Molybdenum: the essentials
Molybdenum is a silvery-white, hard, transition metal. Scheele discovered it in 1778. It was often confused with graphite and lead ore. Molybdenum is used in alloys, electrodes and catalysts. The World War 2 German artillery piece called "Big Bertha" contains molybdenum as an essential component of its steel.
Molybdenum: historical information
In 1778 Carl Welhelm Scheele conducted research on an ore now known as molybdenite. He concluded that it did not contain lead as was suspected at the time and reported that the mineral contained a new element that he called molybdenum after the mineral. Molybdenum metal was prepared in an impure form in 1782 by Peter Jacob Hjelm.
Molybdenum: physical properties
Molybdenum: orbital properties
Isolation: it is not normally necessary to make samples of molybdenum metal in the laboratory since it is readily available commercially. Industrially, its extraction is sometimes linked to copper production. The normal process is for the sulphide MoS2 to be "roasted" to form the oxide MoO3. This is often used directly in the steel industry.
Pure samples of the metal are available by first dissolving the oxide in ammonium hydroxide to make ammonium molybdate, (NH4)2[MO4], and thenreduction of the molybdate with hydrogen gas to form the metal.