C14- The Earth's resources Flashcards
Renewable resource definition and examples
Those that can be replenished in our lifetime as they are used up. Biofuel, solar energy
Finite resources definition and examples
Those that can’t be replenished in our lifetime, and will eventually run out. Oil, gas
Why is it hard to tell the time left before fossil fuels run out?
There is a lot of uncertainty in the calculations so are estimates
Natural resources
Found where?
3 key uses?
In nature
Food, timber, fuel
Finite resources
Are…?
2 key uses?
Processed
Energy, materials
4 examples of renewable materials
4 examples of finite resources
Wind, rubber, cotton, wood
Coal, polyethene, natural gas, oil
Potable meaning?
Water that is safe to drink (not necessarily pure)
3 steps to make potable water in the UK
-Choosing appropriate source of fresh water, e.g rivers, lakes
-Pass through filter beds to remove solid particles
-Sterilisation, adding chlorine/ozone or passing through UV light to reduce microbes
Why are these sources not suitable for drinking water..
Water from roads?
Estuary close to the sea?
River near factory?
Could contain impurities like oil
High conc of dissolved salts
Could have dissolved toxic chemicals
3 factors that make water unpotable
-Large amount of solid particles e.g soil
-High concs of dissolved substances e.g salt
-Disease causing microbes e.g bacteria
Key way of sourcing water in hot/dry countries?
2 processes?
Disadvantages?
Desalination
Distillation or reverse osmosis
-Require large amounts of energy, is expensive
3 parts to water analysis practical?
How to carry it out?
pH= use universal indicator & colour chart
Solids= record mass of evaporating basin, add 30cm3 of water sample. Heat over bunsen burner until dry then let cool. Record new mass, calc change in mass which = mass of dissolved solids.
Distillation= place water sample in conical flask. Use bung and delivery tube connected to a clamped boiling tube in beaker of ice water. Heat water over bunsen burner until boiling, wait until 1cm3 water in test tube. Then use blue cobalt chloride paper, should turn pink
3 types of sewage and what does each one contain?
Sewage- organic matter, harmful microbes
Agricultural- organic matter, harmful microbes
Industrial- organic matter, harmful chemicals
How is sewage waste treated?
- Screening- removes large objects and grit
- Sedimentation- produces sewage sludge and effluent
- Effluent= aerobic biological treatment
- Sewage sludge= anaerobic digestion
What happens to effluent and sewage sludge after being treated?
Effluent- released back into environment, e.g rivers
Sludge- used as fertiliser or renewable energy
2 ways to extract copper from high-grade copper ores and description
Displacement–> Scrap iron with copper sulfate
Smelting–> Heating copper ore to high temps
How to purify copper (detailed) and why?
Electrolysis–> pure Cu cathode, impure Cu anode. Smaller anode as ions move to shiny cathode. Sludge with unreactive metals at bottom of impure anode
Improve electrical conductivity
2 ways to extract copper from low-grade ores and description
Phytomining–> Plants grow on land containing copper, absorb copper ions, plants are burnt, ash reacted w acid to make solution
Bioleaching–> Bacteria breaks copper and sulfate bonds, forms stronger bonds between copper
Life Cycle Assessment
Used to?
Stages?
Assess environmental impact of the stages in a products life
1. Extraction & processing of raw materials
2. Manufacturing & packaging
3. Use and operation
4. Disposal at end of life
-Including transport at each stage
Why is the ease of transportation important in LCAs?
More products in one transport means less energy required
Aluminium
Raw material?
Extracted by?
Processed?
Ore
Mined and crushed
Melting, electrolysis
Glass
Raw material?
Extracted by?
Processed?
Silica
Mined and crushed
Melted w other things
Steel
Raw material?
Extracted by?
Processed?
Iron ore
Mined and crushed
Smelted with coke
Ceramics
Raw material?
Extracted by?
Processed?
Clay
Mined and crushed
Shaped, heated in oven
Building materials
Raw material?
Extracted by?
Processed?
Clay, limestone
Mined and crushed
Shaped, heated in oven
Plastics
Raw material?
Extracted by?
Processed?
Crude oil
Drilling
Fractional distillation, cracking
Why do we reduce the use of resources?
-Conserve limited raw materials
-Reduce mining and its environmental impact
2 examples of reusing materials
Glass bottles can be repurposed
Copper can be reshaped
How to recycle glass bottles and copper?
Glass- Crushing and melting into dif products
Copper- Melting into dif products
Sustainability
Meeting needs of the present without compromising the ability of future generations
3 ways science can help to reduce use of materials?
-Design products with longer life span
-Design more energy efficient production methods
-Find dif resources to make a product
