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| A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | R | S | T | U | V | X | Z | ||
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| Gold | Or | Zlato | Oro | Gold | ||||||||||||||||||||
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Au Aurum |
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- Gold has been known since ancient times. The origin of the name comes from the Latin word aurum meaning gold. It is soft, malleable, bright yellow metal. Unaffected by air, water, alkalis and most acids.
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TRANSITION ELEMENT: COPPER GROUP | |
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| Relative atomic mass: | 196.96655(2) | Electronic configuration: | [Xe] 4f142 5d10 6s1 |
| Formal oxidation number: | +1 +3 | Electronegativities: | 2.4 |
| Thermal conductivity: | 317 W m-1 K-1 | Electrical resistivity (20 °C): | 2.35 μΩcm |
| Atomic radius: | 144.2 pm | Standard state (20 °C): | solid |
| Density (g dm-3): | 19320 (293 K) 17280 (m.p.) |
Molar volume (cm3 mol-1): | 10.19 (293 K) 11.11 (m.p.) |
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THERMAL PROPERTIES | |
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| Melting point: | 1064.18 °C | Heat of fusion: | 12.7 kJ mol-1 |
| Boiling point: | 2856 °C | Heat of vaporization: | 343.1 kJ mol-1 |
| Critical temperature: | 9227 °C | Heat of atomization: | 365.93 kJ mol-1 |
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IONIZATION ENERGIES AND ABUNDANCE | |
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| 1st ionization energy: | 890.13 kJ mol-1 | Abundance of element (air): | - ppm |
| 2nd ionization energy: | 1977.96 kJ mol-1 | Abundance of element (Earth's crust): | 0.003 ppm |
| 3rd ionization energy: | - kJ mol-1 | Abundance of element (oceans): | 0.000004 ppm |
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ISOTOPES | |
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Isotopes | Relative atomic mass | Abundance (%) |
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197Au | 196.966552(3) | 100 |
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MINERALS AND USES | |
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- Gold is found in veins in the crust, with copper ore and native. Used in electronics,jewellery and coins. It is a good reflector of infrared radiation, so a thin film of gold is applied to the glass of skyscrapers to reduce internal heating from sunlight. The price of 99.99 % pure gold grain is 1652.50 € for 25 g.
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REDUCTION POTENTIALS | |
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Balanced half-reaction | Eo / V | Annotation |
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Au3+ + 2e-  Au+ |
+1.41 | |
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Au3+ + 3e- Au(s) |
+1.50 | |
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Au+ + e- Au(s) |
+1.68 | |
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AuCl4- + 2e- AuCl2- + 2Cl- |
+0.926 | |
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AuBr4- + 2e- AuBr2- + 2Br- |
+0.805 | |
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AuCl4- + 3e- Au(s) + 4Cl- |
+1.002 | |
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AuBr4- + 3e- Au(s) + 4Br- |
+0.858 | |
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AuCl2- + e- Au(s) + 2Cl- |
+1.154 | |
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AuBr2- + e- Au(s) + 2Br- |
+0.963 | |
