Question

Water is considered 'hard' if its hardness is of
the order of​

Answer 1

Answer:

Measures of water hardness

General guidelines for classification of waters are: 0 to 60 mg/L (milligrams per liter) as calcium carbonate is classified as soft; 61 to 120 mg/L as moderately hard; 121 to 180 mg/L as hard; and more than 180 mg/L as very hard.

Answer 2

Water is considered 'hard' if its hardness is of

Water is considered 'hard' if its hardness is ofthe order of 200 mg/l (acceptable limit) or 600mg/l (permissible limit).

• These acceptable and permissible limit is fixed by the Bureau of Indian Standards (BIS).
• The hardness of water is associated with things like the scaling of pipes.
• Dissolved calcium and, to a lesser extent, magnesium cause hardness in water.
• In the lab water analysts test hardness by the titration method and for evaluating total hardness of water they use EDTA and Hardness Buffer.