Using resources Flashcards
What is potable water?
Water that is safe to drink
What is pure water?
Water that only contains water molecules
How is is potable water produced from ground water?
Water is filtered to remove insoluble solids, then sterilised to kill harmful bacteria
What can be used to sterilise water?
Cl, ozone or UV light
How is potable water produced from salt water?
Distillation or reverse osmosis
How is potable water obtained from distillation?
Salt water is heated to 100oC, water evaporates + condenses to form pure water
How is potable water obtained from reverse osmosis?
Salt water is passed through a semi-permeable membrane, water molecules pass through but dissolved substances don’t
How is waste water treated?
Screening to remove large insoluble solids, sedimentation to remove small insoluble solids, aerobic biological treatment to remove organic matter+harmful bacteria, sterilisation
What are the stages of a life cycle assessment?
Extracting + processing raw material, manufacturing + packaging, use, disposal
What factors need to be considered when making a life cycle assessment?
Source of raw material, energy needed, water needed, pollutants produced
What is high grade copper ore?
High % of copper, very fast reactions, less environmentally friendly
What is low grade copper ore?
Low % of copper, very slow reactions, more environmentally friendly
How can copper be extracted from low grade ore?
Phytomining + bioleaching
How does phytomining work?
Plants are grown in soil containing low grade copper ore + absorb copper, plants are harvested + burnt then high grade copper extracted from ash
