Flashcards
Water Purity
Cards in this deck (13)
- 1why is water important industrially, and how much of fresh water in UK is used in the industry?its important, as a cheap raw material, coolant and a solvent
between 2/3 of all fresh water in the UK goes into industry - 2in the UK we get out water from? (2)1. SURFACE WATER: lakes, rivers and reservoirs > these sources start to run dry in the summer months
2. GROUNDWATER: aquifers (rocks that trap water underground) - 3how could these water resources be limited?depending on annual rainfall
demand for water increases every year - 4what is the 3 step process of purification?FILTRATION
SEDIMENTATION
CHLORINATION - 5explain the first step of purification?FILTRATION >>>
a wire mesh screen out of large twigs etc... and then gravel and sand beds filter out any other solid bits - 6explain the second step of purificationSEDIMENTATION
iron sulphate or aluminium sulphate is aded to the watter, which makes fine particles clump together and settle at the bottom - 7explain the third step of purificationchlorine gas is bubbled through to kill harmful bacteria and other microbes
- 8what can't be filtered out of the water,what do these include and what can these cause?some soluble impurities that are dissolved in the water are not removed, because they can't be filtered out, these include minerals with could cause water hardness handsome harmful/poisonous chemicals such as pesticides or fertilisers
- 9what are three things that can cause low levels of pollutants which are still found after purification1. Nitrate residues
2. Lead compounds
3. Pesticide residues - 10where do NITATE RESIDUES come from, what problems can it cause?from excess fertiliser 'run-off' into rivers/lakes if too many nitrates get into drinking water it can cause serious health problems, especially for young babies . Nitrates prevent the blood from carrying oxygen
- 11where do LEAD COMPOUNDS come from, can it cause any health problems is so what are they?old lead pipes
lead is v. poisonous particularly to children - 12where can PESTICIDE RESIDUES come from?from spraying too near to rivers and lakes
- 13what are the cons of distillation- distillation needs loads of energy
- because of this it's very expensive
- not practical for producing large quantities of fresh water
Information
- Description
- GCSE Chemistry (C4) Flashcards on Water Purity , created by Lily Pritchard on 26/04/2016.
- Created by
- Lily Pritchard
- Views
- 0
- Rating
More on Water Purification and Treatment