Molybdenum was first discovered in 1778 by a Swedish chemist
named Carl William Scheele who thought that he was observing
lead while studying a sample of molybdenite. Named from
the Greek word "molybdos, which actually means lead, Scheele
notice an apparent visual similarity, which upon further
analysis, proved to be incorrect. His studies led him to
conclude that the ore sample did not contain lead, but a new
element, which he named molybdenum after the mineral molybdenite.
Though Scheele is credited with the discovery of molybdenum in
its elemental (oxide) form, it was Peter Hjelm who in 1782 first
reduced the oxide with carbon to produced the gray metallic
powder which he also named molybdenum.
After the initial isolation of molybdenum in 1782, a commercial
application for molybdenum was not identified until the early
1900's. Industrial and Military applications required stronger
steels with greater resistance to corrosion and damage. The
First World War saw the demand for molybdenum rise dramatically
as alloyed steels used for transportation and armor plating
increased with the war effort. It was found that molybdenum
could impart an impact resistance similar to tungsten when
alloyed with steel, with less weight. Demand for molybdenum
initiated an intensive search for new sources to insure a
reliable supply. This led to the discovery of the enormous
Climax deposit in Colorado, which began production in 1918. In
addition to primary molybdenum mines, molybdenum is also
recovered as a byproduct of copper and tungsten mining
operations. The metal is produced from purified ammonium
molybdate or molybdic trioxide powder through hydrogen reduction
at high temperatures.
In its elemental form, Molybdenum is a silvery-white metallic
element. Its symbol in the periodic table is Mo and its atomic
number is 42. Though molybdenum is chemically stable, it will
react with acids.