46
Pd
Palladium
106.42
Palladium (Pd)
Transition MetalGroup 10Period 5d-block-block
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.
Latin name: Palladium
Atomic Number
46
Atomic Mass
106.42 g/mol
Phase (STP)
Solid
Electron Config.
[Kr] 4d¹⁰
General
SymbolPd
Atomic Number46
Atomic Mass106.42 g/mol
CategoryTransition Metal
Group10
Period5
Blockd-block
Electron Configuration[Kr] 4d¹⁰
Valence Electrons10
Coloursilvery-white metallic
Appearancesilvery white
CAS NumberCAS7440-05-3
Physical Properties
Phase (STP)Solid
Density12.02 g/cm³
Melting Point1554.90°C · 2830.82°F · 1828.05 K
Boiling Point2962.85°C · 5365.13°F · 3236.00 K
Atomic Properties
Atomic Radius169 pm
Electronegativity2.2 Pauling
Ionization Energy804 kJ/mol
Oxidation States+2, +4
Ion ChargePd2+/Pd4+
Thermodynamic
Molar Heat25.98 J/(mol·K)
Crystal Structure
Crystal Structureface-centered cubic
Mechanical Properties
Mohs Hardness4.75
Abundance
In Universe0.000005%
In Sun0.000003%
In Earth's Crust0.00005999999999999999%
In Meteorites0.00001%
Discovery & History
Discovery Year1803
Discovered ByWilliam Hyde Wollaston
Country of DiscoveryEngland
Isotopes of Palladium
| Isotope | Abundance | Half-life | Decay |
|---|---|---|---|
| Pd-102 | 1.02% | Stable | — |
| Pd-104 | 11.14% | Stable | — |
| Pd-105 | 22.33% | Stable | — |
| Pd-106 | 27.33% | Stable | — |
| Pd-107 | — | 6.5 × 10⁶ years | β⁻ |
| Pd-108 | 26.46% | Stable | — |
| Pd-110 | 11.72% | Stable | — |