C10 Flashcards
What do we use the Earth’s resources for?
Warmth, shelter, food and transport
How do we use agriculture to maximise these resources?
To provide food, timber, clothing and fuel
What does the term finite mean?
There is a limited amount so we will run out of it eventually
What is potable water?
Water that is safe to drink
What does water need to have to be classed as potable?
Low enough levels of dissolved salts and microbes
How can fresh water be made potable?
Filtering the water through filter beds and then sterilising it
How can water be sterilised?
Using chlorine, ozone of UV light
How can salt water be made potable?
Remove the salt by distillation or reverse osmosis
Why fresh water a better source of potable water than salt water?
It requires less energy to make potable
How are potable and pure water different?
Pure water has no other chemicals in it, potable has other chemicals in it but at low enough levels so it is safe to drink
How is sewage treated before being released into the environment?
Screening and grit removal, sedimentation, anaerobic digestion of sewage sludge, aerobic treatment of effluent
Why is fresh water a better source of potable water than waste water?
There are a lot more stages in making waste water potable
What are low grade copper ores?
Rocks that have a small percentage of copper in them
Why are new methods of extraction needed?
Traditional methods of digging, moving and disposing of large amounts of rock are more expensive, use lots of fuel and produce lots of waste.
What is phytomining?
Using plants to absorb metal compounds from the ground. The plants are harvested and then burned to produce ash that contains metal compounds
