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Oxidation & Electrons | Appearance & Characteristics Reactions | Compounds | Radius | Conductivity Abundance & Isotopes 
Aluminum foil. |
General:
| Name: Aluminum | Symbol: Al |
| Type: Metal | Atomic weight: 26.98154 |
| Density @ 293 K: 2.702 g/cm3 | Atomic volume: 9.98 cm3/mol |
| Discovered: Aluminum was first isolated in 1825 by Hans Christian Oersted who reported, "a lump of metal which in color and luster somewhat resembles tin". | |
States
| State (s, l, g): solid | |
| Melting point: 933.57 K (660.32 oC) | Boiling point: 2740 K (2466.85 oC) |
Energies
| Specific heat capacity: 0.90 J g-1 K-1 | Heat of atomization: 326 kJ mol-1 |
| Heat of fusion: 10.790 kJ mol-1 | Heat of vaporization: 293.40 kJ mol-1 |
| 1st ionization energy: 577.6 kJ mol-1 | 2nd ionization energy: 1816.6 kJ mol-1 |
| 3rd ionization energy: 2744.7 kJ mol-1 | Electron affinity: 42.6 kJ mol-1 |
Oxidation & Electrons
| Shells: 2,8,3 | Electron configuration: [Ne] 3s2 3p1 |
| Minimum oxidation number: 0 | Maximum oxidation number: 3 |
| Min. common oxidation no.: 0 | Max. common oxidation no.: 3 |
| Electronegativity (Pauling Scale): 1.61 | Polarizability volume: 8.3 Å3 |
Appearance & Characteristics
| Structure: fcc: face-centered cubic | Color: silvery |
| Harmful effects: No proven issues; ingestion may cause alzheimer's disease | Hardness: 2.8 mohs |
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An aluminum block is cut, it's like a hot knife through butter.
Pouring molten aluminum.
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Characteristics: Excellent electrical conduction, low density, ductile, non-magnetic, silvery-white metal. Aluminum's appearance is dulled and its reactivity is passivated by a film of aluminum oxide which naturally forms on the surface of the metal under normal conditions. The oxide film results in a material that resists corrosion. Aluminum lies sufficiently far on the right side of the periodic table that it shows some hints of nonmetal behavior, reacting with hot alkalis to form aluminate ions [Al(OH)4]- as well as the more typical metal reaction with acids to release hydrogen gas and form the positively charged metal ion, Al3+. i.e. aluminum is amphoteric. Uses: As a result of its low density, low cost, and corrosion resistance, aluminum is widely used around the world. It is used in an extensive range of products from drinks cans to window frames and boats to aircraft. A Boeing 747-400 contains 147,000 pounds (66,150 kg) of high-strength aluminum. Unlike some metals, aluminum has no aroma - hence its widespread use in food packaging and cooking pots. Although not quite as good as silver or copper, aluminum is an excellent electrical conductor. It is also considerably cheaper and lighter than these metals, so it is used widely in overhead power lines. Of all the metals, only iron is used more widely than aluminum. |
Reactions
| Reaction with air: mild, w/ht ⇒ Al2O3 | Reaction with 6 M HCl: mild, ⇒ H2, AlCl3 |
| Reaction with 15 M HNO3: passivated | Reaction with 6 M NaOH: mild, ⇒ H2, [Al(OH)4]- |
Compounds
| Oxide(s): Al2O3 | Chloride(s): AlCl3 & Al2Cl6 |
| Hydride(s): AlH3 |
Radius
| Atomic radius: 125 pm | Ionic radius (1+ ion): pm |
| Ionic radius (2+ ion): pm | Ionic radius (3+ ion): 53.5 pm |
| Ionic radius (2- ion): pm | Ionic radius (1- ion): pm |
Conductivity
| Thermal conductivity: 237 W m-1 K-1 | Electrical conductivity: 37.6676 x 106 S m-1 |
Abundance & Isotopes
| Abundance earth's crust: 8.2 % by weight, 6.3 % by moles | |
| Abundance solar system: 56 ppm by weight, 2.7 ppm by moles | |
| Cost, pure: 1.8 $/100g | |
| Cost, bulk: 0.12 $/100g | |
| Source: Aluminum is the third most abundant element in the earth's crust, but is too reactive to be found pure. Bauxite (manily aluminum oxide) is the most important ore. | |
| Isotopes: 15 whose half-lives are known, mass numbers 22 to 35. Of these, only two occur naturally: 27Al, which is stable, and 26Al, which is radioactive with half-life is 7.17 x 105 years. 26Al is formed by cosmic-ray bombardment of argon in earth's atmosphere. | |
