C3-Hardness of water

Soft water
1. Makes a nice lather with soap
  1. No scum or scale
    1. Cheaper - however no known health benefits
Hard water
1. Scum occurs when adding soap
  1. Calcium and magnesium ions make the water hard
    1. Reacts with soap to make scum which is insoluable
      1. Need more soap to get a lather - more expensive
        When heated, hard water forms scale (CaCO3) on the insides of pipes/kettles.
        This reduces the efficiency and may need to be replaced. This can block pipes.
        Rain falling on rocks such as limestone/chalk can dissolve compounds like MgSO4 (it is soluable)
        Goof for teeth and bones and less risk of hear disease.
Temporary hard water - Softened by heating. Caused by hydrogencarbonate ions
1. Permanent hard water - Can only be softened by removing/replacing calcium/magnesium ions
  1. Caused by dissolved calcium sulfate.

Resource summary

	Created by Lily O'Brien about 7 years ago