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| Lead | |
|---|---|
| Pronunciation | / l ɛ d / ⓘ ( led ) |
| Alternative name | Plumbum, pronounced: / ˈ p l ʌ m . b ə m / ⓘ ( PLUM -bəhm ) |
| Appearance | metallic gray |
| Standard atomic weight A r°(Pb) | |
| [ 1 ] | [ 206.14 , 207.94 ] · 207.2 ± 1.1 ( abridged ) |
| Lead in the periodic table | |
| Hydrogen | Helium |
| Lithium | Beryllium |
| Sodium | Magnesium |
| Potassium | Calcium |
| Rubidium | Strontium |
| Caesium | Barium |
| Francium | Radium |
| Atomic number ( Z ) | 82 |
| Group | group 14 (carbon group) |
| Period | period 6 |
| Block | p-block |
| Electron configuration | [ Xe ] 4f14 5d10 6s2 6p2 |
| Electrons per shell | 2, 8, 18, 32, 18, 4 |
| Physical properties | |
| Phase at STP | solid |
| Melting point | 600.61 K (327.46 °C, 621.43 °F) |
| Boiling point | 2022 K (1749 °C, 3180 °F) |
| Density (at 20 °C) | 11.348 g/cm3 |
| when liquid (at m.p. ) | 10.66 g/cm3 |
| Heat of fusion | 4.77 kJ/mol |
| Heat of vaporization | 179.5 kJ/mol |
| Molar heat capacity | 26.650 J/(mol · K) |
| Specific heat capacity | 128.62 J/(kg · K) |
| 978 | 1088 |
| Atomic properties | |
| Oxidation states | common: +2, +4 / −4, −2, −1, 0, +1, +3 |
| Electronegativity | Pauling scale: 2.33 (in +4), 1.87 (in +2) |
| Ionization energies | 1st: 715.6 kJ/mol · 2nd: 1450.5 kJ/mol · 3rd: 3081.5 kJ/mol |
| Atomic radius | empirical: 175 pm |
| Covalent radius | 146±5 pm |
| Van der Waals radius | 202 pm |
| Other properties | |
| Natural occurrence | primordial |
| Crystal structure | face-centered cubic (fcc) ( cF4 ) |
| Thermal expansion | 28.73 × 10−6 /K (at 20 °C) |
| Thermal conductivity | 35.3 W/(m⋅K) |
| Electrical resistivity | 208 nΩ⋅m (at 20 °C) |
| Magnetic ordering | diamagnetic |
| Molar magnetic susceptibility | −23.0 × 10−6 cm3/mol (at 298 K) |
| Young's modulus | 16 GPa |
| Shear modulus | 5.6 GPa |
Wikipedia
Chemical element with atomic number 82 (Pb)
Lead is a chemical element with the symbol Pb and has the atomic number 82. It is a heavy metal, meaning it is denser than most common materials. Lead is malleable and soft, meaning it can be shaped into different shapes and lead has a relatively low melting point. When freshly cut or melted, it appears shiny silvery with a bluish tint, but tarnishes to dull gray on exposure to air. Lead has the highest atomic number of any stable element, and three of its isotopes are endpoints of major nuclear decay chains of heavier elements.