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Aluminum is the most abundant metal in the earth's crust.
Aluminum is a silver colored, lightweight metal. Its atomic weight
is 26.9815. Aluminum is also extremely reactive. Aluminum is
covered in a layer of aluminum oxide which resists coffosion
because all things made of aluminum don't rust or tarnish. It
reduces many other metal compounds to their base metals. |
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Aluminum is only outnumbered by the nonmetals oxygen and silicon. It is never found as a free metal. The silicates of aluminum are not useful ores. Bauxite is the commercial source of aluminum. The Hall-Heroult process, a low-cost tequnique that reduces aluminum to a crude molten metal, is the major method of commercially producing aluminum. Aluminum in a commercially pure form is about 99.5% pure, but it can further be purified to 99.99% pure.
Aluminum has a high heat conductivity, and because of this, it can be used in kitchen utensils and the pistons of internal-combustion engines. It can also be used in cars, planes, and train cars because of its light weight. Aluminum is becoming important in architecture for constructional and decorative purposes. Aluminum is a good insulator, so it is used for siding, foil, and storm windows. It gets stronger as it gets colder, therefore it is used at cryogenic temperature. Aluminum also resists corrosion in water, so it is used for boat hulls.
