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Appearance | Metallic yellow |
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| 196.966570(4)[1] |
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Atomic number (Z) | 79 |
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Group | group 11 |
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Period | period 6 |
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Block | d-block |
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Electron configuration | [Xe] 4f14 5d10 6s1 |
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Electrons per shell | 2, 8, 18, 32, 18, 1 |
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Phase at STP | solid |
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Melting point | 1337.33 K (1064.18 °C, 1947.52 °F) |
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Boiling point | 3243 K (2970 °C, 5378 °F) |
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Density (near r.t.) | 19.3 g/cm3 |
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when liquid (at m.p.) | 17.31 g/cm3 |
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Heat of fusion | 12.55 kJ/mol |
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Heat of vaporization | 342 kJ/mol |
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Molar heat capacity | 25.418 J/(mol·K) |
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Vapor pressure
P (Pa) |
1 |
10 |
100 |
1 k |
10 k |
100 k |
at T (K) |
1646 |
1814 |
2021 |
2281 |
2620 |
3078 |
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Oxidation states | −3, −2, −1, 0,[2] +1, +2, +3, +5 (an amphoteric oxide) |
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Electronegativity | Pauling scale: 2.54 |
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Ionization energies | - 1st: 890.1 kJ/mol
- 2nd: 1980 kJ/mol
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Atomic radius | empirical: 144 pm |
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Covalent radius | 136±6 pm |
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Van der Waals radius | 166 pm |
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Spectral lines of gold |
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Natural occurrence | primordial |
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Crystal structure | face-centered cubic (fcc) |
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Speed of sound thin rod | 2030 m/s (at r.t.) |
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Thermal expansion | 14.2 µm/(m⋅K) (at 25 °C) |
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Thermal conductivity | 318 W/(m⋅K) |
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Electrical resistivity | 22.14 nΩ⋅m (at 20 °C) |
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Magnetic ordering | diamagnetic[3] |
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Molar magnetic susceptibility | −28.0×10−6 cm3/mol (at 296 K)[4] |
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Tensile strength | 120 MPa |
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Young's modulus | 79 GPa |
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Shear modulus | 27 GPa |
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Bulk modulus | 180 GPa[5] |
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Poisson ratio | 0.4 |
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Mohs hardness | 2.5 |
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Vickers hardness | 188–216 MPa |
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Brinell hardness | 188–245 MPa |
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CAS Number | 7440-57-5 |
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Naming | from Latin aurum, meaning gold |
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Discovery | In the Middle East (before 6000 BCE) |
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Symbol | "Au": from Latin aurum |
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Main isotopes[6] |
Decay |
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abundance |
half-life (t1/2) |
mode |
product |
195Au |
synth |
186.01 d |
ε |
195Pt |
196Au |
synth |
6.165 d |
β+ |
196Pt |
β− |
196Hg |
197Au |
100% |
stable |
198Au |
synth |
2.69464 d |
β− |
198Hg |
199Au |
synth |
3.139 d |
β− |
199Hg |
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Category: Gold | references |