DISADVANTAGES OF HARD WATER

 

Hardness is the characteristic of water which does not give good lather with soap. This property of water is due to the presence of bicarbonates, chlorides and sulphates of calcium, magnesium and other salts.





Some important disadvantages of hard water are the following:

Hard water is not useful for various domestic purposes, viz washing, bathing, drinking, etc. The ions responsible for the hardness convert soluble soaps to insoluble precipitates. This causes wastage of soap in washing and bathing. Also, presence of iron salts may result in staining of cloth.

Hard water is harmful for many industries such as textile, sugar, paper, laundry, etc. Dissolved calcium, magnesium and iron salts may react and affect the following properties:

  • May cause coloured spots on fabrics in textile industry. 
  • May cause difficulties in the crystallisation of sugar in sugar industry.
  • May cause wastage of lot of soap in laundry.
  • Giving a smooth and glossy finish to paper in paper industry. 
  • Hard water is also not suitable in steam generation in boilers since there arise many troubles like scales and sludge formation, corrosion, priming and foaming and caustic embrittlement.
  • Hard water is not suitable in laboratory analysis also because the hardness-producing ions interfere in various reactions.

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