Aluminium

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Aluminium
13Al
B

Al

Ga
magnesiumaluminiumsilicon
Appearance
sillery gray metallic


Spectral lines o aluminium
General properties
Name, seembol, nummer aluminium, Al, 13
Pronunciation UK Listeni/ˌæljʉˈmɪniəm/
AL-ew-MIN-ee-əm;

US Listeni/əˈljmɨnəm/
ə-LEW-mi-nəm

Element category post-transeetion metal
Group, period, block 13, 3, p
Staundart atomic wicht 26.9815386(13)
Electron confeeguration [Ne] 3s2 3p1
2, 8, 3
Electron shells of aluminium (2, 8, 3)
History
Prediction Antoine Lavoisier[1] (1787)
First isolation Friedrich Wöhler[1] (1827)
Named by Humphry Davy[1] (1807)
Physical properties
Phase solid
Density (near r.t.) 2.70 g·cm−3
Liquid density at m.p. 2.375 g·cm−3
Meltin pynt 933.47 K, 660.32 °C, 1220.58 °F
Boilin pynt 2792 K, 2519 °C, 4566 °F
Heat o fusion 10.71 kJ·mol−1
Heat o vaporization 294.0 kJ·mol−1
Molar heat capacity 24.200 J·mol−1·K−1
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 3, 2[2], 1[3]
(amphoteric oxide)
Electronegativity 1.61 (Pauling scale)
Ionization energies
(more)
1st: 577.5 kJ·mol−1
2nt: 1816.7 kJ·mol−1
3rd: 2744.8 kJ·mol−1
Atomic radius 143 pm
Covalent radius 121±4 pm
Van der Waals radius 184 pm
Miscellanea
Crystal structure face-centered cubic
Aluminium has a face-centered cubic crystal structure
Magnetic orderin paramagnetic[4]
Electrical resistivity (20 °C) 28.2 nΩ·m
Thermal conductivity 237 W·m−1·K−1
Thermal expansion (25 °C) 23.1 µm·m−1·K−1
Speed o soond (thin rod) (r.t.) (rolled) 5,000 m·s−1
Young's modulus 70 GPa
Shear modulus 26 GPa
Bulk modulus 76 GPa
Poisson ratio 0.35
Mohs hairdness 2.75
Vickers hairdness 167 MPa
Brinell hairdness 245 MPa
CAS registry nummer 7429-90-5
Most stable isotopes
Main article: Isotopes o aluminium
iso NA hauf-life DM DE (MeV) DP
26Al trace 7.17×105 y β+ 1.17 26Mg
ε - 26Mg
γ 1.8086 -
27Al 100% 27Al is stable wi 14 neutrons
· r

Aluminium (or aluminum) is a chemical element in the boron group wi seembol Al an atomic nummer 13. It is a sillery white, saft, ductile metal. Aluminium is the third maist abundant element (efter oxygen an silicon), an the maist abundant metal, in the Yird's crust. It maks up aboot 8% bi wicht o the Yird's solid surface. Aluminium metal is so chemically reactive that native specimens are rare an leemitit tae extreme reducing environments. Instead, it is foond combined in ower 270 different minerals.[5] The chief ore o aluminium is bauxite.

Aluminium is remarkable for the metal's law density an for its ability tae resist corrosion due tae the phenomenon o passivation. Structural components made frae aluminium an its alloys are vital tae the aerospace industry an are important in ither auries o transportation an structural materials. The maist uiseful compounds o aluminium, at least on a wicht basis, are the oxides an sulfates.

Despite its prevalence in the environment, aluminium salts are nae kent tae be uised bi ony fairm o life. In keepin wi its pervasiveness, aluminium is well toleratit bi plants an ainimals.[6] Owin tae thair prevalence, potential beneficial (or itherwise) biological roles o aluminium compounds are o continuin interest.

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