Follow the palladium 12 for more information. Jump to navigation Jump to search This article is about the chemical element.
Palladium is a chemical element with symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by William Hyde Wollaston. Ore deposits of palladium and other PGMs are rare. Palladium is a soft silver-white metal that resembles platinum. It is the least dense and has the lowest melting point of the platinum group metals.
It is soft and ductile when annealed and is greatly increased in strength and hardness when cold-worked. It tarnishes lightly in a moist atmosphere containing sulfur. Naturally occurring palladium is composed of seven isotopes, six of which are stable. The most stable radioisotopes are 107Pd with a half-life of 6. For isotopes with atomic mass unit values less than that of the most abundant stable isotope, 106Pd, the primary decay mode is electron capture with the primary decay product being rhodium. Radiogenic 107Ag is a decay product of 107Pd and was first discovered in 1978 in the Santa Clara meteorite of 1976.