Lead (Pb)

Lead is a post-transition metal with atomic number 82, in period 6 and group 14 of the periodic table. Its atomic mass is 207.2 u and its electron configuration is [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p². Solid at 25 °C.

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Key facts

Atomic number	82
Atomic mass	207.2 u
Category	Post-Transition Metal
Period	6
Group	14
Block	p
Electron configuration	[Xe] 4f¹⁴ 5d¹⁰ 6s² 6p²
Electrons per shell	2, 8, 18, 32, 18, 4
Electronegativity (Pauling)	2.33
Oxidation states	−4, −2, −1, +1, +2, +3, +4common in bold
State at 25 °C	Solid
Melting point	600.61 K327.46 °C
Boiling point	2022 K1748.85 °C
Density	11.34 g/cm³

Atomic properties

First ionization energy	7.417 eV
Electron affinity	35.1 kJ/mol
Atomic radius	175 pm
Covalent radius	146 pm
Van der Waals radius	202 pm
Common ions	Pb²⁺, Pb⁴⁺
Protons, neutrons, electrons	82, 125, 82

Physical and thermal properties

Molar volume	18.26 cm³/mol
Heat of fusion	4.77 kJ/mol
Heat of vaporization	178 kJ/mol
Specific heat	127 J/(kg·K)
Thermal conductivity	35 W/(m·K)
Thermal expansion	2.89 × 10⁻⁵ K⁻¹
Mohs hardness	1.5
Young’s modulus	16 GPa
Crystal structure	Face-centered cubic
Magnetic type	Diamagnetic

Identification and history

CAS number	7439-92-1
Latin name	Plumbum
Discovered by	Known since antiquity
Named by	---

Natural isotopes

Isotope	Mass (u)	Abundance
²⁰⁴Pb	203.973044	1.4 %
²⁰⁶Pb	205.974465	24.1 %
²⁰⁷Pb	206.975897	22.1 %
²⁰⁸Pb	207.976652	52.4 %

Data checked against PubChem (NIH), IUPAC, the NIST Atomic Spectra Database and the IAEA (NUBASE and AME), the same data you see in the app.

A dash (---) means there is no reliable published measurement. The app never makes one up.

See Lead in the app

Orbital diagram with Hund’s rule, emission spectrum, shell model, every isotope, a real photo, and comparison with any other element. Free, no ads, works offline.

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