C14.4 - Extracting metals from ores

Question 1

Where is most copper extracted from?

Answer 1

Most copper is extracted from copper-rich ores

Question 2

Most copper is extracted from copper-rich ores.

What are copper-rich ores?

Answer 2

Copper-rich ores are a finite resource and are in danger of running out

Question 3

Most copper is extracted from copper-rich ores.

What are there used to obtain the copper metal from the ore?

Answer 3

There are 2 main methods used to obtain the copper metal from the ore

Question 4

There are 2 main methods used to obtain the copper metal from the ore.
What happens in 1 method?

Answer 4

There are 2 main methods used to obtain the copper metal from the ore
In 1 method:
Sulfuric acid is used to produce copper sulfate solution, before extracting the copper metal

Question 5

There are 2 main methods used to obtain the copper metal from the ore.
In 1 method:
Sulfuric acid is used to produce copper sulfate solution, before extracting the copper metal.
What is the other process called?

Answer 5

There are 2 main methods used to obtain the copper metal from the ore:
Sulfuric acid is involved in the 1st method
The other process is called smelting (roasting):
Copper ore is heated to a high temperature in a furnace with air, to produce impure copper

Question 6

In smelting (roasting):
Copper ore is heated to a high temperature in a furnace with air, to produce impure copper.
Where do we use the impure copper?

Answer 6

We use the impure copper as the positive electrode in electrolysis cells to make pure copper

Question 7

How much copper is still produced by smelting?

Answer 7

About 80% of copper is still produced by smelting

Question 8

What does smelting and purifying copper ore use?

Answer 8

Smelting and purifying copper ore uses huge amounts of energy and electricity

Question 9

Smelting and purifying copper ore uses huge amounts of energy and electricity.
What does this cost?

Answer 9

Smelting and purifying copper ore uses huge amounts of energy and electricity
This costs a lot of money and will cause pollution of the environment

Question 10

What can mining copper ores leave?

Answer 10

Mining copper ores can leave huge scars on the landscape

Question 11

Mining copper ores can leave huge scars on the landscape.

What is this quarrying of ores called?

Answer 11

Mining copper ores can leave huge scars on the landscape

This quarrying of ores is called open-cast mining

Question 12

Mining copper ores can leave huge scars on the landscape.
This quarrying of ores is called open-cast mining.
How much copper comes from open-cast mines?

Answer 12

Mining copper ores can leave huge scars on the landscape
This quarrying of ores is called open-cast mining
About 90% of copper comes from open-cast mines

Question 13

Mining copper ores can leave huge scars on the landscape.
This quarrying of ores is called open-cast mining.
About 90% of copper comes from open-cast mines.
What are our supplies of copper-rich ores?

Answer 13

Mining copper ores can leave huge scars on the landscape
This quarrying of ores is called open-cast mining
About 90% of copper comes from open-cast mines
Our supplies of copper-rich ores are a limited, finite resource

Question 14

What are metal ions always?

Answer 14

Metal ions are always positively charged

Question 15

Metal ions are always positively charged.

Therefore, in electrolysis what are they attracted to?

Answer 15

Metal ions are always positively charged

Therefore, in electrolysis they are attracted to and deposited at the negative electrode

Question 16

Metal ions are always positively charged.
Therefore, in electrolysis they are attracted to and deposited at the negative electrode.
In industry, what is carried out in many cells running at once?

Answer 16

Metal ions are always positively charged
Therefore, in electrolysis they are attracted to and deposited at the negative electrode
In industry, the electrolysis of copper is carried out in many cells running at once

Question 17

Metal ions are always positively charged.
Therefore, in electrolysis they are attracted to and deposited at the negative electrode.
In industry, the electrolysis of copper is carried out in many cells running at once.
What does this method give?

Answer 17

Metal ions are always positively charged
Therefore, in electrolysis they are attracted to and deposited at the negative electrode
In industry, the electrolysis of copper is carried out in many cells running at once
This method gives the very pure copper needed to make electrical wiring

Question 18

In industry, the electrolysis of copper is carried out in many cells running at once.
This method gives the very pure copper needed to make electrical wiring.
Why is electrolysis also used?

Answer 18

In industry, the electrolysis of copper is carried out in many cells running at once
This method gives the very pure copper needed to make electrical wiring
Electrolysis is also used to purify the impure copper extracted by smelting

Question 19

In industry, the electrolysis of copper is carried out in many cells running at once.
Describe the anode

Answer 19

In industry, the electrolysis of copper is carried out in many cells running at once
The impure copper anode gets smaller

Question 20

In industry, the electrolysis of copper is carried out in many cells running at once.
The impure copper anode gets smaller.
Describe the solution

Answer 20

In industry, the electrolysis of copper is carried out in many cells running at once
The impure copper anode gets smaller
The solution contains copper ions

Question 21

In industry, the electrolysis of copper is carried out in many cells running at once.
The impure copper anode gets smaller.
The solution contains copper ions.
Describe the left of the bottom of the cell

Answer 21

In industry, the electrolysis of copper is carried out in many cells running at once
The impure copper anode gets smaller
The solution contains copper ions
To the left of the bottom of the cell, there is sludge containing precious metals

Question 22

In industry, the electrolysis of copper is carried out in many cells running at once.
The impure copper anode gets smaller.
The solution contains copper ions.
To the left of the bottom of the cell, there is sludge containing precious metals.
Describe the cathode

Answer 22

In industry, the electrolysis of copper is carried out in many cells running at once
The impure copper anode gets smaller
The solution contains copper ions
To the left of the bottom of the cell, there is sludge containing precious metals
The cathode is very pure copper

Question 23

In industry, the electrolysis of copper is carried out in many cells running at once.
The impure copper anode gets smaller.
The solution contains copper ions.
To the left of the bottom of the cell, there is sludge containing precious metals.
The cathode is very pure copper.
How often are the cathodes removed?

Answer 23

In industry, the electrolysis of copper is carried out in many cells running at once
The impure copper anode gets smaller
The solution contains copper ions
To the left of the bottom of the cell, there is sludge containing precious metals
The cathode is very pure copper
The cathodes are removed about every 2 weeks

Question 24

What happens at the negative copper electrode (cathode)?

Answer 24

At the negative copper electrode (cathode), we get reduction - The copper ions gain 2 electrons to become atoms

Question 25

What happens at the positive copper electrode (anode)?

Answer 25

At the positive copper electrode (anode), we get oxidation

Question 26

How can copper be extracted in industry?

Answer 26

Copper can be extracted in industry from copper sulfate solution by adding scrap iron

Question 27

Copper can be extracted in industry from copper sulfate solution by adding scrap iron. Why is scrap iron added?

Answer 27

Copper can be extracted in industry from copper sulfate solution by adding scrap iron Scrap iron is added because iron can displace copper from its solutions

Question 28

Copper can be extracted in industry from copper sulfate solution by adding scrap iron. Scrap iron is added because iron can displace copper from its solutions. Iron + copper(II) sulfate --->

Answer 28

Iron + copper(II) sulfate ---> iron (II) sulfate + copper

Question 29

What are scientists developing?

Answer 29

Instead of extracting copper from our limited copper-rich ores, scientists are developing ways to get copper from low-grade ores

Question 30

Instead of extracting copper from our limited copper-rich ores, scientists are developing ways to get copper from low-grade ores. What would this be using traditional methods?

Answer 30

Instead of extracting copper from our limited copper-rich ores, scientists are developing ways to get copper from low-grade ores This would be uneconomical using traditional methods

Question 31

Instead of extracting copper from our limited copper-rich ores, scientists are developing ways to get copper from low-grade ores. This would be uneconomical using traditional methods. What do new techniques use?

Answer 31

``` New techniques use: 1. Bacteria (bioleaching) Or, 2. Plants (phytomining) to help extract copper ```

Question 32

What happens in phytomining?

Answer 32

In phytomining, plants that can absorb copper ions are grown on soil containing low-grade copper ore

Question 33

In phytomining, plants that can absorb copper ions are grown on soil containing low-grade copper ore. Where could this be?

Answer 33

In phytomining, plants that can absorb copper ions are grown on soil containing low-grade copper ore This could be on slag heaps of previously discarded waste from the processing of copper-rich ores

Question 34

In phytomining, plants that can absorb copper ions are grown on soil containing low-grade copper ore. This could be on slag heaps of previously discarded waste from the processing of copper-rich ores. Then what happens?

Answer 34

In phytomining, plants that can absorb copper ions are grown on soil containing low-grade copper ore This could be on slag heaps of previously discarded waste from the processing of copper-rich ores Then the plants are burnt and copper is extracted from copper compounds in the ash

Question 35

In phytomining, plants that can absorb copper ions are grown on soil containing low-grade copper ore. This could be on slag heaps of previously discarded waste from the processing of copper-rich ores, Then the plants are burnt and copper is extracted from copper compounds in the ash. What can happen to the copper ions?

Answer 35

In phytomining, plants that can absorb copper ions are grown on soil containing low-grade copper ore This could be on slag heaps of previously discarded waste from the processing of copper-rich ores Then the plants are burnt and copper is extracted from copper compounds in the ash The copper ions can be 'leached' (dissolved) from the ash by adding sulfuric acid

Question 36

In phytomining, plants that can absorb copper ions are grown on soil containing low-grade copper ore. This could be on slag heaps of previously discarded waste from the processing of copper-rich ores. Then the plants are burnt and copper is extracted from copper compounds in the ash. The copper ions can be 'leached' (dissolved) from the ash by adding sulfuric acid. What does this make?

Answer 36

In phytomining, plants that can absorb copper ions are grown on soil containing low-grade copper ore This could be on slag heaps of previously discarded waste from the processing of copper-rich ores Then the plants are burnt and copper is extracted from copper compounds in the ash The copper ions can be 'leached' (dissolved) from the ash by adding sulfuric acid This makes a solution (leachate) of copper sulfate

Question 37

In phytomining, plants that can absorb copper ions are grown on soil containing low-grade copper ore. This could be on slag heaps of previously discarded waste from the processing of copper-rich ores. Then the plants are burnt and copper is extracted from copper compounds in the ash. The copper ions can be 'leached' (dissolved) from the ash by adding sulfuric acid. This makes a solution (leachate) of copper sulfate. What makes pure copper metal?

Answer 37

In phytomining, plants that can absorb copper ions are grown on soil containing low-grade copper ore This could be on slag heaps of previously discarded waste from the processing of copper-rich ores Then the plants are burnt and copper is extracted from copper compounds in the ash The copper ions can be 'leached' (dissolved) from the ash by adding sulfuric acid This makes a solution (leachate) of copper sulfate Displacement by scrap iron and then electrolysis makes pure copper metal

Question 38

What happens in bioleaching?

Answer 38

In bioleaching, bacteria feed on low-grade metal ores

Question 39

In bioleaching, bacteria feed on low-grade metal ores. | How can a solution of copper ions (leachate) be obtained from waste copper ore?

Answer 39

In bioleaching, bacteria feed on low-grade metal ores By a combination of biological and chemical processes, a solution of copper ions (leachate) can be obtained from waste copper ore

Question 40

In bioleaching, bacteria feed on low-grade metal ores. By a combination of biological and chemical processes, a solution of copper ions (leachate) can be obtained from waste copper ore. What is used to extract the copper from the leachate?

Answer 40

In bioleaching, bacteria feed on low-grade metal ores By a combination of biological and chemical processes, a solution of copper ions (leachate) can be obtained from waste copper ore Scrap iron and electrolysis is used to extract the copper from the leachate

Question 41

How much copper comes from bioleaching?

Answer 41

About 20% of copper comes from bioleaching

Question 42

About 20% of copper comes from bioleaching. | What is this likely to do?

Answer 42

About 20% of copper comes from bioleaching | This is likely to increase as sources of copper-rich ores run out

Question 43

What is bioleaching?

Answer 43

Bioleaching is a slow process, so scientists are researching ways to speed it up

Question 44

Bioleaching is a slow process, so scientists are researching ways to speed it up. At present, how long can it take to extract 50% of the metal from a low-grade ore?

Answer 44

Bioleaching is a slow process, so scientists are researching ways to speed it up At present, it can take years to extract 50% of the metal from a low-grade ore