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Flashcards in topic 10 resources Deck (47):
1

what is portable water

water that has been treated or is naturally safe for humans to drink

2

what does pure water contain

H2O molecules

3

why isn't portable water pure

because it contains lots of dissolved substances

4

what is the important thing to consider with portable water (3)

-that the levels of dissolved salts aren't too high
-that it has a pH between 6.5 and 8.5
-there isn't bacteria or microbes in the water

5

`what type of water is rainwater

``fresh water

6

what is fresh water

water that doesn't have much dissolved in it

7

what are the 2 ways that water can collect as

surface water (in lakes,rivers or as groundwater (in rocks called aquifers)

8

what does surface water tend to usually do

dry up first

9

so where does the water come from for warmer places

groundwater

10

what are the 2 ways that freshwater can be treated by

-filtration
-sterilisation

11

how is filtration used to treat freshwater

a wire mesh screens out large twigs and then gravel and sand beds filter out any solid bits

12

how is sterilisation used to treat freshwater

the water is sterilised to kill any harmful bacteria or microbes. this can be done by bubbling chlorine gas through it or by using ozone or ultraviolet light

13

how is seawater treated in some very hot countries if there isn't enough groundwater to provide portable water

by desalination

14

by what method can you test and purify a sample of water

by distillation

15

when you flush water where does the water go to

into the sewers and towards sewage treatment plants

16

what waste do agricultural systems produce

-nutrient run-off from fields
-slurry from animal farms

17

what must happen to sewage from domestic or agricultural sources and why

it has to be treated to remove any organic matter and harmful microbes before it is put back into freshwater sources like rivers

18

other than desalination, how else can seawater be treated

by a process that use membranes- reverse osmosis

19

how is seawater treated by membranes (steps)

-the salty water is passed through a MEMBRANE that only allows water molecules to pass through. Ions and larger molecules are TRAPPED by the membrane so separated from the water

20

why is distillation and reverse osmosis bad

-they require loads of energy so they are really expensive and are not practical for producing large quantities of fresh water

21

why is mining ores bad for the environment

because it uses loads of energy, scars the landscape, produces lots of waste and destroys habitats

22

2 examples of natural resources

cotton for clothing or oil for fuel

23

how can some natural products be replaced

by synthetic products or improved upon by man-made processes

24

how can rubber be extracted

by the sap of the tree

25

what can replace rubber

man-made polymers

26

what does agriculture provide

conditions where natural resources can be enhanced for our needs (development of fertilisers mean we can produce a high yield of crops)

27

2 examples of renewable energy resources

freshwater and food

28

what are finite resources

non-renewable resources

29

what are found in ores of the earth that makes them finite

minerals and metals

30

after being extracted, what do finite resources undergo

man-made processes to provide fuels and materials necessary for modern life (fractional distillation is used to provide fuels)

31

what is sustainable development

an approach to development that takes account of the needs of present society while not damaging the lives of future generations

32

why is extracting resources unsustainable

due to the amount of energy used and the waste produced

33

how is processing unsustainable

as it uses energy that is made from finite resources

34

how can we reduce the use of finite resources

-use less of it
-reduce the way it is produced

35

what have chemists developed in relation to using less finite resources

catalysts

36

what are catalysts used to do

reduce the amount of energy required for certain individual processes

37

how can we improve the sustainability of copper

by extracting it from low-grade ores (ores without much copper in)

38

what 2 low-grade methods are there for when extracting copper

-bioleaching
-phytomining

39

what is bioleaching

-bacteria are used to convert copper compounds in the ore into soluble copper compounds, separating out the copper from the ore in the process

40

what does the leachate (the solution produced by by bioleaching) contain

copper ions, which can be extracted

41

why is recycling metals good (3)

-uses much less energy than is needed to mine and extract new metal
-conserves the finite amount of each metal in the earth
-cuts down on the amount of waste getting sent to landfills

42

how are metals recycled

by melting them and then casting them into the shape of the new products

43

how can glass recycling help sustainability

by reducing the amount of energy needed to make new glass products and also the amount of waste created when used glass is thrown away.

44

how is glass separated before being recycled

by colour and chemical composition

45

how is glass reused (steps)

the glass is crushed and then melted to be reshaped for use in glass products

46

what does the life cycle assessment show about plastic bags

even though they are not "biodegradable", they can take less energy to make and have a longer lifespan than paper bags so they are less harmful to the environment.

47

why are some LCAs bad

they may only show some of the impacts of a product on the environment and also be biased as they can be written to deliberately support the claims of the company