New Chemistry for You : Summary

1
Summary Rocks and metals

• Ores are compounds which contain enough metal to
  make it economic to extract the metal.
• Examples of ores include
• Haematite (a source of iron)
• Bauxite (a source of aluminium)
• The economic worthwhile of extracting different
  metals may change over time as the availability
  and market value of the metal changes.

AQA C1a.2 Chapters 4,6,7 and 21
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Summary Rocks and metals

• The Reactivity Series lists metals in order of
  reactivity.
• A more reactive metal can displace a less
  reactive metal from its compounds. For
  examplecopper oxide zinc ? zinc oxide
  copper
• Metals less reactive than carbon can be extracted
  from their ores by reduction with carbon. For
  example
• carbon iron oxide ? carbon dioxide iron

AQA C1a.2 Chapters 4,6,7 and 21
3
Summary Rocks and metals

• The way we extract a metal from its ore depends
  on its place in the Reactivity Series. The more
  reactive a metal is, the harder it is to extract.
• Iron oxide is reduced to iron in a Blast furnace.
  
• The iron produced in the furnace contains 90
  pure iron, the impurities present make the iron
  brittle and this restricts its use.
• Most of the iron produced from the Blast furnace
  is then changed into steel. Steel is an alloy of
  iron, carbon and other metals.

AQA C1a.2 Chapters 4,6,7 and 21
4
Summary Rocks and metals

• Alloys are often stiffer, stronger and harder
  than the pure metal itself. These properties
  relate to specific uses of alloys. Examples of
  alloys include
• Brass
• Bronze
• Steel (low carbon and high carbon)
• Stainless steel
• Gold, copper and aluminum may also be alloyed to
  make them harder.

AQA C1a.2 Chapters 4,6,7 and 21
5
Summary Rocks and metals

• The Transition metals are found in the central
  block of Periodic table. They have properties
  typical of other metals, they
• are hard and dense, with high melting points
• are less reactive than Group 1 or Group 2 metals
• form coloured compounds
• can form compounds with more than one formula,
  for example, iron(II) oxide, and iron(III) oxide.
• are important catalysts in industry.
• can be hammered or bent into shape
• are good conductors of heat and electricity

AQA C1a.2 Chapters 4,6,7 and 21
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Summary Rocks and metals

• Copper is a very useful transition metal. The
  properties of copper make it especially useful
  for electrical wiring and plumbing.
• Copper is purified by a process called
  electrolysis.
• Since the supply of copper rich ores is limited,
  research is being undertaken to enable copper to
  be extracted from low grade ores. This will also
  limit the environmental impact of traditional
  mining methods.

AQA C1a.2 Chapters 4,6,7 and 21
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Summary Rocks and metals

• Aluminium and titanium are metals with low
  densities, they are also corrosion resistant.
• When alloyed, aluminum is useful for making
  aircraft frames, step-ladders, drinks cans and
  food containers.
• Titanium alloys may be used in turbine engine
  parts, surgical implants, heat exchanges and
  rocket motor casings.
• Aluminium and titanium cannot be extracted from
  their ores using carbon. The methods used to
  extract these metals however, are expensive.

AQA C1a.2 Chapters 4,6,7 and 21
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Summary Rocks and metals

• Steel and aluminium are two of the most common
  metals used in the UK .
• Metals can be recycled indefinitely without
  loosing any of their properties. They make up
  around 8 of the average household dustbin.
• If metals are recycled, our limited resources
  will last longer and the effects on the
  environment will be reduced.
• Recycling metals, compared to extracting them,
  will save considerable energy costs!

AQA C1a.2 Chapters 4,6,7 and 21
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