Gold

Gold (Au)

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.
Atomic Number79
Atomic Weight196.966569
Mass Number197
Group11
Period6
Blockd
Protons79 p+
Neutrons118 n0
Electrons79 e-
Gold-crystals.jpg Animated Bohr Model of Au (Gold) Enhanced Bohr Model of Au (Gold) Bohr Model: Au (Gold) Orbital Diagram of Au (Gold)

Properties

Atomic Radius
135 pm
Molar Volume
Covalent Radius
124 pm
Metallic Radius
134 pm
Ionic Radius
137 pm
Crystal Radius
151 pm
Van der Waals Radius
214 pm
Density
19.3 g/cm³
Energy
Proton Affinity
Electron Affinity
2.30863 eV/particle
Ionization Energy
9.225553 eV/particle
Heat of Vaporization
340 kJ/mol
Heat of Fusion
12.68 kJ/mol
Heat of Formation
368.2 kJ/mol
Electrons
Electron Shells2, 8, 18, 32, 18, 1
Valence Electrons5
Electron Configuration[Xe] 4f14 5d10 6s1
Oxidation States-3, -2, -1, 0, 1, 2, 3, 5
Electronegativity
2.4
Electrophilicity
2.404200854149471 eV/particle
Phases
PhaseSolid
Gas Phase
Boiling Point
3,109.15 K
Melting Point
1,337.33 K
Critical Pressure
Critical Temperature
Triple Point
Visual
Color
Gold
Appearancemetallic yellow
Refractive Index
Thermodynamic Properties
Thermal Conductivity
Thermal Expansion
0.0000142 1/K
Molar Heat Capacity
25.418 J/(mol K)
Specific Heat Capacity
0.129 J/(g⋅K)
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
TypeConductor
Electrical Conductivity
45 MS/m
Electrical Resistivity
0.000000022 m Ω
Superconducting Point
Magnetism
Typediamagnetic
Magnetic Susceptibility (Mass)
-0.00000000178 m³/Kg
Magnetic Susceptibility (Molar)
-0.000000000351 m³/mol
Magnetic Susceptibility (Volume)
-0.0000344
Magnetic Ordering
Curie Point
Neel Point
Structure
Crystal StructureFace Centered Cubic (FCC)
Lattice Constant
4.08 Å
Lattice Anglesπ/2, π/2, π/2
Mechanical Properties
Hardness
2.5 MPa
Bulk Modulus
220 GPa
Shear Modulus
27 GPa
Young Modulus
78 GPa
Poisson Ratio
0.44
Speed of Sound
1,740 m/s
Classification
CategoryTransition metals, Transition metals
CAS GroupIB
IUPAC GroupIB
Glawe Number66
Mendeleev Number73
Pettifor Number70
Geochemical Classnoble metal
Goldschmidt Classsiderophile
Other
Gas Basicity
Dipole Polarizability
36 ± 3 a₀
C6 Dispersion Coefficient
Allotropes
Neutron Cross Section
98.7
Neutron Mass Absorption
0.017
Quantum Numbers2S1/2
Space Group225 (Fm_3m)

Isotopes of Gold

Stable Isotopes1
Unstable Isotopes42
Radioactive Isotopes41

168Au

Abundance
Relative Atomic Mass
168.002716 ± 0.000429 Da
Mass Number168
G-Factor
Half Life
Spin
Quadrupole Moment
Discovery Year
Parity

168Au Decay Modes
Decay ModeIntensity
p (proton emission)%

169Au

AbundanceRadioactive ☢️
Relative Atomic Mass
168.99808 ± 0.00032 Da
Mass Number169
G-Factor
Half Life
Spin1/2
Quadrupole Moment
0
Discovery Year
Parity+

169Au Decay Modes
Decay ModeIntensity
p (proton emission)%
α (α emission)%
β+ (β+ decay; β+ = ϵ + e+)%

170Au

AbundanceRadioactive ☢️
Relative Atomic Mass
169.996024 ± 0.000216 Da
Mass Number170
G-Factor
Half Life
290 ± 50 us
Spin2
Quadrupole Moment
Discovery Year2002
Parity

170Au Decay Modes
Decay ModeIntensity
p (proton emission)89%
α (α emission)11%

171Au

AbundanceRadioactive ☢️
Relative Atomic Mass
170.991881533 ± 0.000022236 Da
Mass Number171
G-Factor
Half Life
22.3 ± 2.4 us
Spin1/2
Quadrupole Moment
0
Discovery Year1997
Parity+

171Au Decay Modes
Decay ModeIntensity
p (proton emission)100%
α (α emission)%

172Au

AbundanceRadioactive ☢️
Relative Atomic Mass
171.989996704 ± 0.000060287 Da
Mass Number172
G-Factor
Half Life
28 ± 4 ms
Spin2
Quadrupole Moment
Discovery Year1993
Parity

172Au Decay Modes
Decay ModeIntensity
α (α emission)100%
p (proton emission)%
β+ (β+ decay; β+ = ϵ + e+)%

173Au

AbundanceRadioactive ☢️
Relative Atomic Mass
172.986224263 ± 0.000024458 Da
Mass Number173
G-Factor
Half Life
25.5 ± 0.8 ms
Spin1/2
Quadrupole Moment
0
Discovery Year1983
Parity+

173Au Decay Modes
Decay ModeIntensity
α (α emission)86%
β+ (β+ decay; β+ = ϵ + e+)%

174Au

AbundanceRadioactive ☢️
Relative Atomic Mass
173.984908 ± 0.000109 Da
Mass Number174
G-Factor
Half Life
139 ± 3 ms
Spin3
Quadrupole Moment
Discovery Year1983
Parity-

174Au Decay Modes
Decay ModeIntensity
α (α emission)90%
β+ (β+ decay; β+ = ϵ + e+)%

175Au

AbundanceRadioactive ☢️
Relative Atomic Mass
174.981316375 ± 0.000041399 Da
Mass Number175
G-Factor
Half Life
200 ± 3 ms
Spin1/2
Quadrupole Moment
0
Discovery Year1975
Parity+

175Au Decay Modes
Decay ModeIntensity
α (α emission)88%
β+ (β+ decay; β+ = ϵ + e+)%

176Au

AbundanceRadioactive ☢️
Relative Atomic Mass
175.980116925 ± 0.000035625 Da
Mass Number176
G-Factor
Half Life
1.05 ± 0.01 s
Spin3
Quadrupole Moment
Discovery Year1975
Parity-

176Au Decay Modes
Decay ModeIntensity
α (α emission)75%
β+ (β+ decay; β+ = ϵ + e+)%

177Au

AbundanceRadioactive ☢️
Relative Atomic Mass
176.976869701 ± 0.0000107 Da
Mass Number177
G-Factor
2.3 ± 0.1
Half Life
1.501 ± 0.02 s
Spin1/2
Quadrupole Moment
0
Discovery Year1968
Parity+

177Au Decay Modes
Decay ModeIntensity
α (α emission)40%
β+ (β+ decay; β+ = ϵ + e+)60%

178Au

AbundanceRadioactive ☢️
Relative Atomic Mass
177.976056714 ± 0.000011 Da
Mass Number178
G-Factor
Half Life
3.4 ± 0.5 s
Spin2
Quadrupole Moment
Discovery Year1968
Parity+

178Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)84%
α (α emission)16%

179Au

AbundanceRadioactive ☢️
Relative Atomic Mass
178.973173666 ± 0.000012555 Da
Mass Number179
G-Factor
2.02 ± 0.1
Half Life
7.1 ± 0.3 s
Spin1/2
Quadrupole Moment
0
Discovery Year1968
Parity+

179Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)78%
α (α emission)22%

180Au

AbundanceRadioactive ☢️
Relative Atomic Mass
179.972489738 ± 0.000005108 Da
Mass Number180
G-Factor
Half Life
7.9 ± 0.3 s
Spin1
Quadrupole Moment
Discovery Year1977
Parity+

180Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)99.42%
α (α emission)0.58%

181Au

AbundanceRadioactive ☢️
Relative Atomic Mass
180.970079102 ± 0.000021445 Da
Mass Number181
G-Factor
Half Life
13.7 ± 1.4 s
Spin5/2
Quadrupole Moment
Discovery Year1968
Parity-

181Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)97.3%
α (α emission)2.7%

182Au

AbundanceRadioactive ☢️
Relative Atomic Mass
181.969614433 ± 0.000020143 Da
Mass Number182
G-Factor
0.65 ± 0.05
Half Life
15.5 ± 0.4 s
Spin2
Quadrupole Moment
Discovery Year1970
Parity+

182Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
α (α emission)0.13%

183Au

AbundanceRadioactive ☢️
Relative Atomic Mass
182.967588106 ± 0.000010116 Da
Mass Number183
G-Factor
0.784 ± 0.008
Half Life
42.8 ± 1 s
Spin5/2
Quadrupole Moment
Discovery Year1968
Parity-

183Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)99.45%
α (α emission)0.55%

184Au

AbundanceRadioactive ☢️
Relative Atomic Mass
183.967451523 ± 0.000023912 Da
Mass Number184
G-Factor
0.412 ± 0.004
Half Life
20.6 ± 0.9 s
Spin5
Quadrupole Moment
4.7 ± 0.3
Discovery Year1969
Parity+

184Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
α (α emission)0.013%

185Au

AbundanceRadioactive ☢️
Relative Atomic Mass
184.965798871 ± 0.0000028 Da
Mass Number185
G-Factor
0.864 ± 0.008
Half Life
4.25 ± 0.06 m
Spin5/2
Quadrupole Moment
-1.1 ± 0.1
Discovery Year1960
Parity-

185Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)99.74%
α (α emission)0.26%

186Au

AbundanceRadioactive ☢️
Relative Atomic Mass
185.965952703 ± 0.000022509 Da
Mass Number186
G-Factor
-0.42 ± 0.01
Half Life
10.7 ± 0.5 m
Spin3
Quadrupole Moment
3.1 ± 0.06
Discovery Year1960
Parity-

186Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
α (α emission)0.0008%

187Au

AbundanceRadioactive ☢️
Relative Atomic Mass
186.964542147 ± 0.000024153 Da
Mass Number187
G-Factor
1.066 ± 0.03
Half Life
8.3 ± 0.2 m
Spin1/2
Quadrupole Moment
0
Discovery Year1955
Parity+

187Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
α (α emission)%

188Au

AbundanceRadioactive ☢️
Relative Atomic Mass
187.965247966 ± 0.0000029 Da
Mass Number188
G-Factor
-0.07 ± 0.03
Half Life
8.84 ± 0.06 m
Spin1
Quadrupole Moment
Discovery Year1955
Parity-

188Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

189Au

AbundanceRadioactive ☢️
Relative Atomic Mass
188.963948286 ± 0.000021558 Da
Mass Number189
G-Factor
0.984 ± 0.028
Half Life
28.7 ± 0.4 m
Spin1/2
Quadrupole Moment
0
Discovery Year1955
Parity+

189Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
α (α emission)3%

190Au

AbundanceRadioactive ☢️
Relative Atomic Mass
189.964751746 ± 0.0000037 Da
Mass Number190
G-Factor
-0.065 ± 0.007
Half Life
42.8 ± 1 m
Spin1
Quadrupole Moment
Discovery Year1959
Parity-

190Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
α (α emission)1%

191Au

AbundanceRadioactive ☢️
Relative Atomic Mass
190.963716452 ± 0.000005288 Da
Mass Number191
G-Factor
0.090933333333333 ± 0.0006
Half Life
3.18 ± 0.08 h
Spin3/2
Quadrupole Moment
0.72 ± 0.02
Discovery Year1954
Parity+

191Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

192Au

AbundanceRadioactive ☢️
Relative Atomic Mass
191.964817615 ± 0.000016991 Da
Mass Number192
G-Factor
-0.0107 ± 0.0015
Half Life
4.94 ± 0.09 h
Spin1
Quadrupole Moment
-0.228 ± 0.008
Discovery Year1948
Parity-

192Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

193Au

AbundanceRadioactive ☢️
Relative Atomic Mass
192.964138442 ± 0.000009311 Da
Mass Number193
G-Factor
0.092733333333333 ± 0.00033333333333333
Half Life
17.65 ± 0.15 h
Spin3/2
Quadrupole Moment
0.66 ± 0.02
Discovery Year1948
Parity+

193Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%
α (α emission)%

194Au

AbundanceRadioactive ☢️
Relative Atomic Mass
193.965419051 ± 0.000002273 Da
Mass Number194
G-Factor
0.076 ± 0.0013
Half Life
38.02 ± 0.1 h
Spin1
Quadrupole Moment
-0.24 ± 0.009
Discovery Year1948
Parity-

194Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)100%

195Au

AbundanceRadioactive ☢️
Relative Atomic Mass
194.965037823 ± 0.000001201 Da
Mass Number195
G-Factor
0.098733333333333 ± 0.0004
Half Life
186.01 ± 0.06 d
Spin3/2
Quadrupole Moment
0.607 ± 0.018
Discovery Year1948
Parity+

195Au Decay Modes
Decay ModeIntensity
ϵ (electron capture)100%

196Au

AbundanceRadioactive ☢️
Relative Atomic Mass
195.966571213 ± 0.000003179 Da
Mass Number196
G-Factor
0.29415 ± 0.00025
Half Life
6.165 ± 0.011 d
Spin2
Quadrupole Moment
0.81 ± 0.07
Discovery Year1937
Parity-

196Au Decay Modes
Decay ModeIntensity
β+ (β+ decay; β+ = ϵ + e+)93%
β (β decay)7%

197Au

Abundance
100
Relative Atomic Mass
196.966570103 ± 0.000000581 Da
Mass Number197
G-Factor
0.0968 ± 0.00013333333333333
Half Life
Spin3/2
Quadrupole Moment
0.547 ± 0.016
Discovery Year1935
Parity+

198Au

AbundanceRadioactive ☢️
Relative Atomic Mass
197.968243714 ± 0.000000579 Da
Mass Number198
G-Factor
0.29555 ± 0.0004
Half Life
2.69464 ± 0.00014 d
Spin2
Quadrupole Moment
0.64 ± 0.019
Discovery Year1937
Parity-

198Au Decay Modes
Decay ModeIntensity
β (β decay)100%

199Au

AbundanceRadioactive ☢️
Relative Atomic Mass
198.968766573 ± 0.000000581 Da
Mass Number199
G-Factor
0.18033333333333 ± 0.00053333333333333
Half Life
3.139 ± 0.007 d
Spin3/2
Quadrupole Moment
0.51 ± 0.016
Discovery Year1937
Parity+

199Au Decay Modes
Decay ModeIntensity
β (β decay)100%

200Au

AbundanceRadioactive ☢️
Relative Atomic Mass
199.970756558 ± 0.000028681 Da
Mass Number200
G-Factor
Half Life
48.4 ± 0.3 m
Spin1
Quadrupole Moment
Discovery Year1951
Parity-

200Au Decay Modes
Decay ModeIntensity
β (β decay)100%

201Au

AbundanceRadioactive ☢️
Relative Atomic Mass
200.971657678 ± 0.000003455 Da
Mass Number201
G-Factor
Half Life
26 ± 0.8 m
Spin3/2
Quadrupole Moment
Discovery Year1952
Parity+

201Au Decay Modes
Decay ModeIntensity
β (β decay)100%

202Au

AbundanceRadioactive ☢️
Relative Atomic Mass
201.973856 ± 0.000025 Da
Mass Number202
G-Factor
Half Life
28.4 ± 1.2 s
Spin1
Quadrupole Moment
Discovery Year1967
Parity-

202Au Decay Modes
Decay ModeIntensity
β (β decay)100%

203Au

AbundanceRadioactive ☢️
Relative Atomic Mass
202.975154492 ± 0.000003309 Da
Mass Number203
G-Factor
Half Life
60 ± 6 s
Spin3/2
Quadrupole Moment
Discovery Year1952
Parity+

203Au Decay Modes
Decay ModeIntensity
β (β decay)100%

204Au

AbundanceRadioactive ☢️
Relative Atomic Mass
203.97811 ± 0.000215 Da
Mass Number204
G-Factor
Half Life
38.3 ± 1.3 s
Spin2
Quadrupole Moment
Discovery Year1972
Parity-

204Au Decay Modes
Decay ModeIntensity
β (β decay)100%

205Au

AbundanceRadioactive ☢️
Relative Atomic Mass
204.980064 ± 0.000215 Da
Mass Number205
G-Factor
Half Life
32 ± 1.4 s
Spin3/2
Quadrupole Moment
Discovery Year1994
Parity+

205Au Decay Modes
Decay ModeIntensity
β (β decay)100%

206Au

AbundanceRadioactive ☢️
Relative Atomic Mass
205.984766 ± 0.000322 Da
Mass Number206
G-Factor
Half Life
47 ± 11 s
Spin6
Quadrupole Moment
Discovery Year2009
Parity+

206Au Decay Modes
Decay ModeIntensity
β (β decay)100%

207Au

AbundanceRadioactive ☢️
Relative Atomic Mass
206.988577 ± 0.000322 Da
Mass Number207
G-Factor
Half Life
Spin3/2
Quadrupole Moment
Discovery Year2010
Parity+

207Au Decay Modes
Decay ModeIntensity
β (β decay)%
β n (β-delayed neutron emission)%

208Au

AbundanceRadioactive ☢️
Relative Atomic Mass
207.993655 ± 0.000322 Da
Mass Number208
G-Factor
Half Life
Spin6
Quadrupole Moment
Discovery Year2010
Parity+

208Au Decay Modes
Decay ModeIntensity
β (β decay)%
β n (β-delayed neutron emission)%

209Au

AbundanceRadioactive ☢️
Relative Atomic Mass
208.997606 ± 0.000429 Da
Mass Number209
G-Factor
Half Life
Spin3/2
Quadrupole Moment
Discovery Year2010
Parity+

209Au Decay Modes
Decay ModeIntensity
β (β decay)%
β n (β-delayed neutron emission)%

210Au

AbundanceRadioactive ☢️
Relative Atomic Mass
210.002877 ± 0.000429 Da
Mass Number210
G-Factor
Half Life
Spin6
Quadrupole Moment
Discovery Year2010
Parity+

210Au Decay Modes
Decay ModeIntensity
β (β decay)%
β n (β-delayed neutron emission)%

History

Gold has been known since prehistoric times and was the first metal used by humans. Gold artifacts dated to 5000 years ago have been found in Egyptian tombs. Gold of 98% purity has been found in Nahal Qunah in the ancient kingdom of Israel, dating from about 6000 years ago. From the Latin word aurum meaning gold

DiscoverersKnown to the ancients.
Discovery Location
Discovery Year
Etymology (Name Origin)Anglo-Saxon: geolo (yellow); symbol from Latin: aurum (shining dawn).
PronunciationGOLD (English)
Gold is considered to be non-toxic
India is the world's largest single consumer of gold

Uses

Gold is used in coinage and is a standard for monetary systems in many countries. It is also extensively used for jewelry, decoration, dental work, and for plating. Gold is used widely in microelectronic circuits to ensure reliable, corrosion-resistant and static-free performance. Gold leaf, flake or dust is used in some gourmet foods as decorative ingredient. Very malleable. Used in electronics, jewelry 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.

Sources

Found in veins in the crust, with cooper ore and native .

Abundance
Abundance in Earth's crust
0.004 mg/kg
Abundance in Oceans
0.000004 mg/L
Abundance in Human Body
0.00001 %
Abundance in Meteor
0.000017 %
Abundance in Sun
0.0000001 %
Abundance in Universe
0.00000006 %

Nuclear Screening Constants

1s1.5239
2p4.4868
2s20.6302
3d13.4917
3p22.297
3s23.2372
4d37.472
4f38.3504
4p35.4532
4s34.5868
5d58.8735
5p53.83
5s51.6725
6s68.062