Previous Element Vanadium. Next Element Manganese. What's in a name? From the Greek word for color, chroma. Say what? Chromium is pronounced as KROH-mee-em. Chromium was discovered by Louis-Nicholas Vauquelin while experimenting with a material known as Siberian red lead, also known as the mineral crocoite PbCrO 4 , in He produced chromium oxide CrO 3 by mixing crocoite with hydrochloric acid HCl.
On the other hand, the first picture in my mind for chromium after gemstones, of course is when it is in its metallic form, such as for the mirrored corrosion and wear-resistant "chrome" surfaces of ball bearings and the shiny silvery trim on car parts.
So it's shiny and colourful as well as corrosion and wear resistant. I don't think I would say chromium had limited uses, would you? That was Oxford University's Christopher Blanford with the complex and colourful chemistry of chromium. Next week, a planetary element. We're so familiar with uranium and plutonium that it's easy to miss that they are named after the seventh and ninth planets of the solar system.
At least, Pluto was the ninth planet until it was stripped of its status in Between those planets sits Neptune, and the gap between the two elements leaves a space for their relatively unsung cousin, neptunium - element number 93 in the periodic table.
In June , American physicists Edwin McMillan and Philip Abelson, working at the Berkeley Radiation Laboratory, wrote a paper describing a reaction of uranium that had been discovered when bombarding it with neutrons using a cyclotron particle accelerator. Remarkably, the openly published Berkeley paper would show the first step to overcoming one of the biggest obstacles to building an atomic bomb.
And Brian Clegg will reveal how this obstacle was overcome in next week's Chemistry in its Element. Until then, I'm Meera Senthilingam and thank you for listening. 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 Chromium. 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. Nicholas Louis Vauquelin. Origin of the name. The name is derived from the Greek 'chroma', meaning colour.
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. Pressure Pa. Listen to Chromium Podcast. Transcript : Chemistry in its element: chromium Promo You're listening to Chemistry in its element brought to you by Chemistry World , the magazine of the Royal Society of Chemistry.
End promo Meera Senthilingam This week an element that adds sparkle and value to minerals, through the colourful characteristics of its compounds. Christopher Blanford In the Western world, the colourful history of chromium begins, suitably enough, at the far end of the visible spectrum with a red-orange mineral that was named "Siberian red lead" by its discoverer, the 18th-century geologist Johann Lehmann.
Meera Senthilingam So it's shiny and colourful as well as corrosion and wear resistant. However, consuming high levels of chromium in polluted drinking water or inhaling fumes of the heated element can cause ulcers, cancer and other health problems. French chemist Louis Nicolas Vauquelin first isolated chromium from a bright red mineral called Siberian red lead, now known as lead chromate PbCrO 4 in He mixed the chromium in a variety of solutions and was intrigued by the many colors it produced, thereby naming the element after the Greek word chroma meaning "color.
Chromium is the 21st most common element found in the Earth's crust, but it is not found in its free metal form. Instead, it is principally found in chromite ore, according to Robert E. About 20, tons of chromium metal are produced each year, and there are still about a billion tons of unexploited deposits in Greenland, Canada, and the United States, according to Emsley.
Chromium metal is then obtained by heating the chromite ore in the presence of aluminum or silicon, according to the Jefferson Lab. Chromium is a transition metal in Group 6 on the Periodic Table of Elements.
In its pure form, chromium is a silvery, lustrous, hard metal that has a high polish, ideal for electroplating. The most important chromium compounds are the chromates of sodium and potassium, the dichromates, and potassium and ammonium chrome alums, according to the Los Alamos National Laboratory.
Chromium compounds are toxic and should be handled with care. Chromium compounds are all vividly colored and are used as pigments — bright green, yellow, red and orange. Rubies are red because of chromium, and glass treated with chromium has an emerald green color, according to the Royal Society of Chemistry RSC. Using a technique called electroplating, a thin layer of chromium can coat metal and plastic objects, including car parts and household appliances, to give a shiny, attractive finish.
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