All practice pages/Interatomic theory/Elements
Element 42, a transition metal
A metal that keeps its strength in the heat, named after lead by mistake, and needed by the bacteria that turn air into plant food.
Period 5, group 6. The other transition metals are tinted, and every cell opens its own article.
Like other transition metals, molybdenum loses its outer s electrons, and often some d electrons as well, to form positive ions, and it can form more than one kind.
Mined mostly as molybdenite (MoS₂) in China, Chile, Peru and the United States, often as a byproduct of copper mining. The Climax mine in Colorado was once the world's largest source.
Carl Wilhelm Scheele showed in 1778 that molybdenite was neither graphite nor a lead ore, as people had assumed, and Peter Jacob Hjelm isolated the metal in 1781. The name comes from the Greek molybdos, lead, because the soft black mineral had been mistaken for lead ore.
About 80% goes into steels and alloys that must stay strong and resist corrosion when hot, for tools, armor, pipelines and engine parts. Molybdenum disulfide is a slippery lubricant, molybdenum catalysts remove sulfur from fuels, and molybdenum-99 is the source of the technetium-99m used in medical scans. Nitrogen-fixing bacteria need molybdenum in their key enzyme.