P2 10 Global resources

• oxygen in air • food+water • warmth • shelter • transport

development which meets the needs of present generation without affecting the needs of future generations

improve industrial processes: * catalysts - speed up chemical reactions so less energy input required * development of carbon nanotubes - strengthens materials, extends its life improve agricultural processes: * developing pesticides that break down - don’t enter food chains or pollute environment * smart materials added to soil - able to retain water itself

• water that is safe to drink • contains a safe level of dissolved salts + microbes • used for drinking/ washing/ cooking/ industrial processes

• water allowed to settle - large particles settle at bottom and water drawn out the top • water passed through filter beds - removes small particles • water is sterilised using chlorine/ozone/UV - kills most bacteria

desalination using simple distillation 1. mixture in flask heated until water boils and turns into vapour 2. vapour cools+ condenses in the condenser 3. pure water (distillate) is collected in a beaker, salt remains in flask -> alternative method is reverse osmosis

requires large amounts of energy - expensive

• place litmus paper in a drop of each sample and record pH • measure the mass of a watch glass before+after placing a drop of each sample in it, then find the difference for the mass of dissolved solids

• domestic: cleaning/washing, sewage, harmful bacteria+ organic matter • agriculture: water used for irrigation contains pesticides/fertilisers • industry: energy production/ manufacturing, organic matter, chemicals, oil

• screening: large sediment/grit removed by metal grid • sedimentation: sediments allowed to settle to bottom forming sewage sludge, effluent floats to top • anaerobic digestion: sewage sludge is dried+ anaerobically digested by bacteria -> bacteria produces methane during digestion, burned for energy • aerobic treatment: effluent drained into a tank, oxygen bubbled through so good bacteria break down harmful bacteria • treated water released back into environment

uses a lot of resources/equipment for each stage

• an assessment of a product’s environmental impact at every stage of its life • helps identify areas which neg. impact environment and make changes to a product to make it more sustainable/ reduce carbon footprint

• extraction/processing: finite/infinite source? damage to environment/pollution? energy needed to extract? • manufacture+packaging: energy needed to make? harmful waste products produced/pollution? can packaging be recycled? • usage: single-use or long-lasting? energy needed to operate? • disposal: reusable/recyclable? sent to landfill? biodegradeable? energy used to incinerate? pollution? ++ conclusion - can be either pos or neg

• figures used to assess products are often biased - based on value judgements • LCAs are sometimes misused - can be selective/shortened, eg. for advertising, to reach preferred conclusions and make a product appear more sustainable

• extraction/processing: paper made from sustainable trees but require a lot of energy to process, plastic made from crude oil which is finite • manufacturing/packaging: plastic bags used less energy+water during manufacture • usage: paper bags not strong/ long-lasting/ waterproof, plastic bags reusable for other purposes • disposal: paper is biodegradeable+ recyclable, plastic not biodegradeable so go to landfill, can be recycled • conclusion: plastic bags are more sustainable as they have a longer life and use less energy during manufacture

• recycling: requires less energy/pollution than extraction, eg. metal is melted to make new products • reuse: eg. glass is crushed+melted to make new products • repair: fix products rather than purchasing new ones • reduce amount of resources used

a rock containing minerals from which metals are extracted for profit

• phytomining- extracting copper from soil by burning plants • bioleaching- using bacteria to extract copper from copper compounds -> doesn’t require digging/displacement of rock so more sustainable - no damage to landscape, doesn’t cause tremors -> phytomining is carbon neutral - plants absorb CO2 when growing, then release when burned

used to extract copper from copper compounds in soil 1. plants absorb copper ions from soil through roots 2. plants containing copper compounds are burned 3. copper is extracted from the ash using electrolysis or displacement with scrap iron

• bacteria breaks down+ absorbs copper ions • bacteria excrete a metal solution (leachate) containing copper compounds • copper is extracted using electrolysis or displacement with scrap iron