Slides in this set

Slide 1

Slide 2

Preview of page 2

· Only small % of water on Earth is drinkable
· Water is continually circulated by the water
cycle ­ driven by energy from the sun
· Water can be purified in 2 ways, that are?
· Drinking water sources need to be away from
possible pollution problems ­ like what?…read more

Slide 3

Preview of page 3

Water Cycle…read more

Slide 4

Preview of page 4

Obtaining Drinking Water
· Water is filtered (large pieces removed)
· Filter beds ­ sand and activated charcoal.
The charcoal improves taste and removes
unpleasant odours
· Finally disinfected with Chlorine ­ removes
bacteria, viruses, protozoa and
cryptosporidia…read more

Slide 5

Preview of page 5

· Some countries distil seawater ­ as
long as they have plenty of fuel
available cheaply because it takes a
lot of energy!!
· Seawater is heated, only the pure
water is evaporated and then
condensed and collected…read more

Slide 6

Preview of page 6

· Adding fluorine to water is called
· Improved dental health by decreasing
tooth decay
· Too much fluorine can leave teeth
mottled and stained
· Scientists believe benefits out way
risks but some human rights groups
disagree!!…read more


No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »