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Aluminium[Al]
Atomic Number: 13
Atomic Weight: 26.981539
Discovery: Hans Christian Oersted (1825 Denmark), Wohler (1827)
Word Origin: Latin alumen: alum, an astringent and dyeing mordant
Properties1. Aluminum has a melting point of 660.37°C, 2. It has a boiling point of 2467°C, specific gravity of 2.6989 (20°C),3. Aluminium has a valence of 3. 4. Pure aluminum is a silvery-white metal. 5. It is soft, light, relatively nontoxic, with a high thermal conductivity, 6. high corrosion resistance. It can be easily formed, machined, or cast. 7. Aluminum is nonmagnetic and nonsparking. 8. second among metals in terms of malleability and sixth in ductility.9. Aluminum coatings are highly reflective of both visible and radiant heat. 10. The coatings form a thin layer of protective oxide and do not deteriorate like silver coatings.
Uses of aluminium
Further UsesAncient Greeks and Romans used alum as an astringent, for medicinal purposes, and as a mordant in dyeing. It is used in kitchen utensils, exterior decorations, and thousands of industrial applications. aluminum is used in electrical transmission lines because of its light weight. The alloys of aluminum are used in the construction of aircraft and rockets. Reflective aluminum coatings are used for telescope mirrors, making decorative paper, packaging, and many other uses. Alumina is used in glassmaking and refractories. Synthetic ruby and sapphire have applications in producing coherent light for lasers.
Aluminium FactsAluminum was once called the "Metal of Kings" because pure aluminum was more expensive to produce than gold until the Hall-Heroult process was discovered.The primary source of aluminum is the ore bauxite.Aluminum is paramagnetic.The IUPAC adopted the name Aluminium in 1990 and in 1993 recognized aluminum as an acceptable option for the element's name.
Charles HallPaul Héroult
Extraction
In the early 19th century,
The modern method of Aluminium extraction was discovered
independently by two scientists in 1886.
It greatly decreased the cost of producing Aluminium, making it easily
commercially available.
Laying the capstone of the Washington
Monument in 1884. At the time it was more valuable than silver.
Two years later the cap was almost
worthless.
Molten alumina with electrolytic cryoliteGraphitecathode
Al
AlAlGraphiteanode
CC C
O
O O
O
O
O
AlAl
C
O
O
C
O
O
C
O
O
2Al2O3(aq) + 3C(s) 4Al(l) + 3CO2(g)
Alumina Carbon Aluminium Carbon dioxide
Na3AlF6(aq)
Cryolite