Aluminium

« Back to Glossary Index

**Physical Characteristics of Aluminium:**
– Aluminium is a chemical element with symbol Al and atomic number 13.
– It has a density about one-third that of steel.
– Aluminium forms a protective oxide layer when exposed to air.
– It visually resembles silver and is soft, nonmagnetic, and ductile.
– Aluminium has one stable isotope, Al, making it the twelfth-most common element in the universe.
– An aluminium atom has 13 electrons in an electron configuration of Ne 3s.
– Aluminium can surrender its three outermost electrons in chemical reactions.
– The electronegativity of aluminium is 1.61.
– A free aluminium atom has a radius of 143pm.
– Aluminium metal appears silvery white to dull gray.
– Aluminium mirrors are highly reflective in various light spectra.
– Aluminium is good at reflecting solar radiation.
– The density of aluminium is 2.70g/cm.
– Anodizing aluminium adds a protective oxide layer to prevent wear.

**Isotopes and Electron Shell of Aluminium:**
– Only Al is stable among aluminium isotopes.
– Al is the only primordial aluminium isotope on Earth since the planet’s formation.
– Other aluminium isotopes are radioactive, with Al having a half-life of 717,000 years.
– Minute traces of Al are produced from argon in the atmosphere.
– Al isotopes have been used for radiodating geological processes.
– Aluminium atoms form a face-centered cubic crystal system under standard conditions.

**Discovery and Industrial Use of Aluminium:**
– Aluminium was discovered in 1825 by Hans Christian Ørsted.
– Industrial production began in 1856 by Henri Étienne Sainte-Claire Deville.
– The Hall–Héroult process led to mass production in 1886.
– Aluminium was crucial in World Wars I and II for aviation.
– In 1954, aluminium became the most produced non-ferrous metal.

**Chemistry and Compounds of Aluminium:**
– Combines characteristics of pre- and post-transition metals.
– Strongly polarizing and bonding in compounds tends towards covalency.
– Most electropositive metal in its group.
– Forms icosahedral quasicrystal alloys.
– Used as a reducing agent in the thermite reaction.
– Most compounds feature aluminium in oxidation state 3+.
– Coordination number of compounds is generally six- or four-coordinate.
– Almost all compounds of aluminium(III) are colorless.
– Forms salts and aluminates, dissolves in acid and alkali.
– Aluminium trichloride used as a catalyst in industrial reactions.

**Global Impact and Production of Aluminium:**
– Production costs lowered over technological progress and economies of scale.
– BRIC countries share in primary production and consumption grew substantially.
China accumulated a large share of global production and consumption.
– Most aluminium consumed in transportation, engineering, construction, and packaging in the US, Western Europe, and Japan.
– Industrial metal prices, including aluminium, soared in 2021 due to energy shortages in China.
– Aluminium production surpassed copper in 1954.
– Aluminium widely used in civil engineering and military applications.
– World production of aluminium exceeded 50,000,000 metric tons in 2013.
– Bauxite is processed into alumina using the Bayer process.
– The Hall–Héroult process is used to produce aluminium metal.

Aluminium (Wikipedia)

Aluminium (Aluminum in North American English) is a chemical element; it has symbol Al and atomic number 13. Aluminium has a density lower than that of other common metals, about one-third that of steel. It has a great affinity towards oxygen, forming a protective layer of oxide on the surface when exposed to air. Aluminium visually resembles silver, both in its color and in its great ability to reflect light. It is soft, nonmagnetic, and ductile. It has one stable isotope, 27Al, which is highly abundant, making aluminium the twelfth-most common element in the universe. The radioactivity of 26Al, a more unstable isotope, leads to it being used in radiometric dating.

Aluminium, 13Al
Aluminium
Pronunciation
Alternative nameAluminum (U.S., Canada)
AppearanceSilvery gray metallic
Standard atomic weight Ar°(Al)
  • 26.9815384±0.0000003
  • 26.982±0.001 (abridged)
Aluminium in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
B

Al

Ga
magnesiumaluminiumsilicon
Atomic number (Z)13
Groupgroup 13 (boron group)
Periodperiod 3
Block  p-block
Electron configuration[Ne] 3s2 3p1
Electrons per shell2, 8, 3
Physical properties
Phase at STPsolid
Melting point933.47 K ​(660.32 °C, ​1220.58 °F)
Boiling point2743 K ​(2470 °C, ​4478 °F)
Density (at 20° C)2.699 g/cm3
when liquid (at m.p.)2.375 g/cm3
Heat of fusion10.71 kJ/mol
Heat of vaporization284 kJ/mol
Molar heat capacity24.20 J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 1482 1632 1817 2054 2364 2790
Atomic properties
Oxidation states−2, −1, 0, +1, +2, +3 (an amphoteric oxide)
ElectronegativityPauling scale: 1.61
Ionization energies
  • 1st: 577.5 kJ/mol
  • 2nd: 1816.7 kJ/mol
  • 3rd: 2744.8 kJ/mol
  • (more)
Atomic radiusempirical: 143 pm
Covalent radius121±4 pm
Van der Waals radius184 pm
Color lines in a spectral range
Spectral lines of aluminium
Other properties
Natural occurrenceprimordial
Crystal structureface-centered cubic (fcc) (cF4)
Lattice constant
Face-centered cubic crystal structure for aluminium
a = 404.93 pm (at 20 °C)
Thermal expansion22.87×10−6/K (at 20 °C)
Thermal conductivity237 W/(m⋅K)
Electrical resistivity26.5 nΩ⋅m (at 20 °C)
Magnetic orderingparamagnetic
Molar magnetic susceptibility+16.5×10−6 cm3/mol
Young's modulus70 GPa
Shear modulus26 GPa
Bulk modulus76 GPa
Speed of sound thin rod(rolled) 5000 m/s (at r.t.)
Poisson ratio0.35
Mohs hardness2.75
Vickers hardness160–350 MPa
Brinell hardness160–550 MPa
CAS Number7429-90-5
History
Namingfrom alumine, obsolete name for alumina
PredictionAntoine Lavoisier (1782)
DiscoveryHans Christian Ørsted (1824)
Named byHumphry Davy (1812)
Isotopes of aluminium
Main isotopes Decay
abun­dance half-life (t1/2) mode pro­duct
26Al trace 7.17×105 y β+84% 26Mg
ε16% 26Mg
γ
27Al 100% stable
 Category: Aluminium
| references

Chemically, aluminium is a post-transition metal in the boron group; as is common for the group, aluminium forms compounds primarily in the +3 oxidation state. The aluminium cation Al3+ is small and highly charged; as such, it has more polarizing power, and bonds formed by aluminium have a more covalent character. The strong affinity of aluminium for oxygen leads to the common occurrence of its oxides in nature. Aluminium is found on Earth primarily in rocks in the crust, where it is the third-most abundant element, after oxygen and silicon, rather than in the mantle, and virtually never as the free metal. It is obtained industrially by mining bauxite, a sedimentary rock rich in aluminium minerals.

The discovery of aluminium was announced in 1825 by Danish physicist Hans Christian Ørsted. The first industrial production of aluminium was initiated by French chemist Henri Étienne Sainte-Claire Deville in 1856. Aluminium became much more available to the public with the Hall–Héroult process developed independently by French engineer Paul Héroult and American engineer Charles Martin Hall in 1886, and the mass production of aluminium led to its extensive use in industry and everyday life. In the First and Second World Wars, aluminium was a crucial strategic resource for aviation. In 1954, aluminium became the most produced non-ferrous metal, surpassing copper. In the 21st century, most aluminium was consumed in transportation, engineering, construction, and packaging in the United States, Western Europe, and Japan.

Despite its prevalence in the environment, no living organism is known to metabolize aluminium salts, but this aluminium is well tolerated by plants and animals. Because of the abundance of these salts, the potential for a biological role for them is of interest, and studies are ongoing.


« Back to Glossary Index