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Lead Sheets

  

82

thalliumlead bismuth

Sn

Pb

Uuq

periodic table - Extended Periodic Table

 

Lead is a chemical element in the periodic table that has the symbol Pb (L. plumbum) and atomic number 82. A soft, heavy, toxic and malleable poor metal, lead is bluish white when freshly cut but tarnishes to dull gray when exposed to air. Lead is used in building construction, lead-acid batteries, bullets and shot, and is part of solder, pewter, and fusible alloys. Lead has the highest atomic number of all stable elements - although the next element, bismuth has a half life so long it can be considered stable.

Notable characteristics

Lead has a dull luster and is a dense, ductile, very soft, highly malleable, bluish-white metal that has poor electrical conductivity. This true metal is highly resistant to corrosion. Because of this property, it is used to contain corrosive liquids (e.g. sulfuric acid). Lead can be toughened by adding a small amount of antimony or other metals to it. Lead is the only metal in which there is zero Thomson effect. Lead is also poisonous.

Applications

Former applications


Contrary to popular belief, pencil 'leads' have never been made from lead. The term comes from the roman lead stylus, penicillus. The pencil originated as a wrapped graphite writing tool, a particular type of graphite used being named plumbago (lit. acts like lead).

 

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] 4f14 5d10 6s2 6p2

Electrons per shell

2, 8, 18, 32, 18, 4

Physical properties

Phase

solid

Density (near r.t.)

11.34 gcm−3

Liquid density at m.p.

10.66 gcm−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 kJmol−1

Heat of vaporization

179.5 kJmol−1

Heat capacity

(25 C) 26.650 Jmol−1K−1

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 kJmol−1

2nd: 1450.5 kJmol−1

3rd: 3081.5 kJmol−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 nΩm

Thermal conductivity

(300 K) 35.3 Wm−1K−1

Thermal expansion

(25 C) 28.9 mm−1K−1

Speed of sound (thin rod)

(r.t.) (annealed)
1190  ms−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%

>1.41017 y

Alpha

2.186

200Hg

205Pb

syn

1.53107 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