About

Palladium is a rare, lustrous silvery-white metal in the platinum group. Like rhodium, it is a vital catalyst in catalytic converters for cars. It has the unusual ability to absorb up to 900 times its own volume of hydrogen gas, a property used for hydrogen purification and studied for hydrogen storage. It is also used in jewelry, dentistry, and electronics.

Atomic Properties

Atomic Number46

Atomic Weight106.42 u

Neutrons (common)60

Electron Configuration[Kr] 4d¹⁰

Full Configuration1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰

Electrons per Shell2, 8, 18, 18

Electronegativity2.2

Electron Affinity54.24 kJ/mol

Oxidation States+4, +2, 0

Covalent Radius131 pm

Van der Waals Radius163 pm

Ionic Radius64 pm

Periodic Table Position

Group10

Period5

BlockD

Chemical SeriesTransition metals

Physical Properties

State at STPsolid

AppearanceSilvery-white lustrous metal

Crystal Structurefcc

Magnetic Orderingparamagnetic

Speed of Sound3,070 m/s

Poisson Ratio0.39

Thermal Properties

Melting Point1,828.05 K

Boiling Point3,236 K

Thermal Expansion0 1/K

Thermal Conductivity71.8 W/(m·K)

Specific Heat0.244 J/(g·K)

Molar Heat25.97 J/(mol·K)

Heat of Fusion16.74 kJ/mol

Heat of Vaporization357 kJ/mol

Abundance

In Earth's Crust0.015 ppm

In Solar System0.006 ppm

In Universe0.002 ppm

Discovery

Discovered byWilliam Hyde Wollaston

Discovery Year1,803

Occurrenceprimordial

CAS Number7440-05-3

Electron Configuration

Energy

↿⇂

Isotopes of Palladium

Symbol ▲	Mass (u) ▲	Abundance ▲	Half-life ▲	Decay Mode ▲
¹⁰²Pd	101.905610	1.02%	Stable	Stable
¹⁰⁴Pd	103.904030	11.14%	Stable	Stable
¹⁰⁵Pd	104.905080	22.33%	Stable	Stable
¹⁰⁶Pd	105.903480	27.33%	Stable	Stable
¹⁰⁷Pd	106.905133	—	6.5 My	Beta Minus Decay
¹⁰⁸Pd	107.903890	26.46%	Stable	Stable
¹¹⁰Pd	109.905150	11.72%	Stable	Stable

Interactive Visualization

Explore the 3D Bohr model of Palladium in our interactive viewer.

View 3D Model of Palladium