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Cobalt is a chemical element; it has symbol Co and atomic number 27. As with nickel, cobalt is found in the Earth's crust only in a chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, somewhat brittle, gray metal.
The first elemental metal with a clearly identifiable discoverer is cobalt, discovered in 1735 by Georg Brandt, by which time the Scientific Revolution was in full swing. [6] (Even then, cobalt might have been prepared before the 13th century by alchemists roasting and reducing its ore, but,in any case, its distinct nature was not recognised.) [7]
Georg Brandt (26 June 1694 – 29 April 1768) [1] [2] was a Swedish chemist and mineralogist who discovered cobalt c. 1735. He was the first person to discover a metal unknown in ancient times. [3] [4] He is also known for exposing fraudulent alchemists operating during his lifetime. [5]
The two discovered a new element in a molybdenum sample that was used in a cyclotron, the first element to be discovered by synthesis. It had been predicted by Mendeleev in 1871 as eka-manganese. [171] [172] [173] In 1952, Paul W. Merrill found its spectral lines in S-type red giants. [174]
Note: René Haüy discovered that emeralds and beryls crystals are geometrically identical. He asked Vauquelin for a chemical analysis, and so Vauquelin found a new "earth" (beryllium oxide). Carl Wilhelm Scheele (1742 –1786), discovery of oxygen with Priestley; identification of molybdenum, tungsten, barium, hydrogen, and chlorine.
In diagnostic imaging, heavy metals such as cobalt or tungsten make up the anode materials found in x-ray tubes. [247] In electron microscopy, heavy metals such as lead, gold, palladium, platinum, or uranium have been used in the past to make conductive coatings and to introduce electron density into biological specimens by staining , negative ...
The compounds cobalt silicate and cobalt(II) aluminate (CoAl 2 O 4, cobalt blue) give a distinctive deep blue color to glass, ceramics, inks, paints and varnishes. Cobalt occurs naturally as only one stable isotope, cobalt-59. Cobalt-60 is a commercially important radioisotope, used as a radioactive tracer and for the production of high-energy ...
An image from John Dalton's A New System of Chemical Philosophy, the first modern explanation of atomic theory.. This timeline of chemistry lists important works, discoveries, ideas, inventions, and experiments that significantly changed humanity's understanding of the modern science known as chemistry, defined as the scientific study of the composition of matter and of its interactions.