Molybdenum is a silvery-white transition metal with a melting point of 2623 degrees Celsius. It has oxidation states ranging from -4 to +6. Many compounds of Molybdenum are insoluble in water. It was discovered in 1781 by the chemist Peter Jacob Hjelm. 

One of Molybdenum's uses is in the production of Technetium 99m. Irradiated Molybdenum undergoes beta decay to form Technetium 99m. It also plays a very important role in enzymes and nitrogen fixing bacteria. It was also used in "Moly steel" which was used in WWII in British tanks, and also in construction. Molybdenum makes a great catalyst for many reactions.