C5.3 - Extracting metals Flashcards
How long have metals been important to people?
Metals have been important to people for thousands of years
Metals have been important to people for thousands of years.
How can you follow the course of history?
You can follow the course of history by the materials people used
Metals have been important to people for thousands of years.
You can follow the course of history by the materials people used.
What came after the Stone Age?
After the Stone Age came the Bronze Age (copper/tin)
Where are metals found?
Metals are found in the Earth’s crust
Metals are found in the Earth’s crust.
What are most metals?
Most metals are combined chemically with other chemical elements
Metals are found in the Earth’s crust.
Most metals are combined chemically with other chemical elements, often with oxygen or sulfur.
What does this mean?
This means that the metal must be chemically separated from its compounds before it can be used
Ore
An ore is a rock which contains enough metal to make it economically worthwhile to extract the metal
How do you get ores?
Ores are mined from the ground
Ores are mined from the ground.
What do some need to be before the metal is extracted and purified?
Some ores need to be concentrated before the metal is:
- Extracted
- Purified
Ores are mined from the ground.
Some ores need to be concentrated before the metal is extracted and purified.
Example
For example, copper ores are ground up into a powder
The Angel of the North stands how many m tall?
The Angel of the North stands 20 m tall
The Angel of the North stands 20 m tall.
What is it made of?
The Angel of the North is made of steel
What does whether it is worth extracting a particular metal depend on?
Whether it is worth extracting a particular metal depends on:
- How easy it is to extract it from its ore
- How much metal the ore contains
- The changing demands for a particular metal
Whether it is worth extracting a particular metal depends on how easy it is to extract it from its ore, how much metal the ore contains and the changing demands for a particular metal.
What can these 3 factors do?
These 3 factors can change over time
Whether it is worth extracting a particular metal depends on how easy it is to extract it from its ore, how much metal the ore contains and the changing demands for a particular metal.
These 3 factors can change over time.
Examples
For example:
- A new, cheaper method might be discovered for extracting a metal
- You might also discover a new way to extract a metal efficiently from rock which contains only small amounts of a metal ore
Whether it is worth extracting a particular metal depends on how easy it is to extract it from its ore, how much metal the ore contains and the changing demands for a particular metal.
These 3 factors can change over time.
For example, a new, cheaper method might be discovered for extracting a metal and you might also discover a new way to extract a metal efficiently from rock which contains only small amounts of a metal ore.
An ore that was once thought of as ‘low grade’ could then become what?
An ore that was once thought of as ‘low grade’ could then become an economic source of a metal
A few metals, such as gold and silver, are so unreactive that they are what?
A few metals, such as:
1. Gold
2. Silver
,are so unreactive that they are found in the Earth as the metals (elements) themselves
A few metals, such as gold and silver, are so unreactive that they are found in the Earth as the metals (elements) themselves.
How do they exist?
A few metals, such as:
1. Gold
2. Silver
,exist in their native state
Sometimes, what is a nugget of gold?
Sometimes a nugget of gold is so large it can simply be picked up
Sometimes a nugget of gold is so large it can simply be picked up.
What happens at other times?
At other times, tiny flakes have to be physically separated from:
1. Sand
2. Rocks
by panning
The reactivity series
The reactivity series is:
- Potassium
- Sodium
- Calcium
- Magnesium
- Aluminium
- (Carbon)
- Zinc
- Iron
- Tin
- Lead
- (Hydrogen)
- Copper
- Silver
- Gold
- Platinum
What does the way that a metal is extracted depend on?
The way that a metal is extracted depends on its place in the reactivity series
The way that a metal is extracted depends on its place in the reactivity series.
The reactivity series lists the metals in order of their what?
The reactivity series lists the metals in order of their reactivity
What will a more reactive metal do?
A more reactive metal will displace a less reactive metal from its compounds
A more reactive metal will displace a less reactive metal from its compounds.
What will carbon (a non-metal) also do?
Carbon (a non-metal) will also displace less reactive metals from their oxides
A more reactive metal will displace a less reactive metal from its compounds.
Carbon (a non-metal) will also displace less reactive metals from their oxides.
What is carbon used to do?
Carbon is used to extract some metals from their ores in industry
How can you find many metals, such as copper, lead, iron and zinc?
You can find many metals, such as: 1. Copper 2. Lead 3. Iron 4. Zinc combined with oxygen as metal oxides
You can find many metals, such as copper, lead, iron and zinc combined with oxygen as metal oxides.
Why is carbon used to extract the metals from their oxides?
Carbon is used to extract the metals from their oxides, because carbon:
- Is more reactive than each of these metals
- Will displace less reactive metals from their oxides
What must you do to extract metals from their oxides using carbon?
To extract metals from their oxides using carbon, you must heat the metal oxide with carbon
To extract metals from their oxides using carbon, you must heat the metal oxide with carbon.
The carbon removes the oxygen from the metal oxide to form carbon dioxide.
The metal is also formed, as the element.
The word equation for this
The word equation for using carbon to extract metals from their oxides is:
Metal oxide + Carbon —> Metal oxide + Carbon dioxide
To extract metals from their oxides using carbon, you must heat the metal oxide with carbon.
Example
For example:
heat
Lead oxide + Carbon —> Lead + Carbon dioxide
The removal of oxygen from a compound is called what?
The removal of oxygen from a compound is called chemical reduction
The non-metal used as the reducing agent for when the metal tungsten is to be extracted from its oxide
The non-metal used as the reducing agent for when the metal tungsten is to be extracted from its oxide is hydrogen
Why is the non-metal used as the reducing agent for when the metal tungsten is to be extracted from its oxide hydrogen, even though carbon would be cheaper?
The non-metal used as the reducing agent for when the metal tungsten is to be extracted from its oxide is hydrogen, even though carbon would be cheaper, because the carbon forms a compound, tungsten carbide, with the metal formed by reduction
The non-metal used as the reducing agent for when the metal tungsten is to be extracted from its oxide is hydrogen, even though carbon would be cheaper, because the carbon forms a compound, tungsten carbide, with the metal formed by reduction.
What is the tungsten obtained from reduction of its oxide by hydrogen?
The tungsten obtained from reduction of its oxide by hydrogen is very pure
How are the metals more reactive than carbon extracted from their ores?
The metals more reactive than carbon are extracted from their ores by electrolysis of the molten metal compound
Electrolysis
Electrolysis is the breakdown of a substance containing ions by electricity
Metals have been important to people for thousands of years.
You can follow the course of history by the materials people used.
After the Stone Age came the Bronze Age (copper/tin) and then what?
After the Stone Age came the:
- Bronze Age (copper/tin)
- Then the Iron Age
Most metals are combined chemically with other chemical elements, often with what?
Most metals are combined chemically with other chemical elements, often with:
1. Oxygen
Or,
2. Sulfur
Ores are mined from the ground.
Some ores need to be concentrated before the metal is extracted and purified.
For example, copper ores are ground up into a powder.
Then they are what?
Then they are mixed with:
- Water
- A chemical that makes the copper compound repel water
Ores are mined from the ground.
Some ores need to be concentrated before the metal is extracted and purified.
For example, copper ores are ground up into a powder.
Then they are mixed with water and a chemical that makes the copper compound repel water.
Air is then what?
Air is then bubbled through the mixture
Ores are mined from the ground.
Some ores need to be concentrated before the metal is extracted and purified.
For example, copper ores are ground up into a powder.
Then they are mixed with water and a chemical that makes the copper compound repel water.
Air is then bubbled through the mixture and the copper compound does what?
- Air is then bubbled through the mixture
2. The copper compound floats on top as a froth
Ores are mined from the ground.
Some ores need to be concentrated before the metal is extracted and purified.
For example, copper ores are ground up into a powder.
Then they are mixed with water and a chemical that makes the copper compound repel water.
Air is then bubbled through the mixture and the copper compound floats on top as a froth.
The rocky bits do what?
The rocky bits sink
Ores are mined from the ground.
Some ores need to be concentrated before the metal is extracted and purified.
For example, copper ores are ground up into a powder.
Then they are mixed with water and a chemical that makes the copper compound repel water.
Air is then bubbled through the mixture and the copper compound floats on top as a froth.
The rocky bits sink and what is scraped off the top?
The:
- Rocky bits sink
- Concentrated copper compound is scraped off the top
Ores are mined from the ground.
Some ores need to be concentrated before the metal is extracted and purified.
For example, copper ores are ground up into a powder.
Then they are mixed with water and a chemical that makes the copper compound repel water.
Air is then bubbled through the mixture and the copper compound floats on top as a froth.
The rocky bits sink and the concentrated copper compound is scraped off the top.
It is then ready to what?
It is then ready to have its copper extracted.
The Angel of the North is made of steel, which contains what?
The Angel of the North is made of steel, which contains a small amount of copper
The reactivity series lists the metals in order of their reactivity, which includes the non-metals what?
The reactivity series lists the metals in order of their reactivity, which includes the non-metals:
- Carbon
- Hydrogen
To extract metals from their oxides using carbon, you must heat the metal oxide with carbon.
The carbon does what to form carbon dioxide?
The carbon removes the oxygen from the metal oxide to form carbon dioxide
To extract metals from their oxides using carbon, you must heat the metal oxide with carbon.
The carbon removes the oxygen from the metal oxide to form carbon dioxide.
What is also formed, as the element?
The metal is also formed, as the element
The non-metal used as the reducing agent for when the metal tungsten is to be extracted from its oxide is hydrogen, even though what would be cheaper?
The non-metal used as the reducing agent for when the metal tungsten is to be extracted from its oxide is hydrogen, even though carbon would be cheaper
The non-metal used as the reducing agent for when the metal tungsten is to be extracted from its oxide is hydrogen, even though carbon would be cheaper, because the carbon forms a compound, tungsten carbide, with the metal formed by reduction.
The tungsten obtained from reduction of its oxide by hydrogen is very pure.
The chemical equation
The chemical equation is:
heat
Tungsten oxide + Hydrogen —> Tungsten + Water (as steam)
