Gold Element Information, Facts, Properties, Trends, Uses, Comparison with other elements
Gold is a chemical element with symbol Au (from Latin:aurum) and atomic number 79. In its purest form, it is a bright, slightly reddish yellow, dense, soft, malleable and ductile metal. Chemically, gold is a Transition Metal and a group 11 element.
It belongs to group 11 of the periodic table having trivial name coinage metals. You can also download Printable Periodic Table of Elements Flashcards for Gold in a PDF format.
Gold Facts
Read key information and facts about element Gold
| Name | Gold |
| Atomic Number | 79 |
| Atomic Symbol | Au |
| Atomic Weight | 196.96655 |
| Phase | Solid |
| Color | Gold |
| Appearance | metallic yellow |
| Classification | Transition Metal |
| Natural Occurance | Primordial |
| Group in Periodic Table | 11 |
| Group Name | copper family |
| Period in Periodic Table | period 6 |
| Block in Periodic Table | d-block |
| Electronic Configuration | [Xe] 4f14 5d10 6s1 |
| Electronic Shell Structure (Electrons per shell) | 2, 8, 18, 32, 18, 1 |
| Melting Point | 1337.33 K |
| Boiling Point | 3129 K |
| CAS Number | CAS7440-57-5 |
How to Locate Gold on Periodic Table
Periodic table is arranged by atomic number, number of protons in the nucleus which is same as number of electrons. The atomic number increases from left to right. Periodic table starts at top left ( Atomic number 1) and ends at bottom right (atomic number 118). Therefore you can directly look for atomic number 79 to find Gold on periodic table.
Another way to read periodic table and locate an element is by using group number (column) and period number (row). To locate Gold on periodic table look for cross section of group 11 and period 6 in the modern periodic table.
Gold History
The element Gold was discovered by Bulgaria in year Before 6000 BCE . Gold was first isolated by Varna Necropolis in ca. 4400 BCE. Gold derived its name from English word (aurum in Latin).
| Discovered By | Bulgaria |
| Discovery Date | Before 6000 BCE |
| First Isolation | |
| Isolated by |
The oldest golden treasure in the world, dating from 4,600 BC to 4,200 BC, was discovered at the burial site Varna Necropolis.
Gold Uses
Gold is one of the most coveted metals in the world, because it can be easily shaped and sculpted, conducts electricity well, and does not corrode. Aside from its use in coinage and jewelry, it is used in gears for watches, artificial limb joints, and electrical connectors. Gold nanoparticles are used as industrial catalysts.
Gold Presence: Abundance in Nature and Around Us
The table below shows the abundance of Gold in Universe, Sun, Meteorites, Earth's Crust, Oceans and Human Body.
| ppb by weight (1ppb =10^-7 %) | ppb by atoms (1ppb =10^-7 %) | |
|---|---|---|
| Abundance in Universe | 0.6 | 0.004 |
| Abundance in Sun | 1 | 0.01 |
| Abundance in Meteorites | 170 | 20 |
| Abundance in Earth's Crust | 3.1 | 0.3 |
| Abundance in Oceans | 0.05 | 0.0016 |
| Abundance in Humans | 100 | 3 |
Crystal Structure of Gold
The solid state structure of Gold is Face Centered Cubic.
The Crystal structure can be described in terms of its unit Cell. The unit Cells repeats itself in three dimensional space to form the structure.
Unit Cell Parameters
The unit cell is represented in terms of its lattice parameters, which are the lengths of the cell edges Lattice Constants (a, b and c)
| a | b | c |
|---|---|---|
| 407.82 pm | 407.82 pm | 407.82 pm |
and the angles between them Lattice Angles (alpha, beta and gamma).
| alpha | beta | gamma |
|---|---|---|
| π/2 | π/2 | π/2 |
The positions of the atoms inside the unit cell are described by the set of atomic positions ( xi, yi, zi) measured from a reference lattice point.
The symmetry properties of the crystal are described by the concept of space groups. All possible symmetric arrangements of particles in three-dimensional space are described by the 230 space groups (219 distinct types, or 230 if chiral copies are considered distinct.
| Space Group Name | Fm_ 3m |
| Space Group Number | 225 |
| Crystal Structure | Face Centered Cubic |
| Number of atoms per unit cell | 4 |
The number of atoms per unit cell in a simple cubic, face-centered cubic and body-centred cubic are 1,4,2 respectively.
Gold Atomic and Orbital Properties
Gold atoms have 79 electrons and the electronic shell structure is [2, 8, 18, 32, 18, 1] with Atomic Term Symbol (Quantum Numbers) 2S1/2.
| Atomic Number | 79 |
| Number of Electrons (with no charge) | 79 |
| Number of Protons | 79 |
| Mass Number | 197 |
| Number of Neutrons | 118 |
| Shell structure (Electrons per energy level) | 2, 8, 18, 32, 18, 1 |
| Electron Configuration | [Xe] 4f14 5d10 6s1 |
| Valence Electrons | 5d10 6s1 |
| Valence (Valency) | 5 |
| Main Oxidation States | 1, 3 |
| Oxidation States | -3, -2, -1, 0, 1, 2, 3, 5 |
| Atomic Term Symbol (Quantum Numbers) | 2S1/2 |
Bohr Atomic Model of Gold - Electrons per energy level
| n | s | p | d | f |
|---|
Ground State Electronic Configuration of Gold - neutral Gold atom
Abbreviated electronic configuration of Gold
The ground state abbreviated electronic configuration of Neutral Gold atom is [Xe] 4f14 5d10 6s1. The portion of Gold configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Xe]. For atoms with many electrons, this notation can become lengthy and so an abbreviated notation is used. This is important as it is the Valence electrons 5d10 6s1, electrons in the outermost shell that determine the chemical properties of the element.
Unabbreviated electronic configuration of neutral Gold
Complete ground state electronic configuration for the Gold atom, Unabbreviated electronic configuration
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s1
Electrons are filled in atomic orbitals as per the order determined by the Aufbau principle, Pauli Exclusion Principle and Hund’s Rule.
As per the Aufbau principle the electrons will occupy the orbitals having lower energies before occupying higher energy orbitals. According to this principle, electrons are filled in the following order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p…
The Pauli exclusion principle states that a maximum of two electrons, each having opposite spins, can fit in an orbital.
Hund's rule states that every orbital in a given subshell is singly occupied by electrons before a second electron is filled in an orbital.
Atomic Structure of Gold
Gold atomic radius is 174 pm, while it's covalent radius is 144 pm.
| Atomic Radius Calculated | 174 pm(1.74 Å) |
| Atomic Radius Empirical | 135 pm (1.35 Å) |
| Atomic Volume | 10.21 cm3/mol |
| Covalent Radius | 144 pm (1.44 Å) |
| Van der Waals Radius | 166 pm |
| Neutron Cross Section | 98.7 |
| Neutron Mass Absorption | 0.017 |
Spectral Lines of Gold - Atomic Spectrum of Gold
A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from an excess or deficiency of photons in a narrow frequency range, compared with the nearby frequencies. Spectral lines are often used to identify atoms and molecules.
Spectral lines are the result of interaction between a quantum system and a single photon. A spectral line may be observed either as an emission line or an absorption line.
Spectral lines are highly atom-specific, and can be used to identify the chemical composition of any medium. Several elements, including helium, thallium, and caesium, were discovered by spectroscopic means. They are widely used to determine the physical conditions of stars and other celestial bodies that cannot be analyzed by other means.
Emission spectrum of Gold
Absorption spectrum of Gold
Gold Chemical Properties: Gold Ionization Energies and electron affinity
The electron affinity of Gold is 222.8 kJ/mol.
| Valence | 5 |
| Electronegativity | 2.54 |
| ElectronAffinity | 222.8 kJ/mol |
Ionization Energy of Gold
Ionization energy is the amount of energy required to remove an electron from an atom or molecule.in chemistry, this energy is expresed in kilocalories per mole (kcal/mol) or kilojoules per mole (kJ/mol).
Refer to table below for Ionization energies of Gold
| Ionization energy number | Enthalpy - kJ/mol |
|---|---|
| 1st | 890.1 |
| 2nd | 1980 |
Gold Physical Properties
Refer to below table for Gold Physical Properties
| Density | 19.3 g/cm3(when liquid at m.p density is $17.31 g/cm3) |
| Molar Volume | 10.21 cm3/mol |
Elastic Properties
| Young Modulus | 78 |
| Shear Modulus | 27 GPa |
| Bulk Modulus | 220 GPa |
| Poisson Ratio | 0.44 |
Hardness of Gold - Tests to Measure of Hardness of Element
| Mohs Hardness | 2.5 MPa |
| Vickers Hardness | 216 MPa |
| Brinell Hardness | 2450 MPa |
Gold Electrical Properties
Electrical resistivity measures element's electrical resistance or how strongly it resists electric current.The SI unit of electrical resistivity is the ohm-metre (Ω⋅m). While Electrical conductivity is the reciprocal of electrical resistivity. It represents a element's ability to conduct electric current. The SI unit of electrical conductivity is siemens per metre (S/m).
Gold is a conductor of electricity. Refer to table below for the Electrical properties of Gold
| Electrical conductors | Conductor |
| Electrical Conductivity | 45000000 S/m |
| Resistivity | 2.2e-8 m Ω |
| Superconducting Point | - |
Gold Heat and Conduction Properties
| Thermal Conductivity | 320 W/(m K) |
| Thermal Expansion | 0.0000142 /K |
Gold Magnetic Properties
| Magnetic Type | Diamagnetic |
| Curie Point | - |
| Mass Magnetic Susceptibility | -1.78e-9 m3/kg |
| Molar Magnetic Susceptibility | -3.51e-10 m3/mol |
| Volume Magnetic Susceptibility | -0.0000344 |
Optical Properties of Gold
| Refractive Index | - |
Acoustic Properties of Gold
| Speed of Sound | 1740 m/s |
Gold Thermal Properties - Enthalpies and thermodynamics
Refer to table below for Thermal properties of Gold
| Melting Point | 1337.33 K(1064.18 °C, 1947.524 °F) |
| Boiling Point | 3129 K(2855.85 °C, 5172.530 °F) |
| Critical Temperature | - |
| Superconducting Point | - |
Enthalpies of Gold
| Heat of Fusion | 12.5 kJ/mol |
| Heat of Vaporization | 330 kJ/mol |
| Heat of Combustion | - |
Gold Isotopes - Nuclear Properties of Gold
Gold has 37 isotopes, with between 169 and 205 nucleons. Gold has 1 stable naturally occuring isotopes.
Isotopes of Gold - Naturally occurring stable Isotopes: 197Au.
| Isotope | Z | N | Isotope Mass | % Abundance | T half | Decay Mode |
|---|---|---|---|---|---|---|
| 169Au | 79 | 90 | 169 | Synthetic | ||
| 170Au | 79 | 91 | 170 | Synthetic | ||
| 171Au | 79 | 92 | 171 | Synthetic | ||
| 172Au | 79 | 93 | 172 | Synthetic | ||
| 173Au | 79 | 94 | 173 | Synthetic | ||
| 174Au | 79 | 95 | 174 | Synthetic | ||
| 175Au | 79 | 96 | 175 | Synthetic | ||
| 176Au | 79 | 97 | 176 | Synthetic | ||
| 177Au | 79 | 98 | 177 | Synthetic | ||
| 178Au | 79 | 99 | 178 | Synthetic | ||
| 179Au | 79 | 100 | 179 | Synthetic | ||
| 180Au | 79 | 101 | 180 | Synthetic | ||
| 181Au | 79 | 102 | 181 | Synthetic | ||
| 182Au | 79 | 103 | 182 | Synthetic | ||
| 183Au | 79 | 104 | 183 | Synthetic | ||
| 184Au | 79 | 105 | 184 | Synthetic | ||
| 185Au | 79 | 106 | 185 | Synthetic | ||
| 186Au | 79 | 107 | 186 | Synthetic | ||
| 187Au | 79 | 108 | 187 | Synthetic | ||
| 188Au | 79 | 109 | 188 | Synthetic | ||
| 189Au | 79 | 110 | 189 | Synthetic | ||
| 190Au | 79 | 111 | 190 | Synthetic | ||
| 191Au | 79 | 112 | 191 | Synthetic | ||
| 192Au | 79 | 113 | 192 | Synthetic | ||
| 193Au | 79 | 114 | 193 | Synthetic | ||
| 194Au | 79 | 115 | 194 | Synthetic | ||
| 195Au | 79 | 116 | 195 | Synthetic | ||
| 196Au | 79 | 117 | 196 | Synthetic | ||
| 197Au | 79 | 118 | 197 | 100% | Stable | |
| 198Au | 79 | 119 | 198 | Synthetic | ||
| 199Au | 79 | 120 | 199 | Synthetic | ||
| 200Au | 79 | 121 | 200 | Synthetic | ||
| 201Au | 79 | 122 | 201 | Synthetic | ||
| 202Au | 79 | 123 | 202 | Synthetic | ||
| 203Au | 79 | 124 | 203 | Synthetic | ||
| 204Au | 79 | 125 | 204 | Synthetic | ||
| 205Au | 79 | 126 | 205 | Synthetic |
Regulatory and Health - Health and Safety Parameters and Guidelines
The United States Department of Transportation (DOT) identifies hazard class of all dangerous elements/goods/commodities either by its class (or division) number or name. The DOT has divided these materials into nine different categories, known as Hazard Classes.
NFPA 704 is a Standard System for the Identification of the Hazards of Materials for Emergency Response. NFPA is a standard maintained by the US based National Fire Protection Association.
The health (blue), flammability (red), and reactivity (yellow) rating all use a numbering scale ranging from 0 to 4. A value of zero means that the element poses no hazard; a rating of four indicates extreme danger.
| NFPA Fire Rating | 0 | Will not burn |
| NFPA Health Rating | 2 | Flash Points Above 37.8°C (100°F) not exceeding 93.3°C (200°F) |
| NFPA Reactivity Rating | 0 | Will not burn |
| NFPA Hazards |
| Autoignition Point | - |
| Flashpoint | - |
Database Search
List of unique identifiers to search the element in various chemical registry databases
| Database | Identifier number |
|---|---|
| CAS Number - Chemical Abstracts Service (CAS) | CAS7440-57-5 |
| RTECS Number | RTECSMD5070000 |
| CID Number | CID23985 |
| Gmelin Number | - |
| NSC Number | - |
Compare Gold with other elements
Compare Gold with Group 11, Period 6 and Transition Metal elements of the periodic table.
Compare Gold with all Group 11 elements
Compare Gold with all Period 6 elements
Compare Gold with all Transition Metal elements
Frequently Asked Questions (FAQ)
Find the answers to the most frequently asked questions about Gold