sc11, obtaining and using metals (paper 1)

Question 1

state the order of metals from most reactive to least reactive

Answer 1

• potassium
• sodium
• calcium
• magnesium
• aluminium
• carbon
• zinc
• iron
• tin
• lead
• hydrogen
• copper
• silver
• gold

Question 2

mnemonic for metal reactivity

Answer 2

please stop calling me a careless zebra instead try learning how copper saves gold

Question 3

what does a metal and water produce

Answer 3

metal hydroxide + hydrogen

Question 4

what does a metal and acid produce

Answer 4

salt + hydrogen

Question 5

is the rate of reaction greater in warm acids or cold acids

Answer 5

warm acids

Question 6

true or false: the more reactive the metal, the easier it forms cations

Answer 6

true

Question 7

true or false: the more reactive the metal, the harder it forms cations

Answer 7

false

Question 8

what is an ore

Answer 8

a rock that contains enough of a compounds to extract a metal for profit

Question 9

how can we extract metals less reactive than carbon

Answer 9

through reduction by heating it with carbon

Question 10

why don’t we often reduce copper oxide to copper with hydrogen

Answer 10

because it’s hazardous

Question 11

how can we reduce iron oxide

Answer 11

using carbon in a blast surface

Question 12

give the word equation for reducing iron oxide using carbon in a blast surface

Answer 12

iron oxide + carbon –> (molten) iron + carbon monoxide

Question 13

give the symbol equation for reducing iron oxide using carbon in a blast surface

Answer 13

Fe2O3 (s) + 3C (s) –> 2Fe (l) + 3CO (g)

Question 14

how else can we reduce iron oxide except using carbon in a blast surface

Answer 14

reduce by carbon monoxide

Question 15

give the word equation for reducing iron oxide using carbon monoxide

Answer 15

iron oxide + carbon monoxide –> (molten) iron + carbon dioxide

Question 16

give the symbol equation for reducing iron oxide using carbon monoxide

Answer 16

Fe2O3 (s) + 3CO (g) –> 2Fe (l) + 3CO2 (g)

Question 17

for metals more reactive than carbon, how do we extract it

Answer 17

electrolysis

Question 18

true or false: a high grade ore means a high proportion of metal/metal compounds

Answer 18

true

Question 19

true or false: a low grade ore means a low proportion of metal/metal compounds

Answer 19

true

Question 20

true or false: a high grade ore means a low proportion of metal/metal compounds

Answer 20

false

Question 21

true or false: a low grade ore means a high proportion of metal/metal compounds

Answer 21

false

Question 22

general properties of low grade ores

Answer 22

• more common
• less profitable
• use more energy
• produce more waste when used

Question 23

what are the two biological methods of extracting metal from ores

Answer 23

phytoextraction and bioleaching

Question 24

steps of phytoextraction

Answer 24

• grow plants that absorb metal compounds in roots
• plants concentrate metal compounds in its shoots and leaves
• plant is burned to form ash
• from which the metal is extracted from

Question 25

steps of bioleaching

Answer 25

- using bacteria grown on a low grade ore - that produces a solution containing metal ions, called leachate - metal is extracted from the leachate using scrap iron

Question 26

advantages of bioleaching

Answer 26

cheaper

Question 27

disadvantages of bioleaching

Answer 27

- slow - produces toxic substances (e.g sulfuric acid)

Question 28

advantages of phytoextraction

Answer 28

doesn't cause mining problems

Question 29

disadvantages of phytoextraction

Answer 29

slow

Question 30

why are we using biological methods for extracting metals

Answer 30

- we are running out of high grade copper ores - electrolysis is too expensive for low grade ores

Question 31

what is corrosion

Answer 31

- when a metal reacts with surrounding substnces such as air and water - making the metal weaker over time - also a result from oxidation

Question 32

true or false: more reactive metals easily corrode

Answer 32

true

Question 33

true or false: less reactive metals easily corrode

Answer 33

false

Question 34

what is the corrosion of iron and steel called

Answer 34

rusting

Question 35

what does rusting require

Answer 35

oxygen and water

Question 36

why doesn't aluminium corrode

Answer 36

their surfaces have a protective oxide layer in tarnish which prevents further reactions

Question 37

define tarnish

Answer 37

not shiny

Question 38

why are unreactive metals found in their native state

Answer 38

they can't combine or react with other metals

Question 39

true or false: carbon cannot reduce metals more reactive than itself

Answer 39

true

Question 40

true or false: carbon can reduce metals more reactive than itself

Answer 40

false

Question 41

disadvantages of extracting metals from their ores

Answer 41

- uses up limites resources - uses a lot of energy - damages the environment (waste rock and carbon dioxide)

Question 42

advantages of recycling metals

Answer 42

- metal ores last longer - less energy is needed - less land - less noise and dust - fewer quarries and mines - saved energy

Question 43

disadvantages of recycling metals

Answer 43

- used metal itoms must be collected and transported to the recycling centre - different metals must be removed from used items and sorted - recycling saved different amounts of energy, depending on the metal involved

Question 44

what does LCA stand for

Answer 44

life-cycle assessment

Question 45

steps of LCA

Answer 45

- obtaining raw materials - manufacturing the product - using the product - disposing of the producr

Question 46

what data does LCA NEED

Answer 46

- use of energy - release of waste materials - transport/storage in most/all stages

Question 47

what data does LCA LIKELY to need

Answer 47

- whether the raw materials are renewable or non-renewable - if the product can be recycled or re-used - how the product is disposed of

Question 48

reasons for obtaining LCA's

Answer 48

- identifying alternative materials with less impact - identify a stage which could be improved