C1.4 Obtaining and using metals

Question 1

Where are metals extracted from?

Answer 1

Ores in the Earth’s crust

Question 2

How are most metals extracted from their ores?

Answer 2

• heating with carbon

- electrolysis

Question 3

What are ores?

Answer 3

Rocks that contain enough of a metal for extraction to create profit

Question 4

What is extraction?

Answer 4

The process of obtaining a metal from an ore by using chemical reactions

Question 5

What happens to the cost of extraction as the reactivity of a metal increases?

Answer 5

It increases

Question 6

Why does it cost more to extract metals with a high reactivity?

Answer 6

Electrolysis costs more than heating with carbon because of the cost of electricity

Question 7

How are metals up to and including zinc on the reactivity series extracted?

Answer 7

By heating with carbon

Question 8

How are metals above zinc on the reactivity series extracted?

Answer 8

By electrolysis

Question 9

What is reduction in terms of electrons?

Answer 9

The gaining of electrons

Question 10

Is the extraction of metal from their oxides reduction or oxidation?

Answer 10

Reduction

Question 11

What is reduction in terms of oxygen?

Answer 11

The loss of oxygen

Question 12

What is oxidation in terms of electrons?

Answer 12

The loss of electrons

Question 13

What is oxidation in terms of oxygen?

Answer 13

The gaining of oxygen

Question 14

What is rusting?

Answer 14

The corrosion of iron

Question 15

What does the rusting of iron produce?

Answer 15

iron(III) oxide

Question 16

What happens to the speed of corrosion as the reactivity of a metal increases?

Answer 16

It speeds up

Question 17

Is the corrosion of a metal reduction or oxidation?

Answer 17

Oxidation

Question 18

What are the advantages of recycling metal?

Answer 18

• natural reserves of metal ores will last longer
• it takes less energy to recycle instead of extract most metal ores
• less pollution
• less waste metals are disposed of in landfill sites

Question 19

What are the disadvantages of mining?

Answer 19

It damages the landscape and creates dust and noise pollution

Question 20

What are the disadvantages of recycling metal?

Answer 20

• the costs and energy used to collect, sort and transport metals
• recycling can sometimes be more expensive than mining for some metals

Question 21

Why are recycled metals cheaper than mined ones?

Answer 21

It takes less energy to recycle a metal than to mine for it

Question 22

How are iron and steel seperated from other metals in a recycling plant?

Answer 22

By using a magnet

Question 23

How are metals that aren’t steel or iron sorted in a recycling plant?

Answer 23

By hand

Question 24

What are the properties of aluminium?

Answer 24

• low density

- doesn’t corrode

Question 25

What is aluminium used for?

Answer 25

To make aeroplanes and cars

Question 26

What are the benefits of using aluminium for aeroplanes and cars?

Answer 26

It makes them lighter which means less fuel is needed

Question 27

What are the properties of all metals?

Answer 27

- shiny when polished - conduct heat and electricity - malleable - ductile

Question 28

What are the properties of copper?

Answer 28

- extremely good conductor | - low reactivity

Question 29

What is copper used for?

Answer 29

- making copper cables | - making water pipes

Question 30

What are the properties of gold?

Answer 30

- very unreactive - doesn't corrode - remains shiny - one of the best electrical conductors

Question 31

What are the uses of gold?

Answer 31

- jewellery | - in electronic devices

Question 32

What are the properties of steel?

Answer 32

- strong | - magnetic

Question 33

What are the uses of steel?

Answer 33

- electrical goods - machinery - cars - frames for buildings - bridges

Question 34

What is an alloy?

Answer 34

A mixture of metals

Question 35

Why is an alloy stronger than a pure metal?

Answer 35

It has atoms of different sizes so they can't slide past each other as easily

Question 36

Why is iron alloyed with other metals?

Answer 36

- to get stronger | - to sometimes resist corrosion

Question 37

What is stainless steel made up of?

Answer 37

Iron and small amounts of chromium and nickel

Question 38

What is the purity of gold measured in?

Answer 38

Carats or fineness

Question 39

How many carats does pure gold have?

Answer 39

24

Question 40

What is the fineness of pure gold?

Answer 40

1000 parts per 1000

Question 41

What is nitinol?

Answer 41

An alloy of nickel and titanium

Question 42

What is a shape memory alloy?

Answer 42

An alloy that returns to it's original shape when heated

Question 43

What are some uses of shape memory alloys?

Answer 43

- as stents in damaged blood vessels | - to make flexible spectacle frames

Question 44

What is a smart material?

Answer 44

A material with a property that changes when there is a change in conditions

Question 45

Why is gold alloyed with other metals?

Answer 45

To make it harder and stronger