• Binary compounds with halogens (known as halides), oxygen (known as oxides), hydrogen (known as hydrides), and other compounds of chromium where known. (webelements.com)
  • Chromium(VI) is a strong oxidising agent in contrast to the molybdenum(VI) and tungsten(VI) oxides. (wikipedia.org)
  • Similarly, traces of chromium incorporated into the crystal lattice of corundum (crystalline aluminium oxide, Al 2 O 3 ) as a replacement for some of the Al 3+ ions results in another highly coloured gem stone, in this case the red ruby. (webelements.com)
  • Chromium is the fourth transition metal found on the periodic table, and has an electron configuration of [Ar] 3d5 4s1. (wikipedia.org)
  • Emerald is a form of beryl (a beryllium aluminium silicate) which is green because of the inclusion of a little chromium into the beryl crytal lattice in place of some of the aluminium ions. (webelements.com)
  • While chromium metal and Cr(III) ions are considered non-toxic, hexavalent chromium, Cr(VI), is toxic and carcinogenic. (wikipedia.org)
  • The oxide is then further reduced with aluminium or silicon to form chromium metal. (webelements.com)
  • Pure chromium metal is produced by a different process: roasting and leaching of chromite to separate it from iron, followed by reduction with carbon and then aluminium. (wikipedia.org)
  • Chromium is highly resistant to tarnishing, which makes it useful as a metal that preserves its outermost layer from corroding, unlike other metals such as copper, magnesium, and aluminium. (wikipedia.org)
  • they thus contribute less to metallic bonding, and hence the melting and boiling points and the enthalpy of atomisation of chromium are lower than those of the preceding element vanadium. (wikipedia.org)
  • Chromium has a melting point of 1907 °C (3465 °F), which is relatively low compared to the majority of transition metals. (wikipedia.org)
  • A major development in steel production was the discovery that steel could be made highly resistant to corrosion and discoloration by adding metallic chromium to form stainless steel. (wikipedia.org)
  • Chromium is also greatly valued as a metal that is able to be highly polished while resisting tarnishing. (wikipedia.org)
  • Chromium is an essential trace element and has a role in glucose metabolism. (webelements.com)
  • In the United States, trivalent chromium (Cr(III)) ion is considered an essential nutrient in humans for insulin, sugar, and lipid metabolism. (wikipedia.org)
  • However, in 2014, the European Food Safety Authority, acting for the European Union, concluded that there was insufficient evidence for chromium to be recognized as essential. (wikipedia.org)
  • Chromium is extremely hard, and is the third hardest element behind carbon (diamond) and boron. (wikipedia.org)
  • Cr-50 is used for the production of the radioisotope Cr-51 which is used for measuring blood volume and red blood cell survival. (webelements.com)
  • Industrial production of chromium proceeds from chromite ore (mostly FeCr2O4) to produce ferrochromium, an iron-chromium alloy, by means of aluminothermic or silicothermic reactions. (wikipedia.org)
  • Abandoned chromium production sites often require environmental cleanup. (wikipedia.org)
  • Industrial production of chromium proceeds from chromite ore (mostly FeCr2O4) to produce ferrochromium, an iron-chromium alloy, by means of aluminothermic or silicothermic reactions. (wikipedia.org)
  • Occurrence chromium is obtained from the chromite (FeCr2O4). (cranberrycottage.net)
  • In 2000 there were approximately fifteen million tons of chromite, of which most is used for alloys (about 70 ), eg for ferrochrome (an alloy of chromium and iron with some carbon). (cranberrycottage.net)
  • Pure chromium metal is produced by a different process: roasting and leaching of chromite to separate it from iron, followed by reduction with carbon and then aluminium. (wikipedia.org)
  • Chromium is extremely hard, and is the third hardest element behind carbon (diamond) and boron. (wikipedia.org)
  • Chromium is obtained commercially by heating the chromite in the presence of aluminum or silicon (through a process of reduction). (cranberrycottage.net)
  • Chromium metal is valued for its high corrosion resistance and hardness. (wikipedia.org)
  • Chromium is also greatly valued as a metal that is able to be highly polished while resisting tarnishing. (wikipedia.org)
  • While chromium metal and Cr(III) ions are considered non-toxic, hexavalent chromium, Cr(VI), is toxic and carcinogenic. (wikipedia.org)
  • Chromium is the fourth transition metal found on the periodic table, and has an electron configuration of [Ar] 3d5 4s1. (wikipedia.org)
  • Chromium is highly resistant to tarnishing, which makes it useful as a metal that preserves its outermost layer from corroding, unlike other metals such as copper, magnesium, and aluminium. (wikipedia.org)
  • Another part (about 15 ) is directly used as refractory material, the rest in the chemical industry for various chromium compounds.Deposits have been discovered chromium metal, though scanty, in a Russian mine (Udachnaya) occur in the metal samples, where the reducing environment has facilitated the production of elemental chromium and diamond. (cranberrycottage.net)
  • Chromium is a chemical element with the symbol Cr and atomic number 24. (wikipedia.org)
  • The name of the element is derived from the Greek word χρῶμα, chrōma, meaning color, because many chromium compounds are intensely colored. (wikipedia.org)
  • they thus contribute less to metallic bonding, and hence the melting and boiling points and the enthalpy of atomisation of chromium are lower than those of the preceding element vanadium. (wikipedia.org)