricity to power a modern city of up to one million people, making it an attractive option for a country with a population of over 1.3 billion people. In the last year alone they have more than tripled their uranium imports, put two reactors online, and are not stopping there as Beijing has plans to build many more.
India is the other major player in the uranium market as Asia’s third largest energy consumer. It is estimated that their need for uranium will increase 10 fold by 2020, with a consumption of about 8,000 tonnes annually. They are opening domestic numerous uranium mines this year, and have signed civil nuclear agreements in six countries.
With these predicted astronomical numbers for China and India, speculation is driving the market. The price spike in 2007 was similar in that it was driven by sentiment, but very different because only a small amount of uranium actually changed hands.
When speculators see China’s commitment to invest $511 billion in nuclear energy combined with India’s long-term demand, it wouldn’t be surprising to see them running back to uranium this year.
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