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Chromium



Chromium was discovered by Louis-Nicholas Vauquelin. It is a steely-gray, lustrous, hard and brittle metal which takes a high polish, resists tarnishing, and has a high melting point. The elements name originates from the Greek word, chrōma, meaning colour, because many of its compounds are intensely coloured. Chromium metal is of a high value due to its high corrosion resistance and hardness. A major development was the discovery that steel could be made highly resistant to corrosion and discoloration when adding metallic chromium to form stainless steel. This application, along with chrome plating currently comprises 85% of the commercial use for the element, with the application for chromium compounds in the remaining 15%.



Name Chromium
Atomic Number 24
Atomic Weight 51.966
Symbol Cr
Melting Point ( °C ) 2180 K ​(1907 °C, ​3465 °F)
Boiling Point ( °C ) 2944 K ​(2671 °C, ​4840 °F)
Density (g/cm3) 7.19 g·cm−3 (at 0 °C, 101.325 kPa)
Earth crust (%) 0.014%
Discovery (Year) 1761 by Louis Nicolas Vauquelin
Group Group 6
Electron configuration [Ar] 3d5 4s1
Ionization energy (eV) 6,7665