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Question 1

How are displacement reactions redox reactions?

Answer 1

• more reactive metals form a cation as they displace the less reactive metal (oxidation)
• less reactive metals, when they are displaced, forms an atom (reduction)

Question 2

What is formed when metals react with other substances?

Answer 2

Positive ions

Question 3

Where are most metals extracted from?

Answer 3

ores found in earth’s crust

Question 4

Reduction and oxidation can be the gain and loss of oxygen as well - T or F

Answer 4

TRUE

Question 5

What does the extraction of metal involve?

Answer 5

The reduction of ores (gaining oxygen to form more reactive metal + oxygen)

Question 6

When are metals extracted by electrolysis?

Answer 6

When the metal is higher than carbon in the reactivity series

Question 7

What is the advantages and disadvantages of phytoextraction (extracting metals from plants)?

Answer 7

Advantages —
—> no harmful gases produced
—> less damage than mining
—> can extract metals from contaminated soils

Disadvantages —
—> more expensive than mining
—> growing plants depend on weather
—> very slow

Question 8

What are the advantages and disadvantages of using bioleaching (extracting metals from bacteria)?

Answer 8

Advantages —
—> no harmful gases produced
—> doesn’t require high temperatures
—> causing less damage than mining

Disadvantages —
—> toxic substances can be produced
—> very slow

Question 9

how is a metal’s relative resistance to oxidation related to its position in the reactivity series?

Answer 9

the less reactive a metal is, the more resistant it is to oxidation (loss of electrons)

Question 10

what is a life cycle assessment?

Answer 10

assesses the environmental impact of products in the stages:

• extracting and processing raw materials
• manufacturing and packaging
• using the product
• disposal of the product when it’s not useful

Question 11

what are the advantages of recycling a metal rather than extracting them from their ores?

Answer 11

• recycling conserves natural resources
• less energy used
• conserves fossil fuels
• less damage to habitats
• produces less CO2
• CO2 is a greenhouse gas
• avoids using large amounts of electricity
• electricity is expensive

Question 12

what experiments can be done to determine the order of reactivity of metals by displacement reactions?

Answer 12

1. places separate pieces of each metal into solutions of each salt
2. observe changes in colour of metal
3. more reactive metal = greater number of reactions

Question 13

how can growing plants result in the phytoextraction of copper?

Answer 13

• plants absorb copper ions from ores
• plants are then burned