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Science

Chemical economics

How pure is our water? - Test

1.

Which of these is NOT an important source for the public water supply in the UK?

2.

Which of these washes off farmland and pollutes the water supply?

3.

A sample of water is treated with silver nitrate solution and a cream precipitate is seen. What does this indicate?

4.

Which of these processes is NOT commonly used in the UK to treat the water supply?

5.

Chlorine is used to treat the water supply because:

6.

Which reagent is used to test water for the presence of sulfate ions?