C12- Using resources ♻️ Flashcards
What are examples of how humans use resources ?
- humans use resources to:
- provide warmth
- provide shelter
- provide food
- and, provide transport
What’s an example of a natural resource, that is supplemented by agricultural products ?
- in agriculture, cotton is produced from cotton plants; modern agriculture allows us to grow enough cotton, to meet the needs of the world
What’s an example of a natural resource, that is supplemented by synthetic products ?
- natural rubber comes from the sap of a tree; synthetic rubber can be produced using crude oil
What is a finite resource ?
- a finite resource, is a resource that cannot be replenished at the rate which it is used because, it will eventually run out
What are finite resources from the Earth, oceans and atmosphere used for ?
- finite resources from the Earth, oceans and atmosphere can be processed to produce energy and materials
Why are metals a finite resource ?
- metals are a finite resource because, huge amounts of metal is extracted from the Earth’s crust, which means if metals are contuined to be used at this rate, they will then run out
[Easy] What is a renewable resource ?
- a renewable resource, is a resource that can be replenished at the rate which it is used because it will never run out
What does ‘sustainable development’ mean ?
- sustainable development, is development that meets the needs of future generations, without compromising the ability of future generations to meet their own needs
Name three examples, of how chemistry plays a role in how we use resources ?
- artificial fertilisers allow us to grow more food with the land available
- chemistry allows us to provide water that is safe to drink
- and, processes such as phytomining and bio leaching help us to extract metals more efficiently
What type of water can humans drink ?
- humans can only drink water that has sufficiently low levels of dissolved salts [e.g- sodium chloride]
- and, humans can only drink water that dosen’t have high levels of microbes [e.g- bacteria]
What is potable water ?
- potable water, is water that is safe to drink
What is the difference between pure 🆚 potable water ?
- pure water, is water that contains no dissolved substances at all
- ; potable water, is water that is safe to drink [and contains dissolved substances, in small amounts]
Why does rain water provide most of our potable water in the UK ?
- because rain water contains low levels of dissolved substances [freshwater]
Where does freshwater collect ?
- freshwater collects in the ground, in aquifers [which is known as groundwater]
- and, rainwater also collects in: lakes, rivers and reservoirs
How is potable water produced ?
- an appropriate source of water is chosen [e.g- freshwater from rivers]
- the appropriate source of water is then passed through filter beds, to remove materials [such as leaves and suspended
particles] - the appropriate source of water is then sterilised, to remove microbes [by using chlorine, ozone or ultraviolet light]
How is water sterilised in the UK ?
- in the UK, water is sterilised by using chlorine
Name two ways that saltwater can be treated
- desalination, by using distillation
- and, desalination by using reverse osmosis [when water is passed through membranes]
Why might desalination be used ?
- desalination is used in countries where supplies of freshwater are limited [because the only available water may be too salty]
How does desalination produce potable water ?
Hint: minerals
- desalination reduces the levels of dissolved minerals, to an acceptable level for potable water
Describe the process of reverse osmosis
- water is put under high pressure and passed through a membrane
which has tiny pores [holes] in it. - these pores allow water
molecules through, but prevent most
ions and molecules from passing through.
What is a disadvantage of desalination ?
- desalination is very expensive because, it requires large amounts of energy
