using resources Flashcards
what type of water is safe to drink?
potable water
what is pure water
water that has no dissolved substances
ONLY H2O
where can potable water come from?
- fresh water like rain, rivers
how to get potable water
- filter beds
- sterilise
ways of sterilising water
- chlorine
- ozone
- uv
if fresh water scarce how is sea water turned to potable water
and the two types and problem
desalination
- reverse osmosis- through membrane
- distilation- lots of energy- money
example of natural product replaced by synthetic products
- rubber
- ^sap from trees
- to crude oil
how is waste water treated
- screened through mesh to get rid of insoluble products
- sedimentation- turning into liquid effluent and ludge
- liquid effluent:
- gas bubble dtrhough for aerobic bacteria to digest organic matter & microorganism
- sludge:
- anaerboic bacteia digest- producing biogas which gets burned for eeectricty
- the rest of the sludge is used as fertilsier
2 ways ti exrat copper compounds
phytomining
bioleaching
phytomining
- plants grow on land containg copper
- copper is absorbed
- planst are harvested and burned
- the ash contains copper
bioleaching
baceria breaks the nbonds btween the ore and copper
how is copper extracted from copper compounds
- displavced by iron
- electroloysis
what do life cycle assessments assess
the environmental impact of:
- extracting & processing raw materials
- manufactoring
- product during its lifetimes
- disposal
issues with metals & plastics
plastics- polymers- crude oil- cracked- energy- fossil fuels
metals- ores mined- extraction- energy
^ transport
environemntals impacts with disposal
- chemicals- energy
- transportation to landfills etc
plastic vs paper bags
LCA
plastic- cru oil which can leak detsrying habitats
paper- trees, renewable, sestructieto habitats
plastic- strong
paper- not strong
transportation- energy
plastic- non biodegradable
issue with LCA
biased
not always accurate
what is corrosion
destruction of materials by chemical reactions with substances in the environment
what can rust
ONLY iron and alloys of iron like steel
describe experiment for rusting
3 test tubes
1. iron nail in distilled water- water & air
2. iron nail in BOILED distilled water removed sissolved air) WITH oil on top water & no air
3. iron nail in anhydrogous calcium chloride (removed water from air) WITh rubber bung- no water & just air
rusts ONLY IN no.1- rusting needs water & air
how to stop erosion
barriers
- grease
- paint
- electroplaing- coating in metal
what metal can coat to stop erosion
aluminium- aluminium oxide
sacrificial protection
coating that contain more reactive metal
EXAMPLE
- zinc to galvanise steel
bronze
alloy of
- copper
- tin
brass
alloy of
- copper
- zinc
gold alloy
and proportion of gold in alloy
- silver
- copper
- zinc
measured in carats
24 carat- 100%
18 carat- 75%
steel
- iron
- ! carbon
high carbon steel vs low carbon
high- strong but britle
low- soft and more easily shaped
stainless steel
steel containing:
- nickel
- chromium
- hard and resitant to corrosion
low density alloys
alumium alloys
materials we produe using raw materials
5
- glass
- metal
- building materials
- plastics
why do we need to reduce the need for raw materials?
quarrying- dust & destrots habitats
mining- harmful chemicals
and reqires lots of energy to urn ino useul products
^ fossl fuels
how to reduce need for raw materials?
eg
glass
metal
plastic bottle
- reuse
- recycle
! - glass- reuse, crushed
- plastic bottles- fleece jackets, carpets
- metals- meleted recastes
- HOWEVER diff metals may need to be seperatued
- ^ srap steel- redue use of rion
2 types of glass- differences and how made
- soda lime glass- sand + sodium carbonate + limestone -low melting point
- borosilicate- sand + boron trioxide- high metling point
how is clay ceramics produced
- clay- mineral found in ground- wet- shaped- heated in furnace eto harden
- for pottery
- bricks
what make up composites
2 different materials
- reinforcement- fibres or fragments of material
- bround by matric/binder materials
2 examples of composites
- carbon fibre composite- carbon binded by plastics
- reinforced concrete- steel binded by concrete
low density polythene
vs
high denisty polythene
LD- softer than HD
both made from monomer ethene
just different condition
what conditons cn change properties of plymers
- reaction temperature
- reaction pressue
- catalyst
thermosoftening vs thermosetting
thermosoftening- polymer strands connected by intermoleular forces that break when heated
thermosetting- polymer strands connected by strong crosslinks that DONT break when heated
what is the haber process used for?
to manufacture ammonia which can be used to produced nitrogen based fertilisers
how are the raw materials of Haber process produced?
- nitrogen- air
- hydrogen- methane with steam
equation for haber process
N2 (g) + 3H2 (g) <> 2NH3 (g)
REVERSIBLE
conditions for Haber process and why
- iron catalyst- ^ rate of reaction
- high tmperature- > exothermic, needs cool temperatures, but that SLOWS reaction - 450C
- high pressure needed to move equillibrium to right- but DANGEROUS, expensive 200 atmospheres
how is ammonia removed`
cooled and liquifyies
NPK fertilisers compounds
NITROGEN
PHOSPHOROUS
POTASSIUM -K
what is NPK fertiliers
form….
formulations of different salts
nitrogen compound
ammonium nitrate NH4NO3
- ammonia- haber process
- ^ used to make nitric acid
- ^ add more ammonia-> ammonium nitrate
potassium compounds
potassium chloride
poassium sulfate
MINED
phosphate rock + nitric acid
phosphoric acid + calcium nitrate
- phosphoric acid + ammonia (nautrilised) -> ammonium phosphate
phosphate rock + sulfuric acid
calcium phosphate + calcium sulfate
^ mixture- single superphosphate
phosphate rock + phosphuric acid
triple superphosphate
phosphate in NPK
from phosphate rock
cant just used phosphate
- nitric acid
- sulfuric acid
- phosphoric acid
ammonium nitrate neatralistaion reaction in school lavs vs industriall
labs- diluc nitric acid & ammonia
industry- ammonia gas, concntrated nitric acid
^ dangerous, very exo, lot of heat
labs- cystals ove water bath using bunsen burner- lot of energy
industry- eapouraton energy from reaction
labs- small amounts- batch process
industry- continous process
