Metals and Their Uses

Question 1

Where are metals usually found?

Answer 1

In the Earth’s crust

Question 2

What is an ore?

Answer 2

A rock containing enough metal/metal compound to make it worth extracting the metal

Question 3

How are some metals low in the reactivity series found?

Answer 3

As pure or nearly pure metals. Little extraction is needed as they can be extracted through physical methods.

Question 4

How can metals be extracted from compounds?

Answer 4

Through displacement reactions using a more reactive element

Question 5

How are metals that are less reactive than carbon extracted from their oxides?

Answer 5

They are heated with carbon and a reduction reaction occurs as the carbon removes the oxygen (forming carbon dioxide), leaving just the metal. This method is used comercially if possible

Question 6

How is iron oxide reduced to make a purer form of iron?

Answer 6

In a blast furnace at high temperatures using carbon.

Question 7

What do many of the ores used to produce iron contain?

Answer 7

Iron (II) oxide

Question 8

What percentage of iron does the iron from a blast furnace contain?

Answer 8

96% iron - this is known as cast iron

Question 9

What are the properties of cast iron?

Answer 9

The impurities make it hard and brittle so it has few uses

Question 10

What are the properties of pure iron?

Answer 10

Soft - too soft for many uses

Question 11

What are steels?

Answer 11

Alloys of iron - mixtures of iron with carbon and other elements

Question 12

What is most iron used to make?

Answer 12

Steels

Question 13

What are the properties of low-carbon steels compared to high-carbon steels?

Answer 13

Easily shaped vs. hard

Question 14

Stainless steel contains …? This means that it…?

Answer 14

Contains larger quanities of other metals. This means that it resists corrosion.

Question 15

What do steels contain?

Answer 15

Carefully controlled quanities of carbon and other elements. This gives them specific properties for specific uses.

Question 16

What are the properties of aluminium?

Answer 16

• Low density compared to other hard metals
• Even though it’s high in the reactivity series it is resistant to corrosion
• Pure aluminium is not very strong, but its alloys are stronger and harder.

Question 17

What are the properties of titanium?

Answer 17

• Low density compared to other hard metals
• Very strong
• Resistant to corrosion

Question 18

How is aluminium extracted?

Answer 18

• More reactive than carbon so cannot be reduced.
• Has to be extracted through the electrolysis of molten aluminium oxide.
• This requires high temperatures and lots of energy, making aluminium expensive

Question 19

How is titanium extracted?

Answer 19

• Can be reduced using carbon, but reacts with it making the metal brittle.
• Instead it is extracted from its ore by a process that involves several stages and large amounts of energy.
• This makes titanium expensive

Question 20

How is most copper extracted?

Answer 20

From copper rich ores by smelting - this means heating the ore strongly in a furnace. This produces impure copepr

Question 21

How is copper purified?

Answer 21

Using electrolysis

Question 22

What are the disadvantages of extracting copper using smelting/electrolysis?

Answer 22

• It requires huge amounts of heating and electricity (lots of energy)
• Copper-rich ores are a limitted resource

Question 23

Describe the new ways scientists are developing to extract copper.

Answer 23

• These new methods work by extracting copper from low-grade ores and have less environmental impact than smelting
• Phytomining uses plants to absorb copper compounds from the ground. The plants are then burned to produce ash from which the copper can be extracted,
• Bioleaching uses bacteria to produce solutions containing certain copper compounds

Question 24

How else can copper be obtained?

Answer 24

From solutions of copper salts/compounds by reacting with a more reactive metal to displace the copper.

Copper can also be extracted from solutions of copper compounds by electrolysis.

Question 25

What are the three main ways of extracting copper from its compounds? (Plus 2 other ways)

Answer 25

1. Smelting
2. Electrolysis
3. Displacement

As well as phytomining and bioleaching

Question 26

What are the main properties of the transition metals?

Answer 26

• Good conductors of heat and electricity
• Strong but can be hammered or bent into shape
• Less reactive than alkali and alkali earth metals
• Most have high melting and boiling points (higher than Group 1)
• Form coloured compounds
• High densities

Question 27

What do the properties of transition metals make them useful for?

Answer 27

Building and making things

Question 28

Complete the sentence:

Most of the ___ we use are ___

Answer 28

Most of the metals we use are alloys

Question 29

What are the properties of copper and what are its uses?

Answer 29

• Very good conductor of heat
• Does not react with water
• Can be bent but is hard enough to keep its shape

These properties make it useful for making tanks in water/heating systems.

• Very good conductor of electricity as well.

Can also be used for electrical wiring (bendy)

Question 30

What are the uses of iron, gold, aluminium, and copper alloys?

Answer 30

• Iron is made into steels
• Gold is used in jewlery as an alloy
• Most of the aluminium used for buildings and aircraft is alloyed
• Copper alloys include bronze and brass (sculptures etc. + instruments!)

Question 31

What are the disadvantages of mining for metal ores?

Answer 31

• Involves digging up and processing large amounts of rock
• Produces large amounts of waste materials
• Effects large areas of the environment

Question 32

What are the advantages of recycling?

Answer 32

• Saves the energy needed to extract the metal from its ore
• Saves resources because less ore needs to be mined
• Less fossil fuel is needed to provide the energy to extract the metal from its ore

Question 33

What are the benefits of using metals in construction?

Answer 33

• Strong
• Can be bent into shape
• Can be made into flexible wires
• Good electrical conductors

Question 34

What are the drawbacks of using metals in construction?

Answer 34

• Obtaining metals from ores causes pollution
• Also uses up limited resources
• More expensive than other materials such as concrete
• Iron and steel can rust