Aluminum

Unsur kimia, nomor atom 13, lambang Al.

Merriam-Webster Online Dictionary
aluminum (noun)
a bluish silver-white malleable ductile light trivalent metallic element that has good electrical and thermal conductivity, high reflectivity, and resistance to oxidation and is the most abundant metal in the earth's crust where it always occurs in combination - see element table
Aluminum (Wikipedia)
Aluminium,  13Al
Aluminium-4.jpg
Aluminum Spectra.jpg
Spectral lines of aluminium
General properties
Pronunciation UK: Listeni/ˌæljᵿˈmɪniəm/
AL-ew-MIN-ee-əm
US: Listeni/əˈljmnəm/
ə-LEW-mi-nəm
Alternative name aluminum (US, informal)
Appearance silvery gray metallic
Aluminium in the periodic table
Hydrogen (diatomic nonmetal)
Helium (noble gas)
Lithium (alkali metal)
Beryllium (alkaline earth metal)
Boron (metalloid)
Carbon (polyatomic nonmetal)
Nitrogen (diatomic nonmetal)
Oxygen (diatomic nonmetal)
Fluorine (diatomic nonmetal)
Neon (noble gas)
Sodium (alkali metal)
Magnesium (alkaline earth metal)
Aluminium (post-transition metal)
Silicon (metalloid)
Phosphorus (polyatomic nonmetal)
Sulfur (polyatomic nonmetal)
Chlorine (diatomic nonmetal)
Argon (noble gas)
Potassium (alkali metal)
Calcium (alkaline earth metal)
Scandium (transition metal)
Titanium (transition metal)
Vanadium (transition metal)
Chromium (transition metal)
Manganese (transition metal)
Iron (transition metal)
Cobalt (transition metal)
Nickel (transition metal)
Copper (transition metal)
Zinc (transition metal)
Gallium (post-transition metal)
Germanium (metalloid)
Arsenic (metalloid)
Selenium (polyatomic nonmetal)
Bromine (diatomic nonmetal)
Krypton (noble gas)
Rubidium (alkali metal)
Strontium (alkaline earth metal)
Yttrium (transition metal)
Zirconium (transition metal)
Niobium (transition metal)
Molybdenum (transition metal)
Technetium (transition metal)
Ruthenium (transition metal)
Rhodium (transition metal)
Palladium (transition metal)
Silver (transition metal)
Cadmium (transition metal)
Indium (post-transition metal)
Tin (post-transition metal)
Antimony (metalloid)
Tellurium (metalloid)
Iodine (diatomic nonmetal)
Xenon (noble gas)
Caesium (alkali metal)
Barium (alkaline earth metal)
Lanthanum (lanthanide)
Cerium (lanthanide)
Praseodymium (lanthanide)
Neodymium (lanthanide)
Promethium (lanthanide)
Samarium (lanthanide)
Europium (lanthanide)
Gadolinium (lanthanide)
Terbium (lanthanide)
Dysprosium (lanthanide)
Holmium (lanthanide)
Erbium (lanthanide)
Thulium (lanthanide)
Ytterbium (lanthanide)
Lutetium (lanthanide)
Hafnium (transition metal)
Tantalum (transition metal)
Tungsten (transition metal)
Rhenium (transition metal)
Osmium (transition metal)
Iridium (transition metal)
Platinum (transition metal)
Gold (transition metal)
Mercury (transition metal)
Thallium (post-transition metal)
Lead (post-transition metal)
Bismuth (post-transition metal)
Polonium (post-transition metal)
Astatine (metalloid)
Radon (noble gas)
Francium (alkali metal)
Radium (alkaline earth metal)
Actinium (actinide)
Thorium (actinide)
Protactinium (actinide)
Uranium (actinide)
Neptunium (actinide)
Plutonium (actinide)
Americium (actinide)
Curium (actinide)
Berkelium (actinide)
Californium (actinide)
Einsteinium (actinide)
Fermium (actinide)
Mendelevium (actinide)
Nobelium (actinide)
Lawrencium (actinide)
Rutherfordium (transition metal)
Dubnium (transition metal)
Seaborgium (transition metal)
Bohrium (transition metal)
Hassium (transition metal)
Meitnerium (unknown chemical properties)
Darmstadtium (unknown chemical properties)
Roentgenium (unknown chemical properties)
Copernicium (transition metal)
Nihonium (unknown chemical properties)
Flerovium (unknown chemical properties)
Moscovium (unknown chemical properties)
Livermorium (unknown chemical properties)
Tennessine (unknown chemical properties)
Oganesson (unknown chemical properties)
B

Al

Ga
magnesiumaluminiumsilicon
Atomic number (Z) 13
Group, period group 13 (boron group), period 3
Block p-block
Element category   post-transition metal, sometimes considered a metalloid
Standard atomic weight (Ar) 26.9815385(7)
Electron configuration [Ne] 3s2 3p1
Electrons per shell
2, 8, 3
Physical properties
Phase solid
Melting point 933.47 K ​(660.32 °C, ​1220.58 °F)
Boiling point 2743 K ​(2470 °C, ​4478 °F)
Density near r.t. 2.70 g/cm3
when liquid, at m.p. 2.375 g/cm3
Heat of fusion 10.71 kJ/mol
Heat of vaporization 284 kJ/mol
Molar heat capacity 24.20 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 +3, +2, +1, −1, −2 ​(an amphoteric oxide)
Electronegativity Pauling scale: 1.61
Ionization energies 1st: 577.5 kJ/mol
2nd: 1816.7 kJ/mol
3rd: 2744.8 kJ/mol
(more)
Atomic radius empirical: 143 pm
Covalent radius 121±4 pm
Van der Waals radius 184 pm
Miscellanea
Crystal structure face-centered cubic (fcc)
Face-centered cubic crystal structure for aluminium
Speed of sound thin rod (rolled) 5000 m/s (at r.t.)
Thermal expansion 23.1 µm/(m·K) (at 25 °C)
Thermal conductivity 237 W/(m·K)
Electrical resistivity 28.2 nΩ·m (at 20 °C)
Magnetic ordering paramagnetic
Magnetic susceptibility (χmol) +16.5·10−6 cm3/mol
Young's modulus 70 GPa
Shear modulus 26 GPa
Bulk modulus 76 GPa
Poisson ratio 0.35
Mohs hardness 2.75
Vickers hardness 160–350 MPa
Brinell hardness 160–550 MPa
CAS Number 7429-90-5
History
Prediction Antoine Lavoisier(1787)
Discovery and first isolation Hans Christian Ørsted (1825)
Named by Humphry Davy(1807)
Main isotopes of aluminium
Iso­tope Abun­dance Half-life Decay mode Pro­duct
26Al trace 7.17×105 y β+ 26Mg
ε 26Mg
γ
27Al 100% is stable with 14 neutrons
| references | in Wikidata

Aluminium or aluminum (see below) is a chemical element in the boron group with symbol Al and atomic number 13. It is a silvery-white, soft, nonmagnetic, ductile metal. By mass, aluminium makes up about 8% of the Earth's crust; it is the third most abundant element after oxygen and silicon and the most abundant metal in the crust, though it is less common in the mantle below. Aluminium metal is so chemically reactive that native specimens are rare and limited to extreme reducing environments. Instead, it is found combined in over 270 different minerals. The chief ore of aluminium is bauxite.

Aluminium is remarkable for the metal's low density and its ability to resist corrosion through the phenomenon of passivation. Aluminium and its alloys are vital to the aerospace industry and important in transportation and building industries, such as building facades and window frames. The oxides and sulfates are the most useful compounds of aluminium.

Despite its prevalence in the environment, no known form of life uses aluminium salts metabolically, but aluminium is well tolerated by plants and animals. Because of these salts' abundance, the potential for a biological role for them is of continuing interest, and studies continue.