Cambridge Encyclopedia :: Cambridge Encyclopedia Vol. 45

lead

Pb (from Lat plumbum) element 82, a soft, dense (11·5 g/cm3) metal, melting point 328°C. Its main natural source is the sulphide (PbS). Its good corrosion resistance and easy workability led to its early use in plumbing and for containers for corrosive liquids. These uses had considerable toxic effects, as lead is slowly oxidized in the presence of air and water. It is used in quantity for the production of accumulators (storage batteries).

For "PB" or "pb" as an abbreviation, see PB.
82 thallium ← lead → bismuth
Sn

Pb

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Periodic Table - Extended Periodic Table
General
Name, Symbol, Number lead, Pb, 82
Chemical series poor metals
Group, Period, Block 14, 6, p
Appearance bluish white
Atomic mass 207.2(1) g/mol
Electron configuration [Xe] 4f 6s
Electrons per shell 2, 8, 18, 32, 18, 4
Physical properties
Phase solid
Density (near r.t.) 11.34 g·cm−3
Liquid density at m.p. 10.66 g·cm−3
Melting point 600.61 K
(327.46 °C, 621.43 °F)
Boiling point 2022 K
(1749 °C, 3180 °F)
Heat of fusion 4.77 kJ·mol−1
Heat of vaporization 179.5 kJ·mol−1
Heat capacity (25 °C) 26.650 J·mol
Vapor pressure
P/Pa 1 10 100 1 k 10 k 100 k
at T/K 978 1088 1229 1412 1660 2027
Atomic properties
Crystal structure cubic face centered
Oxidation states 4, 2
(Amphoteric oxide)
Electronegativity 2.33 (Pauling scale)
Ionization energies
(more)
1st: 715.6 kJ·mol−1
2nd: 1450.5 kJ·mol−1
3rd: 3081.5 kJ·mol−1
Atomic radius 180 pm
Atomic radius (calc.) 154 pm
Covalent radius 147 pm
Van der Waals radius 202 pm
Miscellaneous
Magnetic ordering diamagnetic
Electrical resistivity (20 °C) 208 nΩ·m
Thermal conductivity (300 K) 35.3 W·m
Thermal expansion (25 °C) 28.9 µm·m
Speed of sound (thin rod) (r.t.) (annealed)
1190  m·s−1
Young's modulus 16 GPa
Shear modulus 5.6 GPa
Bulk modulus 46 GPa
Poisson ratio 0.44
Mohs hardness 1.5
Brinell hardness 38.3 MPa
CAS registry number 7439-92-1
Selected isotopes
Main article: Isotopes of lead
iso NA half-life DM DE (MeV) DP
204Pb 1.4% >1.4×1017 y Alpha 2.186 200Hg
205Pb syn 1.53×107 y Epsilon 0.051 205Tl
206Pb 24.1% Pb is stable with 124 neutrons
207Pb 22.1% Pb is stable with 125 neutrons
208Pb 52.4% Pb is stable with 126 neutrons
210Pb trace 22.3 y Alpha 3.792 206Hg
Beta 0.064 210Bi
References

Lead (IPA: /ˈlɛd/) is a chemical element in the periodic table that has the symbol Pb (Latin: plumbum) and atomic number 82.

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