what is the hardness of water in an area which contains limestone?

Answer 1

Because limestone (calcium carbonate) dissolves so well in water it is a common factor in hard water.

The value of hardness depends on the amount of time (the biggest factor) the water was in contact with the limestone.

Here is a table that shows hardness values:

Soft: 0 - 20 mg/L as calcium
Moderately soft: 20 - 40 mg/L as calcium
Slightly hard: 40 - 60 mg/L as calcium
Moderately hard: 60 - 80 mg/L as calcium
Hard: 80 - 120 mg/L as calcium
Very Hard: >120 mg/L as calcium

Get an "A".

Answer 2

It depends on the length of time the water has been in contact with the limestone.