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| Properties and Uses of Aluminium |
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 A bluish white metal. Light but strong and has a low density |
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Resistant to corrosion and can be easily bent and shaped |
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Good conductor of heat and electricity |
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Can be polished to achieve a highly reflective surface |
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Boiling point 2050ºC and melting point 660ºC |
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Despite being high in the reactivity series, aluminium is resistant to corrosion because of the thin layer of aluminium oxide  which forms on its surface in air. The oxide layer protects the metal beneath and renders it inert to any further reaction. |
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The thin oxide layer will react with an acid or alkali to form the corresponding aluminium salt and water. The exposed aluminium metal will then further react with acid or alkali to form the aluminium salt and hydrogen. For this reason, aluminium cookware should not be allowed to come into prolonged contact with citrus fruits or vinegar (acids), or alkali cleaners such as caustic soda (sodium hydroxide). Aluminium in food is a health hazard and has been associated with Alzheimer's disease. |
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| Aluminium liberates hydrogen on reaction with dilute sulphuric acid. Suphur dioxide is liberated on reaction with concentrated sulphuric acid. |
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| With dilute or concentrated nitric acid aluminium is rendered passive due to the formation of aluminium oxide layer. |
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| Aluminium reacts with non-metals forming aluminium chloride and sulphide. |
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| Aluminium reduces heated metallic oxides of Fe, Cr, Mn to metals |
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Low density and strength make it ideal for construction of aircraft, lightweight vehicles, and ladders. |
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An alloy of aluminium called duralumin is often used instead of pure aluminium because of its improved properties. |
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Easy shaping and corrosion resistance make it a good material for drink cans and roofing materials. |
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Corrosion resistance and low density leads to its use for greenhouses and window frames. |
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Good conduction of heat leads to its use for boilers, cookers and cookware. |
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Good conduction of electricity leads to its use for overhead power cables hung from pylons (a tall structure erected as a support esp. for electric power cables or boundary or decoration). The low density gives it an advantage over copper. |
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High reflectivity makes it ideal for mirrors, reflectors and heat resistant clothing for fire fighting. |
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