Topic C10- Using Resources Flashcards
(7 cards)
What is potable water?
Water that has been treated or naturally safe for humans to drink
How can filtration and sterilisation be used to treat water?
Filtration- a wire mesh screens out large twigs. Then gravel and sand beds filter out any other solid bits
Sterilisation- bacteria and microbes are killed by bubbling chlorine gas through it or by using ozone or ultraviolet light
What are the four steps of distillation to purify water?
1) First, neutralise the water by adding some acid or some alkali until the pH is 7
2) Heat up the water so it evaporates and enters the condenser as steam. The condenser will cause the steam to condense due to the cold water around it.
3) Retest the pH using a pH meter to check it’s neutral.
4) Once the water’s been distilled you can check if there are any crystals in the round bottom flask, to tell whether there were salts
What is bioleaching?
Bacteria are used to convert copper compounds in the ore into soluble copper compounds.
What is phytomining?
Growing plants in soil that contains copper.
What are the four stages of the life cycle assessment?
Getting the raw materials
Manufacture and packaging
Using the product
Product disposal
What are the 5 stages for sewage treatment?
1) Sewage is screened- this involves removing any large bits of material and grit
2) In a settlement tank it undergoes sedimentation- heavier sink to bottom, lighter effluent floats
3) The effluent is removed and treated by biological aerobic digestion- when air is pumped through the water to encourage aerobic bacteria to break down any organic matter
4) The sludge gets broken down by bacteria by anaerobic digestion- which breaks down the organic matter. The methane gas can be used as an energy source and the remaining digested waste can be used as an fertiliser.
5) Water containing toxic substances should use chemicals or UV radiation
