Palladium is in Row 5, Group 10 of the periodic table. Along with ruthenium, rhodium, osmium, iridium, and platinum, it belongs to the platinum group of metals. These metals are sometimes also called the noble metals because they are not very reactive. Palladium has an atomic number of 46, an atomic mass of 106.42, and a chemical symbol of Pd.

Properties

Palladium is a relatively soft, silver-white metal that is both malleable and ductile. It has a melting point of 2,829°F (1,554°C), a boiling point of 5,100°F (2,800°C), and a density of 12.0 grams per cubic centimeter. A physical property of particular interest is palladium's ability to absorb hydrogen gas, somewhat like a sponge absorbs water. When a surface is coated with finely divided palladium metal, hydrogen gas passes into the space between palladium atoms, allowing the metal to absorb up to 900 times its own weight in hydrogen gas...