Using Metals (Edexcel GCSE Chemistry): Revision Note

Using Metals

Aluminium Alloys

• Aluminium is mixed with copper, manganese and silicon for aircraft body production as aluminium alloys tend to be stronger and lighter than pure aluminium

• Aluminium and magnesium (5%) make an interesting alloy called magnalium which is also used extensively in automobile and aircraft construction

• As well as being lighter and stronger, it is also more corrosion resistant than aluminium.

• Magnalium with 50% magnesium is used in the production of fireworks as it is more stable than pure magnesium but still burns brightly

Uses of Aluminium

Copper Alloys

• Bronze is an alloy made of copper and tin. It is harder than copper and is used to make ornaments and medals

• Brass is a common example of an alloy which contains 70% copper and 30% zinc. It is decorative and corrosion resistant and is used for low friction ornamental purposes such as plumbing and carpentry fittings

Brass is used extensively in modern kitchen and bathroom fittings

Uses of Copper

Gold Alloys

• Gold alloys are used to make jewellery

• Gold metal is relatively soft and malleable so other metals such as copper, zinc and silver are added to provide strength and toughness

• Carats are used to express the purity of gold jewellery

• Pure gold with nothing else added is said to be 24 carat

• A 12 carat piece of gold jewellery therefore contains 50% gold

• For example a 12 carat necklace that weighs 50 g contains 25 grams of gold

Rose, yellow and white gold are alloys of gold with varying proportions of copper, silver and other metals. White gold is a good imitation of platinum which is a very expensive precious metal