Palladium

Palladium (Pd)

Soft white ductile transition element. Found with some copper and nickel ores. Does not react with oxygen at normal temperatures. Dissolves slowly in hydrochloric acid. Discovered in 1803 by W.H. Wollaston.
Atomic Number46
Atomic Weight106.42
Mass Number106
Group10
Period5
Blockd
Protons46 p+
Neutrons60 n0
Electrons46 e-
Palladium 1-noReflection.jpg Animated Bohr Model Enhanced Bohr Model Bohr Model Orbital Diagram

Properties

Atomic Radius
140 pm
Atomic Volume
Covalent Radius
120 pm
Metallic Radius
128 pm
Ionic Radius
59 pm
Crystal Radius
73 pm
Van der Waals radius
210 pm
Density
Boiling Point
3,413 K
Melting Point
1,825 K
Electrons per shell2, 8, 18, 18
Electronegativity
2.2
Electrophilicity
1.2731693769984 eV/particle
Proton Affinity
696 kJ/mol
Electron Affinity
Ionization Potential
8.33686 eV/particle
Heat of Vaporization
372.4 kJ/mol
Heat of Fusion
17.24 kJ/mol
Heat of Formation
376.6 kJ/mol
Molar Heat Capacity
25.98 J/(mol K)
Specific Heat Capacity
0.246 J/(g⋅K)
Thermal Conductivity
71.8 W/(m K)
Gas Basicity
673.4 kJ/mol
Dipole Polarizability
26.14 a₀
C6 Dispersion Coefficient
Oxidation States2, 4
Color
Silver
Crystal StructureFace Centered Cubic (FCC)
Lattice Constant
3.89 Å
Bulk Modulus
Electrical Resistivity
Electron Configuration[Kr] 4d10
Magnetic Ordering
Magnetic Susceptibility
PhaseSolid
Poisson Ratio
Shear Modulus
Young's Modulus
Allotropes
Alternate Names
Adiabatic Index
Appearance
Electric Conductivity
Critical Pressure
Critical Temperature
Curie Point
Electrical
Hardness
Magnetic Susceptibility
Magnetic
Neel Point
Neutron Cross Section
Neutron Mass Absorption
Gas Phase
Quantum Numbers
Refractive Index
Space Group
Speed of Sound
Superconducting Point
Thermal Expansion
Valence Electrons
Classification
CategoryTransition metals, Transition metals
CAS GroupVIIIA
IUPAC GroupVIII
Glawe Number65
Mendeleev Number68
Pettifor Number69
Geochemical Classnoble metal
Goldschmidt Classsiderophile
Radioactivity
RadioactiveNo
Decay Mode
Half-Life
Lifetime
Abundance
Abundance in Earth's crust
0.015 mg/kg
Abundance in Oceans
Abundance in Human Body
Abundance in Meteor
Abundance in Sun
Abundance in Universe2×10-7%

Isotopes of Palladium

Stable Isotopes
102Pd 104Pd 105Pd 106Pd 108Pd 110Pd
Unstable Isotopes
91Pd 92Pd 93Pd 94Pd 95Pd 96Pd 97Pd 98Pd 99Pd 100Pd 101Pd 103Pd 107Pd 109Pd 111Pd 112Pd 113Pd 114Pd 115Pd 116Pd 117Pd 118Pd 119Pd 120Pd 121Pd 122Pd 123Pd 124Pd

History

Palladium was discovered in 1803, in London, by English chemist William Hyde Wollaston. He examined the residues left from platinum after dissolving it in aqua regia, a concentrated solution of hydrochloric and nitric acids. He then isolated palladium in a series of chemical reactions. Palladium was named after the asteroid Pallas; Pallas was the Greek goddess of wisdom

DiscoverersWilliam Wollaston
Discovery LocationEngland
Discovery Year1803
Name OriginNamed after the asteroid, Pallas, discovered in 1803.
Palladium is considered to be of low toxicity
In the late 1800s, palladium was more expensive than platinum

Uses

The largest use of palladium is in catalytic converters in the automobile industry. Finely divided palladium is a good catalyst and is used for hydrogenation and dehydrogenation reactions. The metal is used in dentistry, watch making, and in making surgical instruments and electrical contacts. Used as a substitue for silver in dental items and jewelry. The pure metal is used as the delicate mainsprings in analog wristwatches. Also used in surgical instruments and as catalyst .

Sources

Obtained with platinum, nickel, copper and mercury ores.