Sources Of Metals, Extracting metals, Using Metals And Alloys

Question 1

What is a metal ore?

Answer 1

A metal ore is a rock that contains enough of the metal to make it worthwhile extracting.

Question 2

What are some examples of ways we can extract metals from their ores?

Answer 2

Some examples are through processes such as electrolysis, using a blast furnace or by reacting with more reactive material.

Question 3

In many cases, the ore is an…

Answer 3

In many cases the ore is an oxide of the metal.

Question 4

The extraction of these metals from their ores is usually what type of process and why?

Answer 4

The extraction of these metals is a reduction process since oxygen is being removed (when the ore is an oxide of the metal).

Question 5

What is the name for an iron ore?

Answer 5

haematite

Question 6

What is the name for an aluminium ore?

Answer 6

bauxite

Question 7

Do unreactive metals have to be extracted chemically and explain why?

Answer 7

Unreactive metals do not have to be extracted chemically as they are often found as the uncombined element. This occurs as they do not easily react with other substances due to their chemical stability

Question 8

What are some examples of unreactive metals?

Answer 8

Examples include gold and platinum which can both be mined directly from the Earth’s crust.

Question 9

Where are the most reactive metals (on the reactivity series)?

Answer 9

The most reactive metals are at the top of the series.

Question 10

What determines how reactive a metal is and it’s position on the reactivity series?

Answer 10

The tendency to become oxidised is linked to how reactive a metal is and therefore its position on the reactivity series
Metals higher up are therefore less resistant to oxidation than the metals placed lower down which are more resistant to oxidation

Question 11

How can we determine a metal’s method of extraction and explain?

Answer 11

The position of the metal on the reactivity series determines the method of extraction
Higher placed metals (above carbon) have to be extracted using electrolysis as they are too reactive and cannot be reduced by carbon
Lower placed metals can be extracted by heating with carbon which reduces them

Question 12

Why can’t we extract higher-placed metals (above carbon) by carbon?

Answer 12

Higher placed metals (above carbon) are too reactive and therefore cannot be reduced by carbon

Question 13

What happens to lower-placed metals when we extract them?

Answer 13

Lower placed metals can be extracted by heating with carbon which thus reduces them

Question 14

Which metals are extracted by electrolysis of the molten chloride or molten oxide?

Answer 14

Potassium
Sodium
Lithium
Calcium
Magnesium
Aluminium

Question 15

Briefly describe electrolysis

Answer 15

Large amounts of the electricity is required and it is an expensive process.

Question 16

How are Potassium, Sodium, Lithium, Calcium, Magnesium and Aluminium extracted from their ores?

Answer 16

Extracted by electrolysis of the molten chloride or molten oxide

Question 17

Which metals are extracted by heating with a reducing agent such as carbon or carbon monoxide in a blast furnace?

Answer 17

Zinc
Iron
Hydrogen
Copper

Question 18

Briefly describe extraction by heating with a reducing agent (like carbon or carbon monoxide) in a blast furnace.

Answer 18

Cheap process as carbon is cheap and can be source of heat as well

Question 19

How are Zinc, Iron and Copper extracted from their ores?

Answer 19

Extracted by heating with a reducing agent such as carbon or carbon monoxide in a blastfurnance

Question 20

How are silver and gold extracted from their ores?

Answer 20

They are not extracted from ores, as they are unreactive and found as pure elements.

Question 21

Uses of Aluminium

Answer 21

Aeroplane bodies
Overhead power cables
Saucepans
Food cans
Window frames

Question 22

Property of aluminium in aeroplane bodies

Answer 22

High strength-to-weight ratio (low density)

Question 23

Property of aluminium in overhead power cables

Answer 23

Good conductor ofelectricity

Question 24

Property of aluminium in saucepans

Answer 24

Good conductor of heat

Question 25

Property of aluminium in food cans

Answer 25

Non-toxic, resistant to corrosion and acidic food stuffs, malleable

Question 26

Property of aluminium in window frames

Answer 26

Resistant to corrosion

Question 27

Uses of copper

Answer 27

Electrical wires and water pipes

Question 28

Property of copper in electrical wires

Answer 28

Good conductor of electricity and malleable

Question 29

Property of copper in water pipes

Answer 29

Easy to work with and bend, non- toxic and unreactive (does not react with water)

Question 30

What are the types of steel?

Answer 30

Mild steel, high carbon steel, low alloy steel and stainless steel

Question 31

Describe mild steel (iron alloyed with…, the use and most important property)

Answer 31

Iron alloyed with 0.25% carbon
Use = Car body panels, wires
Most important property = Soft and malleable

Question 32

Describe high carbon steel (iron alloyed with…, the use and most important property)

Answer 32

Iron alloyed with 0.5-1.4% carbon
Use = Tools and chisels
Most important property = Hard

Question 33

Describe low alloy steel (iron alloyed with…, the use and most important property)

Answer 33

Iron alloyed with = 1-5% of other Metals (Chromium, Nickel, Titanium)
Use = Construction, bridges, high speed tools
Most important property = Hard and strong, low ductility and malleability

Question 34

Describe stainless steel (iron alloyed with…, the use and most important property)

Answer 34

Iron alloyed with = 20% Chromium and 10% Nickel
Use = Cutlery and sinks, chemical plants
Most important property = Strong and resistant to corrosion

Question 35

What are alloys?

Answer 35

Alloys are mixtures of metals, where the metals are mixed together physically but are not chemically combined
They can also be made from metals mixed with nonmetals such as carbon

Question 36

Describe the properties of alloys in comparison to the metals they contain and explain why

Answer 36

Alloys often have properties that can be very different to the metals they contain, for example they can have greater strength, hardness or resistance to corrosion or extreme temperatures. This is due to the fact that alloys contain atoms of different sizes, which distorts the regular arrangements of atoms
This makes it more difficult for the layers to slide over each other, so they are usually much harder than the pure metal.

Question 37

Why are alloys usually much harder than the pure metal?

Answer 37

Alloys contain atoms of different sizes, which distorts the regular arrangements of atoms
This makes it more difficult for the layers to slide over each other, so they are usually much harder than the pure metal