✅ 616 - extracting metals

Question 1

define an ore

Answer 1

a mineral or rock that contains a enough metal/metal compound to make it economical to extract the metal

(= the value of the metal is more than the cost of extracting it)

Question 2

what is the ore to extract copper (carbonate)?

Answer 2

malechite

Question 3

what is the ore to extract iron(III) (oxide)?

Answer 3

haematite

Question 4

what is the ore to extract aluminium (oxide)?

Answer 4

bauxite

Question 5

describe the 3 main stages to extract a metal

Answer 5

1) ore is mined

2) ore is processed
(metal compound separated from other substances in the ore)

3) metal is extracted from the pure metal compound using chemical reactions

Question 6

what is the mneunomic to remember the metal reactivity series?

(and what does each stand for - in terms of elements)

Answer 6

cute - carbon (NOT METAL)

has - hydrogen (NOT METAL, USED FOR REFERENCE)

Please stop calling me a (cute) zebra, I think love has copper silver gold platinum

Question 7

What extraction methods are there - when are they used

Answer 7

• in principle, all metals could be extracted from their compounds using electrolysis, but electricity is expensive
• if metal is less reactive than carbon, cheaper methods are used instead
• copper + iron are less reactive than carbon, so they can be extracted by heating their compounds with carbon or with carbon monoxide

Question 8

all metals can be extracted from their compounds using …… but is expensive

Answer 8

electrolysis (electricity is expensive)

Question 9

why can copper be extracted using carbon, but not sodium?

Answer 9

as copper is less reactive than carbon
- wheras sodium is too reactive to be extracted by reduction

Question 10

describe the 2 main steps of how copper is extracted from copper sulfide

(and the word and symbol equation for each one)

Answer 10

1) copper sulfide (II) is ‘roasted’ in air
(to get it into metal oxide form for carbon to reduce later) :

copper(II) sulfide + oxygen -> copper(II) oxide + sulfur dioxide
2CuS(s) + 3O2 (g) -> 2CuO(s) + 2SO2 (g)

2) copper(II) oxide is heated with carbon:

copper (II) oxide + carbon -> copper + carbon dioxide
2CuO(s) + C(s) -> 2Cu(s) + CO2 (g)

Question 11

explain how the extraction of copper sulfide is a redox reaction
- and what is the reducing agent

Answer 11

• copper(II) oxide loses oxygen and is reduced
• carbon gains oxygen and is oxidised
• carbon is acting as a reducing agent (reduced copper oxide to copper)

Question 12

what form of carbon is used when extracting copper from copper sulfide?

Answer 12

charcoal

Question 13

What does the method chosen to extract a metal depend upon

Answer 13

Its position in the reactivity series

Question 14

Extracting metals topic:

Copper(II) oxide can also be reduced to copper by heating it with __ or with __
(Rather than carbon)

Answer 14

Methane, hydrogen

Question 15

5 steps to reduce copper(II) oxide using charcoal, which is mostly carbon.

+ 2 considerations

Answer 15

1 - mix the two powders in a crucible, replace the lid. The lid must be kept on the crucible during heating to stop the powders escaping and to stop air getting in (because then the carbon would burn)

2- heat it strongly

3 - after several minutes, allow the crucible to cool

4 - when the crucible is cool, transfer its contents to a beaker of water. The copper sinks to the bottom while excess charcoal is suspended in the water

5 - separate the copper by washing it

• excess charcoal powder is used to ensure that all of the copper(II) oxide is reduced to copper
• eye protection should be worn throughout this practcial

Question 16

Overall extracting copper - pb

Answer 16