To compile a flow diagram of the WHOLE water treatment process. Your task: To compile a flow diagram of the WHOLE water treatment process. THIS SHOULD APPEAR IN ALL YOUR BOOKS! EACH PERSON has an allocated area to review: a) Sedimentation b) Filtration c) Chlorination EACH PERSON should answer these questions about their SECTION and be ready to SHARE them. 1) What does it do to the water? 2) Which chemicals are involved? 3) Which stage in the process is it? Students are divided into groups of 4, each is given a topic: Sedimentation Filtration Disinfection Fluoridation They are compile a water treatment process together by taking notes on their given topic using the video and by collecting information from the allocated sheets. This should take the form of a flow diagram and should be in all their books. As a group they should then evaluate the ads and disads of adding chlorine and fluoride to water. I can explain the processes used to treat water 1

1) What does it do to the water? a) Sedimentation 1) What does it do to the water? Removes solid matter, creates floc which is formed when the small particles of dirt clump together to make smaller ones, they then sink to the bottom of the tank and as sludge and are then removed. 2) Which chemicals are involved? Aluminium sulfate, lime 3) Which stage in the process is it? The second stage after large debris such as leaves and twigs are removed by screens. 2

1) What does it do to the water? b) Filtration 1) What does it do to the water? Filters out remaining small particles of mud and grit, pesticides and other organic impurities 2) Which chemicals are involved? Activated carbon, fine sand 3) Which stage in the process is it? The third stage after sedimentation. 3

1) What does it do to the water? c) Chlorination 1) What does it do to the water? Removes microorganisms including viruses, bacteria and fungus 2) Which chemicals are involved? Chlorine gas, ozone 3) Which stage in the process is it? The final stage before the water is pumped through pipes to houses. State one advantage and one disadvantage of adding chlorine to water.... I can evaluate some advantages and disadvantages of softening water and adding chlorine and fluorine to it (A/B) 4

The water treatment plant I can explain the processes used to treat water The water treatment plant 5

Reflection Activity bacteria filtration chlorine calcium ions Make an explanatory sentence by choosing a pair of words from below and linking them together. (use as much chemistry as you can) Do this twice! dissolved gases bacteria filtration chlorine calcium ions microorganisms water