Chromium
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Chromium (Cr) is a silver metal that has the atomic number 24 in the periodic table. It is a Transition metal and located in Group 6 of the periodic table. It has the symbol Cr.
Chromium was discovered in 1780 by the French chemist Nicolas Louis Vauquelin. It was through his work with the mineral Crocoite that he discovered when it was heated with Potassium carbonate it produced a yellow salt. In 1781 he managed to isolate the metal by heating the oxide sample with charcoal. Chromium draws its name from the Greek ‘Chroma’ meaning colour due to its ability to form multiple coloured compounds. Chromium is used extensively in the production of stainless steel and other alloys due to its high shine finish and its ability to resist corrosion. It does this as a small layer of Chromium oxide forms on the surface preventing further reaction to oxygen. Its salts are used as a variety of pigments due to the wide range of colours formed. It is located in Group 6 and it has a melting point of 1907°c and a boiling point of 2671°c being a solid metal at room temperature.
FAQ's
Louis Vauquelin
1797
Uses
Used to make stainless steel. It gives the color to rubies and emeralds. Iron-nickel-chromium alloys in various percentages yield an incredible variety of the most important metals in modern technology.
Sources
Chromite [Fe,Mg(CrO4)] is its most important mineral. Produced commercially by heating its ore in the presence of silicon or aluminium.
About the author
Nathan M
Nathan has a degree in BSc Biomedical Chemistry at Warwick University and a degree in PGCE Science at Wolverhampton University, UK. Nathan's subject matter ranges from general chemistry and organic chemistry. Nathan also created the curriculum on Breaking Atom in the course page.
Citation
Cr
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