Lesson 12: Water for drinking Flashcards
1
Q
What is distillation?
A
- Distillation is a separating technique used to separate two liquids or a solvent from a solution. Useful for producing pure water from sea water.
2
Q
What is the name of the liquid that is collected at the end of distillation?
A
The liquid collected at the end of distillation is the “distillate.”
3
Q
Name the apparatus in which a gas turns into a liquid during distillation.
A
The apparatus where a gas —> liquid is known as a “condenser.”
4
Q
What is the boiling point of water?
A
100 °C
5
Q
In order for a mixture of two liquids to be separated, what must be different?
A
- Their boiling points must be different for them to separate.
6
Q
What are the 3 main steps of distillation?
A
- ) Heat and evaporate
- ) Cool and condense
- ) Collect distillate
7
Q
What is pure water?
A
- Made up of 100% water, nothing added.
8
Q
What is potable water?
A
- Contains mineral ions( impurities) but is safe to drink.
9
Q
What are the 5 steps of making water safe to drink?
A
- ) Screen: removes large objects (leaves and twigs.)
- ) Coarse Filter: remove small objects
- ) Sedementation tank: sand and oil settle
- ) Fine filter
- ) Sterilisation (ozone, UV light, Chlorine)
10
Q
What can be used to sterilise water?
A
- Ozone
- UV light
- Chlorine
11
Q
What is reverse osmosis?
A
- Water passed through partially permeable membrane under high pressure.
- Pores allow water only and no ions.
12
Q
What are the disadvanatges of reverse osmosis?
A
- Requires expensive membranes
- produces large volume of waste water
13
Q
What are the disadvanatges of distillation?
A
- requires a lot of energy to boil water
- Requires energy to cool steam down (by particles colliding to release energy –> turn to liquid)
- Waste is very salty+ harms marine organisms
