1. Uses of aluminium
Aluminium is a light, strong metal and has good electrical conductivity. Increasingly, aluminium is used for construction purposes. It is used in the construction of some nail vessels and modern cars. It is commonly used in airplanes, where it is usually alloyed with other metals such as copper. Its low density and good conductivity have also lead to its use in overhead power lines. The aluminium is very resistant to corrosion and its low density prevents sagging pf the cables between pylons.
Aluminium is particularly useful because it is protected from corrosion by the stable layer of aluminium oxide that forms on its surface. This protective layer stops the aluminium from reacting. This makes aluminium foil containers ideal for food packaging because they resist corrosion by natural acids present in the food. Aluminium is also used for external structures such as window frames because the metals resists weathering.
2. Uses of copper
Copper has a very high electrical conductivity and is very ductile, and so can be easily drawn out as wire. A major use of copper s in electrical ables and domestic wiring. It is also used in the circuit boards of smartphones and other electronic equipment. The copper used for wiring and circuit boards must be of high purity or the electrical conductivity will be reduced significantly. This is why copper is refined to very purity by electrolysis.
3. Summary
- aluminium in the manufacture of aircraft because of its low density
- aluminium in the manufacture of overhead electrical cables because of its low density and good electrical conductivity
- aluminium in food containers because of its resistance to corrosion
- copper in electrical wiring because of its good electrical conductivity and ductility
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