Because uranium is primarily an alpha-emitter, its radioactivity only really becomes a problem if it gets inside the body, where it can accumulate in the kidneys, causing damage.
However, uranium is also a heavy metal, and its chemical toxicity is of greater importance - it is approximately as toxic as lead or mercury. But uranium doesn't deserve it's image as one of the periodic table's nasties.
Much of the internal heat of the earth is considered to be due to the decay of natural uranium and thorium deposits. Perhaps those looking to improve the public image of nuclear power should demand the relabelling of geothermal ground-source heat pumps as nuclear? The reputation of this element would also be significantly better if only uranium glass was the element's most publicly known face. In the same way that lead salts are added to glass to make sparkling crystal glassware, uranyl salts give a very beautiful and translucent yellow-green colour to glass, although glassmakers have experimented to produce a wide range of gem-like colours.
An archaeological dig near Naples in unearthed a small green mosaic tile dated back to 79 AD, which was reported to contain uranium, but these claims have not been verified. However in the early th and early 20 th century it was used widely in containers and wine-glasses. If you think that you own a piece, you can check with a Geiger counter, or by looking for the characteristic green fluorescence of the uranium when held under a UV-lamp. Pieces are generally regarded as safe to drink from, but you are advised not to drill holes in them, or wear them.
Fair enough. Or inadvertently eating it too, presumably. That was Edinburgh University chemist Polly Arnold explaining the softer side of the armour piercing element Uranium. Next week Andrea Sella will be introducing us to some crystals with intriguing properties. You HAVE to see this. He beckoned me into a hallway. As the crystals caught the light from the new fluorescent lights hanging from the ceiling, the pink colour seemed to deepen and brighten up.
We moved the crystals back into the sunlight and the colour faded again, and moving the crystals back and forth they glowed and dimmed in magical fashion.
But what did they contain? Well, the answer's Erbium and you can hear all about it in next week's Chemistry in its element. I'm Chris Smith, thank you for listening and goodbye. Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists. There's more information and other episodes of Chemistry in its element on our website at chemistryworld. Click here to view videos about Uranium. View videos about.
Help Text. Learn Chemistry : Your single route to hundreds of free-to-access chemistry teaching resources. We hope that you enjoy your visit to this Site. We welcome your feedback. Data W. Haynes, ed. Version 1. Coursey, D. Schwab, J. Tsai, and R. Dragoset, Atomic Weights and Isotopic Compositions version 4. Periodic Table of Videos , accessed December Podcasts Produced by The Naked Scientists. Download our free Periodic Table app for mobile phones and tablets.
Explore all elements. D Dysprosium Dubnium Darmstadtium. E Europium Erbium Einsteinium. F Fluorine Francium Fermium Flerovium.
G Gallium Germanium Gadolinium Gold. I Iron Indium Iodine Iridium. K Krypton. O Oxygen Osmium Oganesson. U Uranium. V Vanadium. X Xenon. Y Yttrium Ytterbium. Z Zinc Zirconium. Membership Become a member Connect with others Supporting individuals Supporting organisations Manage my membership.
Facebook Twitter LinkedIn Youtube. Discovery date. Discovered by. Martin Heinrich Klaproth. Origin of the name. Uranium was named after the planet Uranus.
Melting point. Boiling point. Atomic number. Relative atomic mass. Key isotopes. Electron configuration. CAS number. ChemSpider ID. ChemSpider is a free chemical structure database. Electronegativity Pauling scale. Common oxidation states.
Atomic mass. Half life. Mode of decay. Relative supply risk. Crustal abundance ppm. Top 3 producers. Top 3 reserve holders. Political stability of top producer. Political stability of top reserve holder. Young's modulus GPa. Shear modulus GPa. Bulk modulus GPa.
Vapour pressure. Temperature K. It occurs in numerous natural minerals such as pitchblende, uraninite, carnotite, autunite, uranophane, and tobernite. It is also found in phosphate rocks, lignite, monazite sands, and is recovered commercially from these sources.
This incentive program has greatly increased the known uranium reserves. Pure uranium is a silvery white, weakly radioactive metal, which is harder than most elements.
It is malleable, ductile, slightly paramagnetic, strongly electropositive and is a poor electrical conductor. Uranium is pyrophoric when finely divided. It is a little softer than steel and is attacked by cold water in a finely divided state.
In air, uranium metal becomes coated with a layer of oxide. Uranium metal is unaffected by alkalis. Uranium metal 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. High-purity uranium can be prepared by the thermal decomposition of uranium halides on a hot filament. Uranium metal reacts with almost all nonmetallic elements and their compounds , with reactivity increasing with temperature.
Hydrochloric and nitric acids dissolve uranium, but non-oxidizing acids other than hydrochloric acid attack the element very slowly. When finely divided, it can react with cold water. In air, uranium metal oxidizes and becomes coated with a dark layer of uranium oxide. Uranium forms a variety of alloys and compounds with the most important oxidation states being uranium IV and uranium VI , and their two corresponding oxides are, respectively, uranium dioxide , UO 2 and uranium trioxide , UO 3.
Besides the oxides, other Important uranium compounds include fluorides, chlorides, bromides, iodides, carbonates, hydrides, carbides, nitrides, phosphates, etc.
At room temperatures, uranium hexafluoride, UF 6 , has a high vapor pressure , making it useful in the gaseous diffusion process used to separate the rare U from the common U isotope. Uranium hydrides, nitrides and carbides are relatively inert semimetallic compounds that are minimally soluble in acids and have been used as stable fuel pellets in nuclear power reactor technology.
Uranium was used in as coloring agents in ceramic glazes and glass in ancient Rome and in the Middle Ages producing orange-red to lemon yellow hues. Many contemporary uses of uranium exploit its unique nuclear properties. Uranium has the distinction of being the only naturally occurring fissile isotope. This means it can be split into two or three fragments fission products by thermal neutrons. Uranium is fissionable by fast neutrons, and is fertile , meaning it can be transmuted to fissile plutonium in a nuclear reactor.
Another fissile isotope, uranium , can be produced from natural thorium and is also important in nuclear technology. While uranium has a small probability for spontaneous fission or even induced fission with fast neutrons, uranium and to a lesser degree uranium 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. This nuclear conversion can be brought about in breeder reactors where it is possible to produce more new fissionable material than the fissionable material used in maintaining the chain reaction.
Depleted uranium U depleted of uranium is used in balistic armor penetration and as armor plating. Uranium has a half-life of about 23 minutes and decays into neptunium through beta decay. Neptunium has a half-life of about 2. Although it does not occur naturally, uranium is also a fissionable material that can be used as a fuel in nuclear reactors. To produce uranium, atoms of thorium are exposed to neutrons. Thorium forms when thorium absorbs a neutron.
Thorium has a half-life of about 22 minutes and decays into protactinium through beta decay. Protactinium has a half-life of about 27 days and decays into uranium, also through beta decay. If completely fissioned, one pound 0. Uranium is a dense metal that has uses outside of the nuclear power industry. It is used as a target for X-ray production, as ammunition for some types of military weaponry, as a shield against radiation, as a counterweight for aircraft control surfaces and in the gyroscopes of inertial guidance systems.
Uranium compounds have been used for centuries to color glass. A 2, year old sample of yellow glass found near Naples, Italy contains uranium oxide. Uranium trioxide UO 3 is an orange powder and has been used in the manufacture of Fiestaware plates. Other uranium compounds have also been used to make vaseline glass and glazes. The uranium within these items is radioactive and should be treated with care.
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