C1 Metals and their uses
- Created by: Hollie Wickens
- Created on: 19-03-14 10:32
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- Metals and their uses
- Extracting metals
- A metal ore is a rock which contains enough metal to make it worthwhile extracting the metal from it
- In many cases the ore is an oxide of the metal (e.g. the main aluminium ore is bauxite, which is aluminium oxide)
- Most metals need to be extracted from their ores using a chemical reaction
- A metal ore is a rock which contains enough metal to make it worthwhile extracting the metal from it
- In many cases the ore is an oxide of the metal (e.g. the main aluminium ore is bauxite, which is aluminium oxide)
- A metal can be extracted from its ore chemically - by reduction with carbon or by electrolysis
- This depends on the metal's place in the reactivity series
- Metals above carbon in the reactivity series are extracted using electrolysis
- Electrolysis can also be used to purify the extracted metal
- Some ores may have to be concentrated before the metal is extracted - this just involves getting rid of the unwanted rocky material
- This process is a lot more expensive than reduction with carbon because it uses a lot of energy
- Electrolysis involves passing an electric current through a molten metal compound, splitting it into its metal and non-metal elements
- Electrons are pulled off metal atoms at the anode, causing them to go into the solution as metal ions
- Metal ions are attracted to the cathode, where they gain ellectrons and turn into metal atoms
- Electrons are pulled off metal atoms at the anode, causing them to go into the solution as metal ions
- Electrolysis can also be used to purify the extracted metal
- Metals below carbon in the reactivity series are extracted by reduction with carbon
- The metal oxide is reduced by heating it in a furnace with carbon
- The carbon reacts with the metal oxide and displaces the metal, leaving carbon dioxide and the metal by itself
- When are ore is reduced, oxygen is removed from it
- The metal oxide is reduced by heating it in a furnace with carbon
- Metals above carbon in the reactivity series are extracted using electrolysis
- This depends on the metal's place in the reactivity series
- Some ores may have to be concentrated before the metal is extracted - this just involves getting rid of the unwanted rocky material
- A metal ore is a rock which contains enough metal to make it worthwhile extracting the metal from it
- The economics of metal extraction can change over time
- If the market price of a metal drops a lot, it might not be worth extracting it
- If the price increases a lot then it might become worth extracting more of it
- As technology improves, it becomes possible to extract more metal from a sample of rock than was originally possible
- This means it might now be worth extracting metal that wasn't worth extracting in the past
- If the market price of a metal drops a lot, it might not be worth extracting it
- A metal ore is a rock which contains enough metal to make it worthwhile extracting the metal from it
- Copper extraction
- A displacement reaction can be used to extract copper
- More reactive metals react more vigorously than less reactive metals
- If you put a reactive metal into the solution of a dissolved metal compound, the reactive metal will replace the less reactive metal
- This is because the more reactive metal bonds more strongly to the non-metal bit of the compound and pushes out the less reactive metal
- If you put a reactive metal into the solution of a dissolved metal compound, the reactive metal will replace the less reactive metal
- For example, scrap iron can be used to displace copper from solution
- This is really useful because iron is cheap but copper is expensive
- If some iron is put in a solution of copper sulphate, the more reactive iron will 'kick out' the less reactive copper from the solution
- You end up with iron sulphate solution copper metal
- More reactive metals react more vigorously than less reactive metals
- The supply of copper-rich ores is limited, so it's important to recycle as much copper as posible
- The demand for copper is growing and this may lead to shortages in the future
- Scientists are looking into new ways of extracting copper from low-grade ores (ores that only contain small amounts of copper) or from the waste that is currently produced when copper is extracted
- Bioleaching uses bacteria to separate copper from copper sulphide
- The bacteria gets energy from the bond between copper and sulphur, separating out the copper from the ore in the process
- The leachate (the solution produced by the process) contains copper, which can be extracted, e.g. by filtering
- The bacteria gets energy from the bond between copper and sulphur, separating out the copper from the ore in the process
- Phytomining involves growing plants in soil that contains copper
- The plants can't use or get rid of the copper so it gradually builds up in the leaves
- The plants can be harvested, dried and burned in a furnace
- The copper can be collected from the ash left in the furnace
- The plants can be harvested, dried and burned in a furnace
- The plants can't use or get rid of the copper so it gradually builds up in the leaves
- These new methods of extraction have a much smaller impact on the environment than traditional methods of copper mining, but the disadvantage is that they're slow
- Bioleaching uses bacteria to separate copper from copper sulphide
- A displacement reaction can be used to extract copper
- Impacts of extracting metals
- Metal extraction can be bad for the environment
- People have to balance the social, economic and environmental effects of mining the ores
- Most of the issues are exactly the same as those to do with quarrying limestone
- So mining metal ores is good because it means that useful products can be made
- It also provides local people with jobs and brings money into the area, meaning services such as transport and health can be improved
- Mining ores is bad for the environment as it causes noise, scarring of the landscape and loss of habitats
- Deep mine shafts can also be dangerous for a long time after the mine has been abandoned
- So mining metal ores is good because it means that useful products can be made
- Most of the issues are exactly the same as those to do with quarrying limestone
- People have to balance the social, economic and environmental effects of mining the ores
- Reycling metals is important
- Mining and extracting metals takes lots of energy, most of which comes from burning fossil fuels
- Fossil fuels are running out so it's important to conserve them. Not only this, but burning them contributes to acid rain, global dimming and climate change
- Recycling metals only uses a small fraction of the energy needed to mine and extract new metal
- Mining and extracting metals takes lots of energy, most of which comes from burning fossil fuels
- Fossil fuels are running out so it's important to conserve them. Not only this, but burning them contributes to acid rain, global dimming and climate change
- Recycling metals only uses a small fraction of the energy needed to mine and extract new metal
- For example, recycling copper only takes 15% of the energy that's needed to mine and extract new copper
- Recycling metals only uses a small fraction of the energy needed to mine and extract new metal
- Energy doesn't come cheap, so recycling saves money too
- Fossil fuels are running out so it's important to conserve them. Not only this, but burning them contributes to acid rain, global dimming and climate change
- For example, recycling copper only takes 15% of the energy that's needed to mine and extract new copper
- Mining and extracting metals takes lots of energy, most of which comes from burning fossil fuels
- Recycling metals only uses a small fraction of the energy needed to mine and extract new metal
- Energy doesn't come cheap, so recycling saves money too
- Fossil fuels are running out so it's important to conserve them. Not only this, but burning them contributes to acid rain, global dimming and climate change
- There's a finite amount of each metal in the Earth, and recycling conserves these resources
- Recycling metal cuts down on the amount of rubbish that gets sent to landfill
- Landfill takes up space and pollutes the surroundings
- Mining and extracting metals takes lots of energy, most of which comes from burning fossil fuels
- Metal extraction can be bad for the environment
- Properties of metals
- All metals have some fairly similar basic properties
- Metals are strong but they can be bent or hammered into different shapes (malleable)
- They're great at conducting heat
- They conduct electricity well
- Metals (and especially transition metals) have loads of everyday uses because of their properties
- Their strength and malleability makes them handy for making into things like bridges and car bodies
- Their conductivity makes them great for making things like electrical wires and saucepan bases
- Metals are very useful structural materials, but some corrode when exposed to air and water, so they need to be protected, e.g. by painting
- If metals corrode, they lose their strength and hardness
- Metals can get 'tired' when stresses and strains are repeatedly put on them over time
- This is known as metal fatigue and leads to metals breaking, which can be very dangerous, e.g. in planes
- Copper is a good conductor of electricity, so it's ideal for drawing out into electrical wires
- It's hard and strong but can be bent, and it doesn't react with water
- Aluminium is corrosion-resistant and has a low density
- Pure aluminium isn't particularly strong, but it forms hard, strong alloys
- Titanium is a low density metal, which is very strong and corrosion-resistant
- All metals have some fairly similar basic properties
- Alloys
- See
- Extracting metals
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