Gold
TRANSITION METAL · GROUP 11 · PERIOD 6
79
Au
Gold
196.97
Atomic Data
| Atomic Number | 79 |
| Symbol | Au |
| Atomic Weight | 196.97 u |
| Density (STP) | 19.3 g/cm³ |
| Melting Point | 1064.18 °C (1337.33 K) |
| Boiling Point | 2855.85 °C (3129 K) |
| Electronegativity | 2.54 (Pauling) |
| Electron Config. | 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d10 6s1 |
| Oxidation States | +1, +3 |
| Phase at STP | Solid |
| Category | Transition Metal |
| Period / Group | 6 / 11 |
| CAS Number | 7440-57-5 |
Electron Configuration
{{BOHR_SVG}}
[Xe] 4f14 5d10 6s1
| Shell | n | Subshell | Electrons | Cumulative |
|---|---|---|---|---|
| K | 1 | 1s | 2 | 2 |
| L | 2 | 2s | 2 | 4 |
| L | 2 | 2p | 6 | 10 |
| M | 3 | 3s | 2 | 12 |
| M | 3 | 3p | 6 | 18 |
| M | 3 | 3d | 10 | 28 |
| N | 4 | 4s | 2 | 30 |
| N | 4 | 4p | 6 | 36 |
| N | 4 | 4d | 10 | 46 |
| N | 4 | 4f | 14 | 60 |
| O | 5 | 5s | 2 | 62 |
| O | 5 | 5p | 6 | 68 |
| O | 5 | 5d | 10 | 78 |
| P | 6 | 6s | 1 | 79 |
| Total | 79 | 79 | ||
Isotopes of Gold
Gold is monoisotopic — ¹⁹⁷Au is its only naturally occurring stable isotope, accounting for 100% of all natural Gold.
| Isotope | Symbol | Protons | Neutrons | Abundance | Stability |
|---|---|---|---|---|---|
| Gold-197 | ¹⁹⁷Au | 79 | 118 | 100 | Stable |
Abundance & Occurrence
Gold is present in Earth's crust at approximately 0.004 ppm by mass and at approximately 0.6 ppm by mass throughout the universe.
Earth's Crust (ppm by mass)
Gold
0.004 ppm
Silicon (ref.)
277,000 ppm
Oxygen (ref.)
461,000 ppm
Universe (ppm by mass)
Gold
0.6 ppm
Helium (ref.)
230,000 ppm
Hydrogen (ref.)
739,000 ppm
Discovery & History
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Safety & Handling
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Gold in the Real World
Real-World Uses
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Downloadable Resources
Free periodic table reference sheets for classrooms, study sessions, and laboratory use.