C14:TheEarth'sResources

Question 1

why do we rely on the earths resources

Answer 1

to make new products and provide us with energy

Question 2

finite definition

Answer 2

resources that will eventually run out if we continue to exploit them

Question 3

example of a finite resource

Answer 3

fossil fuels

Question 4

renewable definition

Answer 4

resources that can be replaced as we use them up

Question 5

example of a renewable resource

Answer 5

crops used to make biofuels

Question 6

why can estimates of how long fossil fuels have left only be a rough estimate

Answer 6

because of the uncertainty involved in calculations

Question 7

potable water

Answer 7

water that is safe to drink

Question 8

how is water made fit to drink

Answer 8

by passing it through filter beds, adding chlorine or ozone or UV light through it

Question 9

why is water passed through filter beds

Answer 9

to remove any solids

Question 10

why is chlorine/ozone/UV light used in water treatment

Answer 10

to remove any microbes-sterilisation

Question 11

why isn’t our drinking water made by distillation

Answer 11

as it requires a large amount of energy which makes it expensive

Question 12

how can water be made fit to drink by reverse osmosis

Answer 12

by using membranes to separate dissolved salts from salty water but this method of desalination also uses energy to get the high pressure conditions needed

Question 13

where does wastewater require treatment before being released into the environment

Answer 13

sewage works

Question 14

what does sewage treatment involve

Answer 14

the removal of organic matter and harmful microorganisms and chemicals

Question 15

name the stages of sewage treatment

Answer 15

screening, sedimentation, aerobic biological treatment

Question 16

what happens in screening

Answer 16

the removal of large solids and grit

Question 17

what happens in sedimentation

Answer 17

production of sewage sludge

Question 18

what happens in the aerobic biological treatment phase

Answer 18

safe effluent released into the environment

Question 19

effluent definition

Answer 19

watery liquid

Question 20

what happens to the sewage sludge

Answer 20

it is separated, broken down by anaerobic digestion and dried

Question 21

what can the sludge be used for

Answer 21

fertiliser and a source of renewable energy

Question 22

how is most copper extracted

Answer 22

by smelting copper rich ores

Question 23

what is happening to the amount of copper

Answer 23

becoming more scarce

Question 24

what can electrolysis be used for with copper

Answer 24

purify impure copper e.g. copper metal obtained from smelting

Question 25

how can copper be extracted from solutions of copper compounds

Answer 25

by electrolysis or displacement

Question 26

2 ways scientists have developed to extract copper from low-grade ores

Answer 26

bioleaching and phytomining

Question 27

what is used in bio-leaching

Answer 27

bacteria

Question 28

what is used in phytomining

Answer 28

plants

Question 29

explain phytomining

Answer 29

plants that absorb copper are planted on soil containing low-grade copper ores, the plants are burned and copper is extracted from copper compounds in the ash, leachate is then made, electrolysis makes pure copper

Question 30

how can copper ions be "leached"

Answer 30

dissolved by adding sulfuric acid to make leachate of copper sulfate

Question 31

explain bio-leaching

Answer 31

bacteria feed on low-grade ores, leachate is obtained, scrap iron and electrolysis is used to extract the copper from the leachate

Question 32

how much copper comes from bioleaching

Answer 32

20%

Question 33

what are LCAs

Answer 33

life cycle assessments

Question 34

what are LCAs used for

Answer 34

to assess the environmental impact of products, processes or services

Question 35

what do LCAs analyse

Answer 35

each of the stages of a life cycle from extracting and processing raw material to disposal at the end of its life including transportation and distribution at each stage

Question 36

what is data available for

Answer 36

the use of energy, water, resources and production of some wastes

Question 37

by assigning numerical values to the relative effect of pollutants involves what

Answer 37

subjective judgements

Question 38

what are subjective judgements

Answer 38

judgements that are relative to the person making the judgement

Question 39

what is the aim of reduce reuse recycle

Answer 39

to reduce our use of limited resources, energy and the waste we produce

Question 40

what does recycling material save

Answer 40

energy and our limited finite metal ores, pollution is also reduced by recycling