Hardness of Water - Study Material
Definition:
Hardness of water refers to the presence of dissolved salts of calcium (Ca) and magnesium (Mg) in water.
These salts interfere with the lathering property of soap and lead to scale formation in boilers and utensils.
Types of Hardness:
1. Temporary Hardness
- Caused by bicarbonates of calcium and magnesium.
- Removed by boiling the water.
Reaction: Ca(HCO3)2 --> CaCO3 + CO2 + H2O
2. Permanent Hardness
- Caused by chlorides, nitrates, and sulfates of calcium and magnesium.
- Cannot be removed by boiling.
- Requires chemical treatment for removal.
Disadvantages of Hard Water:
- Wastes soap due to formation of insoluble scum.
- Forms scale in boilers, reducing efficiency.
- Causes damage to utensils and plumbing.
- Unsuitable for laboratory and industrial purposes.
Definition:
Hardness of water refers to the presence of dissolved salts of calcium (Ca) and magnesium (Mg) in water.
These salts interfere with the lathering property of soap and lead to scale formation in boilers and utensils.
Types of Hardness:
1. Temporary Hardness
- Caused by bicarbonates of calcium and magnesium.
- Removed by boiling the water.
Reaction: Ca(HCO3)2 --> CaCO3 + CO2 + H2O
2. Permanent Hardness
- Caused by chlorides, nitrates, and sulfates of calcium and magnesium.
- Cannot be removed by boiling.
- Requires chemical treatment for removal.
Disadvantages of Hard Water:
- Wastes soap due to formation of insoluble scum.
- Forms scale in boilers, reducing efficiency.
- Causes damage to utensils and plumbing.
- Unsuitable for laboratory and industrial purposes.
