Palladium Palladium 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. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired by her when she slew Pallas. Palladium, platinum, rhodium, ruthenium, iridium and osmium form a group of elements referred to as the platinum group metals (PGMs). These have similar chemical properties, but palladium has the lowest melting point and is the least dense of them. More than half the supply of palladium
Chemistry: A Volatile History two new elements, cesium and rubidium. In 1875, the Parisian chemist Paul Emile Lecoq de Boisbaudran used a spectroscope to discover a new metallic element. It was a silvery-white, soft metal with an atomic weight of 68, which he named gallium, after his native France. It also turned out to have a very low melting point, thus matching all the expected properties of the element Mendeleev expected to fill the gap he had left after zinc; indeed, this is exactly where the element was placed in the periodic table. Even though Mendeleev had left the necessary gap for gallium as