About

Lead is a heavy, soft, and malleable post-transition metal with a low melting point. Its high density makes it an excellent shield against radiation, particularly X-rays and gamma rays, used in hospitals and nuclear facilities. It is the primary component of lead-acid batteries used in cars. Its use in paint, gasoline, and plumbing has been phased out due to its neurotoxicity.

Atomic Properties

Atomic Number82

Atomic Weight207.2 u

Neutrons (common)126

Electron Configuration[Xe] 4f¹⁴ 5d¹⁰ 6s² 6p²

Full Configuration1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 6s² 6p²

Electrons per Shell2, 8, 18, 32, 18, 4

Electronegativity2.33

Electron Affinity34.42 kJ/mol

Oxidation States+4, +2

Covalent Radius147 pm

Van der Waals Radius202 pm

Ionic Radius119 pm

Periodic Table Position

Group14

Period6

BlockP

Chemical SeriesPost-transition metals

Physical Properties

State at STPsolid

Appearancebluish-white lustrous metal that tarnishes to a dull gray

Crystal Structurefcc

Magnetic Orderingdiamagnetic

Speed of Sound1,210 m/s

Poisson Ratio0.44

Thermal Properties

Melting Point600.61 K

Boiling Point2,022 K

Triple Point600.61 K

Thermal Expansion0 1/K

Thermal Conductivity35.3 W/(m·K)

Specific Heat0.129 J/(g·K)

Molar Heat26.65 J/(mol·K)

Heat of Fusion4.77 kJ/mol

Heat of Vaporization179.5 kJ/mol

Abundance

In Earth's Crust14 ppm

In Ocean0 ppm

In Solar System0.01 ppm

In Human Body1.7 ppm

In Universe0.2 ppm

Discovery

Discovery YearKnown since antiquity

Occurrenceprimordial

CAS Number7439-92-1

Electron Configuration

Energy

↿⇂

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Isotopes of Lead

Symbol ▲	Mass (u) ▲	Abundance ▲	Half-life ▲	Decay Mode ▲
²⁰²Pb	201.973040	—	52.5 ky	Electron Capture
²⁰³Pb	202.974220	—	51.924 h	Electron Capture
²⁰⁴Pb	203.973040	1.4%	Stable	Stable
²⁰⁵Pb	204.974480	Trace	17.0 My	Electron Capture
²⁰⁶Pb	205.974460	24.1%	Stable	Stable
²⁰⁷Pb	206.975890	22.1%	Stable	Stable
²⁰⁸Pb	207.976650	52.4%	Stable	Stable

Interactive Visualization

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

View 3D Model of Lead