Q. Consider the following chemicals:
1. Copper sulfate
2. Ozone
3. Hydrogen peroxide
4. Fluoride
Which of the above are used in chemical treatment process of drinking water?

Explanation by: Chandani

Copper sulphate is used as an algicide for algal growth is copper sulfate. Ozone or Hydrogen peroxide is added to oxidise organic compounds, and thus reduce the amount of coagulant required. Fluoride is a naturally occurring mineral in water and many foods. In addition, fluoride is intentionally added to the public water supplies, because it has been demonstrated that communities with fluoride added to their water supplies have significantly reduced incidence of tooth decay in children. Fluoride makes teeth more resistant to the acid formed by bacteria in the mouth by preventing these acids from removing essential minerals from the tooth surface. Fluoride also helps to repair damaged tooth enamel.