Question

What are the factors that cause hardness of water? How many types of hardness are there?

Answer 1

the presence of magnesium and calcium in the water

Answer 2

Permanent hardness is caused by dissolved chloride, sulphate, nitrates of Calcium and magnesium which are not removed by boiling.

There are three types of Hardness tests :-

1. Rockwell hardness test
2. Brinell hardness
3. Vickers hardness