C12 The Earth's Resources Flashcards
What is a finite resource
Resources that are being used up faster thenthey can be replaced
What is a synthetic product
Products which supplement or replace natural products
Examples of finite resources
Coal, natural gas, crude oil
What is a renewable resource
Resources that can be replaced at the same rate at which they are used up.
Examples of renewable resources
Cotton, solar power and wood
Examples of a synthetic product
Polyester, nylon, acrylic resin
Stage 1 of waste water treatment
Screening and grit removal- Large solids and grit removed
Stage 2 of waste water treatment
Primary sedimentation tanks-Organic waste sinks to bottom as sludge. Remaining water (effluent) taken from the top.
Stage 3 of waste water treatment
Aeration-Good bacteria kill harmful bacteria in aeration tanks where air is pumped through effluent.
Stage 4 of waste water treatment
Final settling tanks-Good bacteria sink to bottom in sludge.
Stage 5 of waste water treatment
Sludge treatment-Anaerobic digestion of sludge by bacteria.
Stage 6 of waste water treatment
Burners-Methane burned for heat and electricity generation.
What is pure water
Water that is 100% water and contains nothing else
What is potable water
What that is fit to drink-contains low levels of microbes and dissolved substances
What is waste water
Used water from homes, industry and agriculture-contains high levels of microbes and contains dissolved substances.
What is fresh water
Water in underground streams and rocks, rivers, lakes,ice caps and glaciers. Contains low levels of microbes and very low levels of dissolved substances.
What is ground water
Water in underground streams and rocks. Contains low levels of microbes and contains dissolved substances
What is sea water
Water in the seas and oceans. It contains high levels of microbes and contains dissolved substances.
Ways of making potable water from fresh water
Filtration-removes solids
Sterilisation-kills microbes-done by adding chlorine or treating with ozone or using uv light.
ways of making potable water from sea water
Distillation and reverse osmosis
What is an ore
A rock containing metal
What is a high grade and low grade ore
High grade-high % of metal
Low grade-low % of metal
Two methods of metal extraction
Phytomining and bioleaching-both avoid traditional methods of mining
What is phytomining
- Using plants to absorb metal compounds from low grade ore.
- Plants are harvested and burnt. The metal compounds are extracted from the ash.
What is bioleaching
Bacteria feed on low grade metal ores to produce a solution of copper ions-leachate
What is a redox reaction
Reduction and oxidisation
What is a cathode and what is an anode
Cathode-negative non-metal ion
Anode-positive metal ion
What stages of a products life does a Life Cycle Assessment (LCA) work out the environmental impact
Extracting and processing raw materials, manufacturing and packaging, use and reuse, dispose.
What are value judgements
Scores that an individual comes up with to measure impact
Examples of limited raw materials
Metals, building materials, glass, ceramics and plastic.
Impacts on the environment of quarrying and mining
Noise, dust, visual pollution and it destroys habitats.
What is sustainable development
Meeting the needs of current generations without compromising the ability of future generations to meet their own needs.
What are the three Rs
Reuse-less demand for new products.
Reduce-less amount of waste produced
Recycle-less new materials are needed.
How can scrap steel be recycled
By adding scrap steel to the iron from a blast furnace.
Step 1 of purifying test water practical
Each sample of water is tested using universal indicator to find the pH of the water.
pH- < 7 are acidic
pH- > 7 are alkaline
pH- = 7 is neutral
Step 2 of purifying test water practical
A clean, dry watch is weighed. You can use the same watch glass in step 3 providing you wash and dry it each time.
Step 3 of purifying test water practical
Each water sample is tested for the presence of dissolved solids. This is done by placing 5cm’ of the water in the watch glass and gently heating it over a beaker of boiling water to evaporate the water and leave any dissolved on the watch glass. The watch glass is then weighed again to find the mass of any dissolved solids.
Step 4 of purifying test water practical
The sea water is distilled. Steam from the boiling sea water passes through the delivery tube and condenses to liquid water in the cooled test tube. Any dissolved solids present remain in the conical flask.
Step 5 of purifying test water practical
A portion of distillate from step 4 is tested for pH.
Step 6 of purifying test water practical
A portion of distillate from step 4 is tested for the presence of dissolved solids.
