Gold
Gold is gold colored. It is the most malleable and ductile metal known. There is only one stable isotope of gold, and five radioisotopes of gold, Au-195 being the most stable with a half-life of 186 days. Gold is used as a monetary standard, in jewelry, dentistry, electronics. Au-198 is used in treating cancer and some other medical conditions. Gold has been known to exist as far back as 2600 BC. Gold comes from the Anglo-Saxon word gold. Its symbol, Au, comes from the Latin word aurum, which means gold. Gold is not particularly toxic, however it is known to cause damage to the liver and kidneys in some.
Gallery
Hi-Res Images ofChemical Elements, CC BY 3.0 <https://creativecommons.org/licenses/by/3.0>, via Wikimedia Commons, source: https://images-of-elements.com/gold.php
Physical Propertiesmass · density · phase · crystal
Atomic Mass
196.9666Da
Density
19.3000g/cm³
Phase (STP)
Solid
Melting Point
1337.3K
Boiling Point
3109.2K
Molar Heat
0.1290J/(mol·K)
Crystal Structure
FCC
Lattice Constant
4.080Å
Atomic Radiiatomic · covalent · van der Waals
Atomic (Empirical)
135.00pm
Covalent
124.00pm
Van der Waals
214.00pm
Electronic Propertieselectronegativity · ionization · affinity
Electron Configuration
[Xe] 4f14 5d10 6s
Electron Shells
2, 8, 18, 32, 18, 1
Electronegativity
2.40Pauling
Electron Affinity
2.3kJ/mol
1st Ionization Energy
9.2kJ/mol
Oxidation States
-1, +1, +2, +3, +5
Orbital DiagramAufbau · Hund's rule · Pauli exclusion
Full: 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s1Short: [Xe] 4f14 5d10 6s
Ionization Energies (79 known)
Emission Spectrumvisible range · characteristic spectral lines
Abundanceby mass
Log scale · ppm = parts per million by mass
Biological Role
No known biological role. Biologically inert. Gold compounds used to treat rheumatoid arthritis.
Discovery
Discovered By
Known to the ancients.
Named By
—
Year
—
Nuclear Data
Known Isotopes
43
Stable Isotopes
2
Stable Mass Numbers
168, 197
Natural isotopic abundance (IUPAC recommended values)
Isotopes of Au43 known
| Nuclide | Z | N | Mass (AMU) | Half-life | Decay | Jπ | Abundance |
|---|---|---|---|---|---|---|---|
| 168Austable | 79 | 89 | 168.002716 | Stable | p | — | — |
| 169Au | 79 | 90 | 168.998080 | Unknown | p, α, β⁺ | 1/2+ | — |
| 170Au | 79 | 91 | 169.996024 | 290 μs | p (0.89%), α (0.11%) | 2 | — |
| 197Austable | 79 | 118 | 196.966570 | Stable | stable (1%) | 3/2+ | 10000.0000% |
| 208Au | 79 | 129 | 207.993655 | Unknown | β⁻, β⁻n | 6+ | — |
| 209Au | 79 | 130 | 208.997606 | Unknown | β⁻, β⁻n | 3/2+ | — |
| 210Au | 79 | 131 | 210.002877 | Unknown | β⁻, β⁻n | 6+ | — |