2. 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

3. The Reactivity Series lists metals in order of reactivity. A more reactive metal can displace a less reactive metal from its compounds. For example: copper 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 Summary : Rocks and metals

4. 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 Summary : Rocks and metals

5. 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 Summary : Rocks and metals

6. 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 Summary : Rocks and metals

7. 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 Summary : Rocks and metals

8. 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 Summary : Rocks and metals

9. 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 Summary : Rocks and metals