Aluminum Essay 5

discovery goes to the German scientist, Friedrich Woehler, who in 1827 reacted anhydrous AlCl3 with potassium to isolate aluminum in its pure form. Aluminum is not found free in nature due to its chemically reactive properties. It is found tightly bonded in many compounds.

The main source of aluminum though, is the bauxite ore, also called aluminum oxide (Al2O3). Aluminum is generally obtained by electrolysis of Al2O3. This process includes extracting aluminum oxide from its impurities with a strong base (e. g.sodium hydroxide, NaOH) and then reducing the ore by passing electricity through it. electricity 2Al2O3_-> 4Al + 3O2 The final stage is refining or purifying the crude metal (aluminum).

Because aluminum is tightly bonded to other elements, it requires a lot of energy to extract the metal from its ores. It takes 2 metric tons (t) of aluminum oxide and 17,000 kilowatt hours (kWh) of electricity to produce 1 t of aluminum.

• Aluminum is soft and light. It has a high boiling point of 2467? C and a melting point of 660? C which both contribute to it being a good thermal and electrical conductor.

This metal is nontoxic (as the metal) nonmagnetic and non-sparking.

• Aluminum reacts quickly with oxygen in the air forming a thin, transparent layer of aluminum oxide, which retains its dull grey to silvery appearance.

This oxidation layer over its surface protects it from oxidizing further which therefore makes it slow to corrode. Aluminum is also malleable and ductile (can be drawn out into thin wires) and is a recyclable substance. At high temperatures in a vacuum, aluminum will evaporate and condense onto nearby cool surfaces such as glass or plastic.

Because of this, aluminum

is used to make mirrors, which are better than mirrors made from silver since it does not get black or tarnish like silver when it is exposed to air. Aluminum conducts electricity about 60% as well as copper, which is still very good among metals.Because it is light in weight and highly ductile, it is used instead of copper in almost all of the high-voltage electric transmission lines in the United States.

• Kitchen utensils such as pots and pans are made from aluminum because it is strong but also light.

Due to its strength and flexible properties, aluminum is also used to make foils and cans, which can be recycled. Pure aluminum is relatively soft and not the strongest metal, but its forms very strong alloys which is used in the transport industries, e. g. airplanes and automobiles, because it is light-weight and therefore reduces fuel consumption.One other important use of aluminum is to create dental alloys for teeth filling and denture restorations.

Aluminum has many isotopes with mass numbers ranging from 21 to 41.

• However only two of its isotopes occur naturally: 27Al and 26Al. 27Al is a stable isotope and the most common isotope of aluminum, with a natural occurrence of about 99. 9%. 26

Al has a half-life of 730 000. 0 years and another isotope of aluminum, 28Al has a half-life of 2.3 minutes. ? 26Al is produced from Argon (Ar) in the atmosphere by spallation caused by cosmic-ray protons.Cosmogenic 26Al was first applied in studies of the Moon and meteorites. Meteorite fragments, after departure from their parent bodies, are exposed to intense cosmic-ray bombardment during their travel through space, causing substantial 26Al production.

After

falling to Earth, atmospheric shielding protects the meteorite fragments from further 26 Al production, and its decay can then be used to determine the meteorite's terrestrial age. 8 Aluminum is one of the most useful metals today. It is ideal for many uses since it has such excellent physical and chemical properties.In the US alone, about four million tons are produced yearly; however recent studies have determined links between aluminum intake and certain diseases such as Parkinson’s disease, Alzheimer’s disease and dementia. Although the testing to prove the true association between aluminum and these diseases are inconclusive, scientists have not ruled out high concentration of aluminum as causes for them.

Many organizations are looking into the hypothesis of aluminum being a potential health issue.

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