About

Platinum is a dense, malleable, and highly unreactive precious metal. It is prized in jewelry for its brilliant white luster and resistance to tarnish. Industrially, it is a vital catalyst, used extensively in automotive catalytic converters, petroleum refining, and in the production of chemicals like nitric acid. Its stability also makes it ideal for laboratory equipment and medical devices.

Atomic Properties

Atomic Number78

Atomic Weight195.084 u

Neutrons (common)117

Electron Configuration[Xe] 4f¹⁴ 5d⁹ 6s¹

Full Configuration1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d⁹ 6s¹

Electrons per Shell2, 8, 18, 32, 17, 1

Electronegativity2.28

Electron Affinity205.041 kJ/mol

Oxidation States0, +1, +2, +3, +4, +5, +6

Covalent Radius128 pm

Van der Waals Radius175 pm

Ionic Radius80 pm

Periodic Table Position

Group10

Period6

BlockD

Chemical SeriesTransition metals

Physical Properties

State at STPsolid

Appearancesilvery white, metallic

Crystal Structurefcc

Magnetic Orderingparamagnetic

Speed of Sound2,800 m/s

Poisson Ratio0.38

Thermal Properties

Melting Point2,041.4 K

Boiling Point4,098 K

Triple Point2,041.4 K

Thermal Expansion0 1/K

Thermal Conductivity71.6 W/(m·K)

Specific Heat0.133 J/(g·K)

Molar Heat25.9 J/(mol·K)

Heat of Fusion19.66 kJ/mol

Heat of Vaporization510 kJ/mol

Abundance

In Earth's Crust0.005 ppm

In Solar System0.001 ppm

In Universe0.005 ppm

Discovery

Discovered byAntonio de Ulloa

Discovery Year1,735

Occurrenceprimordial

CAS Number7440-06-4

Electron Configuration

Energy

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Isotopes of Platinum

Symbol ▲	Mass (u) ▲	Abundance ▲	Half-life ▲	Decay Mode ▲
¹⁹⁰Pt	189.959930	0.012%	483 Gy	Alpha Decay
¹⁹²Pt	191.961030	0.782%	Stable	Stable
¹⁹⁴Pt	193.962680	32.864%	Stable	Stable
¹⁹⁵Pt	194.964790	33.775%	Stable	Stable
¹⁹⁶Pt	195.964950	25.211%	Stable	Stable
¹⁹⁸Pt	197.967890	7.356%	Stable	Stable

Interactive Visualization

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

View 3D Model of Platinum