Water (Hardness of water)

CHEMISTRY  SSS2  First Term

WEEK 10

Water (Hardness of water)

Performance objectives

Students should be able to:

1. Explain the causes of hardness of water.
2. Give at least two methods employed in removing hardness of water
3. Explain methods used in purifying water.

Content

Hardness of water

What is Hard Water?

Hard water has high mineral content. It is formed when water percolates through the deposits of chalk and limestone which are made up of magnesium and calcium carbonates. It does not lather with soap, so it is not suitable for laundry purposes.

The hardness of water is harmful to the boilers as the deposition of salts occurs which reduces the efficiency of the boiler. Hard water is safe to drink but using over…