Name: palladium
Symbol: Pd
Atomic number: 46
Atomic weight: 106.42 (1) g
Group in periodic table: 10
Group name: Precious metal
Period in periodic table: 5
Block in periodic table: d-block
CAS registry ID: 7440-05-3
Palladium is a steel-white metal, does not tarnish in air, and is the least dense and lowest melting of the platinum group metals. When annealed, it is soft and ductile. Cold working increases its strength and hardness. It is used in some watch springs.
At room temperatures the metal has the unusual property of absorbing up to 900 times its own volume of hydrogen. Hydrogen readily diffuses through heated palladium and this provides a means of purifying the gas.