Using Resources Flashcards
Examples of natural products that are supplemented or replaced by agricultural and synthetic products
Rubber is a natural product extracted from sap of trees however man made polymers have been made which can replace rubber in uses such as tyres.
Agriculture can develop conditions for natural resources (increase their crop yield) for food , timber , clothing or fuel
Distinguish between finite and renewable resources
Renewable: reform at a similar rate to, or faster than , we use them (timber , fresh water and food)
Finite- aren’t formed as quickly enough to be replaceable (minerals , fossil duels , nuclear fuels)
Distinguish between potable and pure water
Potable water is water that has been treated and safe for human consumption
Pure water only contains h2O molecules unlike potable water which contains many dissolved substances
Describe treatment in ground water and salty water
Ground water is collected by aquifers undergound. Water is filtered using a wire mesh and sand with gravel to screen debris out of the water and then is sterilised to kill off microbes (ozone,chlorine, uv)
Distillation is used to make salty water potable. Firstly test the water with universal indicator add acid or alkali until neutral. Then heat up a round bottmed flash with the water until the water starts to evaporate and steams enters the condenser which turns into a liquid into a beaker (wait until all water is boiled). Finally, retest the purified water with the PH meter and check if neutral (reverse osmosis can also be used membrane only allows water to pass through)
Give reasons for why water is treated
Prevent pollution and keep up access to water:
We use water for lots of things during our domestic lives which could be seen as wasteful.
Agricultrual systems also produce a lot of waste water (nutrient run-off and slurry)- toxic to the environement
Industrial processes produce lot of waste water with chemicals needs to be treated before released to protect environemnt and people
Required practical 8: analysis and purificstion of water samples from different sources, including pH , dissolved solids and distillation
1)Add drops of universal indicator solution and compare the colour of the water sample to the PH chart
2)Weigh a clean watch glass on a balance
3)Add 5cm^3 of a water sample on the watchglass and evaporate it then measure (salt left)
4)Distill the water sample to obtain no dissolved solids
5)Add a few drops of universal indicatie to the distillate
6)Test the distillate by placing it ontop of a watchglass and boiling it until no presence of liquid then measure the watchglass on the balance. If it is the same then no dissolved solids is present in the water sample
How is potable water obtained from waste, ground and salt water
Potable water is gained through ground water by collecting it in an aquifer then screening it with a wire mesh and gravel/sand to remove debris and screened to kill microbes with (chlorine , uv , ozone)
Watse water can be turned potable through sedimentation. Heavy solids sinks at the bottom and form a sludge which is removed and broken down in a seperate tank using bacteria whereas the lighter effulent at the top is treated using biological aerobic dgestion (break down organic matter)
Potable water is obtained from salt water through distillation which requires testing the sample boiling then condensing and finally re-tetsing to find if the sample is neutral.
Give examples of alternative biological methods of metal extraction
Copper ore is becoming more scarce and new ways of extracting copper from low- grade ores include phytomining and bioleaching.
Phytomining- uses plants to absorb metal compounds. The plants are harvested and then burned to produce ash that contain metal compounds.
Bioleaching- uses bacteria to produce leachate solution that contain metal compound, that can be processes to obtain certain metals by displacing using scrap iron or electrolysis
Carry out a simple comparitive LCA for a shopping bag made of plastic and paper
Plastic bag ~~~~ paper bag:
Raw materials: crude oil ~~~~ timber
Manufacturing and packaging: compounds extracted needed from crude oil by fractional distillation followed by fracking and polymerisation (little waste)
~~~~~
Pulped timber processed using lots of energy (lot of waste)
Using the product: Re-usable/multipurpose ~~~ one use
Product disposal: Recycleable but not biodegradeable ~~~~ biodegradeable and non toxic and recycleable
Evaluate ways of reducing the use of limited resources
Mining and extracting metals is a lengthy and energy costly process we shoukd stop this and research other ways.
Reycling metals (melting and casting) uses much less energy needed to mine and extract new metal, cut down water and conserves finite amount
Glass bottled can be re-used without reshaping
Glass can be recycled (melted and reshaped) for other long term uses
