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