C14 - The Earth's Resources Flashcards
Where do natural resources come from ?
Earth, sea and air
What can natural products be replaced by ? And give some examples
Some natural products can be replaced synthetic products or improved upon by man-made processes.
For example, rubber is a natural product that can be extracted from the sap of a tree however man-made polymers have now been made which can replace rubber in uses such as tyres
Synthetic products make it so that the natural products last longer as you would be using synthetic instead of natural
What does agriculture provide conditions for ?
Agriculture provides conditions where natural resources can be enhanced for our needs
What are finite resources ?
They are resources that are used up faster than they can be replaced
Renewable resource def
A renewable resources reform at a similar rate to or faster than we use them
What are 3 examples of finite resources ?
Metals, plastics and fossil fuels
Give 3 examples of renewable resources ?
Timber, cotton, rubber
What are 3 examples of synthetic products ?
Polyesters, PVC, nylon
How to purify water practical (RP)
Explain how to do it
- Use the universal indicator paper to measure the pH of the water sample.
- Accurately weigh an empty evaporating basin and record to two decimal places.
- Pour 10 cm° of water sample 1 into the evaporating basin.
- Heat the evaporating basin on a tripod and gauze using a Bunsen burner until the solids star to form and the majority of water has evaporated
- Weigh the cooled evaporating basin again and calculate the mass of the solids that were dissolved in the water.
- Record your results in a table:
What is potable water ?
Potable water is water that’s been treated or is naturally safe for humans to drink - it’s essential for life.
Is potable water pure ?
Chemists wouldnt call it pure. Pure water only contains H2O molecules whereas potable water can contain lots of other dissolved substances
What type of water is rain water
Rain water is a type of fresh water
How can you treat fresh water sources ?
Filtration - a wire mesh screens out large twigs etc, and then gravel and sand beds filter out any other solid bits
Sterilisation - the water is sterilised to kill any harmful bacteria or microbes. This can be done by bubbling chlorine gas through it or by using ozone or ultraviolet light
What is desalination ?
Getting rid of the salt
How do you make sea water fit to drink ? Desalination
Throught distillation -
What’s a life cycle assessment ?
A LCA looks at every stage of a products life to assess the impact it would have on the environment
What are the 4 stages of LCA and explain them ?
Getting raw materials:
-extracting raw materials needed for a product can damage the local environment, e.g. mining metals
-raw materials oftwn need to be processed to extract the desired materials and this often needs large amounts of energy
Manufacturing and Packaging:
- Manufacturing products and their packaging can use a lot of energy resources and can also cause a lot of pollution, e.g. harmful fumes such as carbon monoxide or hydrogen chloride.
- You also need to think about any waste products and how to dispose of them. The chemical reactions used to make compounds from their raw materials can produce waste products. Some waste can be turned into other useful chemicals, reducing the amount that ends up polluting the environment.
Using the product:
1) The use of a product can damage the environment.
For example, burning fuels releases greenhouse gases and other harmful substances. Fertilisers can leach into streams and rivers causing damage to ecosystems.
2) How long a product is used for or how many uses it gets is also a factor - products that need lots of energy to produce but are used for ages mean less waste in the long run.
Product Disposal:
1) Products are often disposed of in landfill sites.
This takes up space and pollutes land and water, e.g. if paint washes off a product and gets into rivers.
2) Energy is used to transport waste to landfill, which causes pollutants to be released into the atmosphere.
3) Products might be incinerated (burnt), which causes air pollution.
Compare the life cycle assessments for plastic and paper bags
Raw materials for plastic bag - crude oil
Raw material for paper bag - timber
Manufacturing and packaging for plastic bag - the compounds needed to make the plastic are extracted from crude oil by fractional distillation, followed by cracking and then polymerisation. Require energy but minimal waste
Manu and packaging for paper bag - pulped timber is processed using lots of energy. Lots of waste made
Using the product plastic bag - Can be reused. Can be used for other things as well as shopping, for example bin liners
Using the product plastic bag - usually only used once
Product disposal - Recyclable but not biodegradable and will take up in landfill and pollute land
Product disposal - Biogradable, non-toxic and can be recycled
What is sustainable development ?
It is an approach to development that takes account of the needs of present society while not damaging the lives of future generations
It requires that we reduce resource use
Why are chemists important for sustainable development ?
Chemists develop new products and processes that use
less resources e.g. chemists have developed catalysts that reduce the amount of energy needed for reactions in industry.
What are the 3 Rs and what do they do ?
Reduce , reuse and recycle
Helps reduce the demand for limited resources
They help reduce the amount of waste produced
Copper is a finite resource. One way to improve its sustainability is by extracting it feom low grade ores (ores without much copper in). What are the ways of doing this ?
