2.12 Potable water

Question 1

Potable water

Answer 1

It is suitable for drinking so it must have:
Low levels of microbes
Low levels of contaminating substances
It is safe but not the same as pure water

Question 2

Making waste and ground water potable

Answer 2

There are three stages that need to take place for waste water to be potable:
Sedimentation: large insoluble particles will sink to the bottom of the water
Filtration: Water is filtered through beds of sand which removes small insoluble particles
Chlorination: Chlorine gas is put through water to kill microbes

Question 3

Making sea water potable using distillation

Answer 3

You filter the seawater and then boil it, meaning that water vapour would cool and condense before being collected in a tube.

Question 4

Water in analysis

Answer 4

It must be pure because any salts could react with the substances you are analysing, which could end up in a false result.