3 Metals And Their Uses Flashcards
(88 cards)
1
Q
What two things are considered when working out whether or not to extract a metal? 2
A
- how easy it is to extract it from its ore
- how much metal the ore contains
2
Q
Give examples of metals that are found combined with oxygen?4
A
Copper
Lead
Zinc
Iron
3
Q
When a more reactive metal is combined with a less reactive metal what will it do to it?
A
Displace it
4
Q
How are gold and silver found?
A
As the elements themselves (
5
Q
If a metal is combined with oxygen what has to be done before you can use it?
A
It has to be chemically separated before it can be used
6
Q
If there is enough in a rock to make it economic to extract it what do we call the rock?
A
A metal ore
7
Q
Why is gold found as a metal rather than combined with elements in compounds?
A
They are so unreactive
8
Q
What is meant by reduction?
A
The removal of oxygen from a compound
9
Q
How are metals more reactive than carbon extracted?
A
By electrolysis
10
Q
Why is platinum being so unreactive useful with rings?
A
Being so unreactive means that the ring will last longer as it will be unaffected by external factors
11
Q
How is iron ore reduced?
A
By using carbon in a blast furnace
12
Q
Why is iron from a blast furnace not very useful?
A
Pre iron is too soft for it to be very useful
13
Q
What is an allow?
A
A metal that is mixed with other elements
14
Q
What is steel an alloy of?
A
Iron
15
Q
What are the three main types of steel and their main property?6
A
- low carbon steels which are easily shaped
- high carbon steels which are very hard
- stainless steels which are resistant to corrosion
16
Q
How is iron changed to make it useful?
A
Carefully controlled quantities of carbon and other elements are added to iron to make alloys of steel with different properties
17
Q
What is cast iron?
A
When iron from the blast furnace, poured into moulds and left to solidify is called cast iron
18
Q
How does cast iron differ from pure iron?4
A
- cast iron contains impurities
- making it harder and less reactive than pure iron
- pure iron combined oxygen will rust wheras cast iron won’t
19
Q
Why do surgical instruments made from steel contain chromium and nickel?3
A
To make it harder and stronger as well as lasting longer
20
Q
Why are aluminium and titanium do useful?
A
They are resistant to corrosion
21
Q
Where do metals come from?
A
- metals are found in the earths crust
22
Q
What are stainless steels?
A
Chromium-Nickel steels
23
Q
What are some common uses of aluminium? 6
A
- drink cans
- cooking foil
- saucepans
- aeroplanes
- high voltage cables
- bicycles
24
Q
Name six characteristics of aluminium?
A
- light
- relatively low density
- excellent conductor of energy and electricity
- malleable
- doesn’t corrode easily
- relatively reactive
25
How is aluminium extracted?4
By electrolysis
| An electric current is passed through molten aluminium oxide at high temperatures to break it down
26
Why do we use titanium for parts of jet engines?
Because it keeps its strength even at high temperatures
27
Why is titanium used in nuclear reactors? 3
It can stand up to high temperatures and it's tough oxide layer means that it's resistant to corrosion
28
Why is titanium used for replacement hip joints l?3
Low density (light)
Strength
Resistance to corrosion
29
properties of titanium?4
Light
Strong
Resistant to corrosion
High melting point
30
Why is it expensive to extract aluminium and titanium?2
Large amounts of energy is needed and there are lots of stages
31
What methods can be used to obtain copper from low grade ores?2
- bacteria are used in bioleachond
| - plants in phytomining
32
How is copper purified?
Electrolysis
33
Why are metals always deposited at the negative electrode?
Because they are always positively charged
34
What electrode are metals always deposited at?
Negative electrode
35
What is smelting?
When copper is extracted from its ore by heating
36
What chemical do we use to treat copper ore in order to form copper sulfate?
Sulfuric acid
37
Why is gold made into an allow in jewellery?
To make it last longer and harder
38
Why would copper be useful to a plumber?
- it carries water
| - it conducts electricity
39
Name three properties of the transition metals?
- strong
- but can be bent or hammered into useful shapes
- good conductors of electricity and energy
40
When pure copper is alloyed with tin what does it make?
Bronze
41
When pure copper is alloyed with zinc what does it make?
Brass
42
How can plants help to exploit low grade metal ores?
The metals can be recovered by processing the ash and burning the plants
43
Why should we recycle metals?3
Because it saves energy
And out limited metal ores and fossil fuels
The pollution from extracting metals is also reduce d
44
What is the problem with smelting for copper?
It is impure, it needs to be by electrolysis
45
Describe phytomining?
This involves growing plans in soil that contains copper
The copper absorbs in the leaves
The plants can be burned in a furnace
The copper can be collected from the ash left in the furnace
46
Why is titanium more e pensive than iron?
Many stages needed to extract titanium
| More energy and materials are needed to extract titanium
47
Why is copper extracted from ores containing a low percentage of copper compounds?
```
Copper is running out
There are no amounts of high grade copper ores left
Copper is expensive
It is now economical to extract from
Low grade ores
```
48
Why is the extraction of pure copper expensive?
Large amounts of fuels used
Extraction had many steps
Large amounts of material have to be mined
49
In electrolysis what electrode do the copper ions move towards?
Negative electrode
| Because copper joke are positively charged
50
What is used in phytomining to remove copper compounds from land?
Plants
51
Name the type of reaction that releases energy from a fuel?
Exothermic
52
Why use alloys?
Hard strong
| Resistant to corrosion
53
Advantages of biodiesel?
```
Produced less carbon dioxide and no sulphur dioxide
Produced less particulates
Renewable
Less acid rain
Conserved resources
Carbon neutral
```
54
Disadvantages of biodiesel?
```
Produced more nitrogen oxides
Deforestation for land
Land could have been sued for food
Crops are unreliable
Destruction of habitats
```
55
Why would smelting not be used?
Little copper so is uneconomical
56
describe what happens to copper ions during electrolysis?
Copper ions are attracted to the negative electrode
| Where they are reduced
57
Why is argon used in extraction?
It is very unreactive
58
Why is titanium more expensive than iron?
More stages in its manufacture
Larger amounts of energy needed
Argon had to be produced as titanium is reactive
59
Why extract iron instead of aluminium?
```
Iron used less energy for extraction
More used
More demand
Stronger
Cheaper
```
60
Suggest two reasons why aluminium drink cans should be recycled?
```
Saved resources
Landi
Saves energy
Less carbon dioxide
Less quarrying
```
61
What type of metals are extracted by electrolysis?
Metals that are more reactive than carbon have to be extracted by electrolysis
62
Properties and uses of stainless steel?
Resistant to corrosion
Cutlery
Containers for corrosive substances
63
Properties and uses of high carbon steel?
Very hard and inflexible
Blades for cutting tools
Bridges
64
Properties and uses of low carbon steel?
Easily shaped
| Car bodies
65
Why is pure iron softer than cast iron?
Easier for layers in pure iron to slide over eachother
| Same size atoms
66
What are most metals found as?
Compounds that require chemical reactions to extract the metal
67
How can copper be extracted from copper rich ores?
Smelting
| Then purified by electrolysis
68
How can copper be obtained from solutions of copper salts?
Electrolysis
Or
Displacement using scrap iron
69
Describe phytomining?
Plants absorb dissolved metal ions in the soul through their roots
Plants burned metals extracted from ash
Then eg Copper ions can be leached (dissolved) from the ash by adding sulphuric acid
Making a solution of copper sulphate
Electrolysis can purify this
70
Why should we recycle metal?
Extracting them used limited resources and is expensive in terms of energy
Also effects the environment
71
What makes iron brittle?
It contains impurities
72
What are steels?
Mixtures of iron with carbon
73
Properities of copper?
Good conductor
Can be bent but is hard enough to be used to make pipes or tanks
Does not react with water
74
What is copper useful for?
Electrical wiring
| Plumbing
75
Why are both titanium and aluminium useful metals?
Low density
| Resistant to corrosion
76
What is cast iron used to make?
Wood burning stoves
| Engines
77
Why is titanium used for aircrafts and racing bikes?
Strength
| Low density
78
Why is titanium used for jet engines and nuclear reactors?
Can withstand high temperatures
| Resistant to corrosion
79
How is bronze made?
Mixing copper with ton
80
How is brass made?
Mixing copper with zinc
81
Copper properties?
Tough
Resistant to corrosion
Used in ship propellers
82
Properties of brass?
Very hard but worked le
Can be hammered into sheets and intricate shaped
Used to make musical instruments
83
What is copper used for?
Pipes that carry water (dosent react with water)
| Wired that contact electricity
84
Why recycle metal?
Reduces the need to mine the metal ore
Conserved resources
Saves energy
85
Used of steel?
Bridges
Skyscrapers
Concrete bridges (reinforced with steel rods)
86
Describe bio leaching?
Bacteria grow on the ore
Produce a solution as a byproduct of this
Solution can then be purified using electrolysis or displacement using scrap iron
87
How do you extract copper from its ore?
Smelting
| React with sulphuric acid
88
Extracting using carbon is an example of what type of reaction?
Reduction
