Question

If total hardness of water is 380 ppm and non-carbonated hardness 300ppm, then permanent hardness of water is​

Answer 1

p106 mL of water contains 200 g calcium carbonate.

103 mL of water contains 0.200 g calcium carbonate.

This corresponds to 1000.200=0.002 mol calcium carbonate.

Hence, the concentration of calcium carbonate is 0.002M.

Answer 2

The permanent hardness of water is​ the non-carbonated hardness is $300ppm$

Explanation:

Given the total hardness of water are 380 ppm

and non-carbonated hardness 300ppm

Non-carbonated hardness is the permanent hardness

Hardness is that property by which lathering of soap does not take place. It is due to the calcium and magnesium salts.

There are two types of hardness

1. Carbonate hardness or temporary hardness

- The hardness is caused by the carbonate salts of calcium and magnesium e.gcalcium carbonate, calcium bicarbonate, magnesium carbonate and magnesium bicarbonate

2. Non-carbonate hardness or Permanent hardness-It is the hardness that is caused by sulfates, chlorides, and nitrates of calcium and magnesium. e.g calcium sulfate, magnesium sulfate, calcium chloride, magnesium chloride, etc.

Here in the given question, the non-carbonated hardness is the permanent hardness that is $300ppm$

Total hardness =Temporary hardness +permanent hardness.