Water & Water Pollution -

Chemical Test For Water -

1. Cobalt (II) Chloride = Blue to Pink
   1. CoCl2 (s) + 6H2O (l)  <=>  CoCl2.6H2O (s)
2. Anhydrous Copper (II) Sulfate = White to Blue
   1. CuSO4 (s) + 5H2O (l) <=> CuSO4.5H2O (s)

Purity Tests -

1. Specific boiling point = Pure
   1. Distilled water = Purest water, hence it is used in chemistry
2. Range of boiling point = Impure

Natural Water Contains -

1. Dissolved oxygen — Beneficial for aquatic life
2. Metal compounds — Provide essential minerals BUT some are toxic
3. Plastics — Harm aquatic life
4. Sewage — Contains harmful microbes [Disease]
5. Harmful microbes
6. Nitrates and Phosphates from fertilizers — Deoxygenation and Aquatic life damage

Water Treatment -

STEP 1 - Remove Insolubles -

1. Sedimentation