Aluminum combines low density, electrical conductivity, and resistance to corrosion. It is used in packaging, power lines, and transport, often alloyed with other elements to improve strength. Its reflective coatings also appear on telescope mirrors, connecting everyday foil to precision optical instruments.
FROM ELEMENT TO APPLICATION
AN ELEMENT IN CONTEXT
How does aluminum alloying help turn a light metal into a transport structure?
Aluminum alloys containing other metals
FOLLOW THIS RELATIONSHIP
Identify a structural requirement
An aircraft or vehicle part must sustain specified loads; pure aluminum's low density does not alone provide the required combination of mechanical properties.
Explore the model (optional)
AlFORM → INTERACTION → CONSEQUENCE
Follow the explanation in either direction. These are authored steps, not a physical clock.
Aluminum's compounds were familiar before the metal could be separated from them. Hans Christian Ørsted prepared a sample in 1825, and Friedrich Wöhler improved the preparation in 1827. Investigations established the metal in alumina and other . The story illustrates a recurring distinction in elemental history: knowing a compound exists does not immediately provide a method for obtaining its constituent element.
1825
Early sample prepared
Ørsted obtained aluminum through chemical reduction of an aluminum compound.
1827
Preparation improved
Wöhler developed the experimental preparation further and studied the metal.
Aluminum occurs chemically combined in many minerals, including aluminosilicates. Aluminum forms the mineral corundum; small amounts of other elements produce the colors associated with ruby and sapphire. Natural aluminum-bearing materials therefore include both rock-forming minerals and gemstones, with properties governed by composition and structure.
Aluminum is a lightweight, electrically conductive metal. A thin surface oxide helps protect it from further attack in many everyday conditions, although protection depends on the environment. Adding other metals changes its mechanical properties, explaining why structural aluminum products often use rather than the pure element.
Each section links its supporting references. Descriptions and diagrams were authored for this atlas. Source checks completed. Source checks dated 2026-09-06.
CITE THIS PAGE
Family labels and the group-3 layout are teaching conventions. A table position does not establish an unknown bulk property. Electronic configurations refer to neutral atoms; ions and material environments require their own account.
Read each reference property together with its units, conditions and the reference information below.
Not yet recorded: electron affinity, second ionization energy, ground-state term symbol, van der waals radius, thermal conductivity, specific heat capacity, electrical resistivity, crystal structure, lattice parameter a, space group, abundance in seawater, abundance in the universe, annual production, supply-risk listing, hazard classification, biological role, cas registry number, pubchem cid, wikidata item. These families are declared and awaiting an ingestion run against the source each names; they are listed here rather than shown as empty rows.
Physical
Intended reference: CRC Handbook of Chemistry and Physics · CRC Press
Phase at 20 °C
solid
293.15 K, 101.325 kPa
Melting point in K
933.47 K
at standard pressure unless noted
Boiling point in K
2792 K
101.325 kPa
Density in g/cm³
2.7 g/cm³
solids and liquids at 293 K; gases at 273 K and 101.325 kPa
Atomic and electronic
Intended reference: Pauling electronegativity scale · Widely tabulated; original in The Nature of the Chemical Bond
Electronegativity in Pauling
1.61 Pauling
Pauling scale
First ionization energy in kJ/mol
577.5 kJ/mol
gas-phase neutral atom, ground state
Covalent radius in pm
121 pm
single-bond covalent radius
Common oxidation states
+3
states met in ordinary compounds; not exhaustive
Occurrence and identity
Intended reference: CRC Handbook of Chemistry and Physics · CRC Press
Abundance in the crust in mg/kg
82300 mg/kg
upper continental crust, mass fraction
Has stable isotopes
Yesderived
Discovery year in CE
1825 CEderived
WHERE IT SITS AMONG ITS NEIGHBORS
Electronegativity across period 3
Al 1.61 Pauling · Aluminum
Electronegativity across period 3. Exact values.
Na
0.93
Mg
1.31
Al
1.61
Si
1.9
P
2.19
S
2.58
Cl
3.16
Electronegativity down group 13
Al 1.61 Pauling · Aluminum
Electronegativity down group 13. Exact values.
B
2.04
Al
1.61
Ga
1.81
In
1.78
Tl
1.62
The trend uses the same reference-property values as the periodic table. Elements with no recorded value are left out of the line rather than drawn at zero.
