Water and Humans go hand in hand!!!

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Water and Humans go hand in hand!!!
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Importance of Water to human life

• Next to oxygen, water is the most essential
  element to human life the body usually cannot
  survive longer than several days without water (a
  maximum of 1 week).
• Water is essential to the functioning of every
  single cell and organ system in the human body.
• Water makes up greater than 2/3 of the weight of
  the human body the brain is 75 water, blood is
  83 water, bones are 22 water, muscles are 75
  water, and the lungs are 90 water.
• Africa and some parts of India do not have
  treated water supplies
• This causes many harmful diseases and unnecessary
  problems.

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How is water treated?

• The process of the treatment of drinking water
  can be divided into four main parts
• Screening
• Clarification
• Filtration (to remove larger particles)
• Disinfection

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Hard and Soft waters

• Hard
• Does not easily form a lather with soap
• Contains Calcium Compounds
• Contains Magnesium Compounds
• Contains Iron Compounds
• Can be found in places such as London, Lincoln
  and Bristol.

• Soft
• Forms a lather easily
• No Calcium Compounds
• No Magnesium Compounds
• No Iron Compounds
• Can be found in places such as Swansea, Leeds and
  Cardiff.

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Advantages and Disadvantages of Hard and Soft
Water

• Hard
• Advantages
• Calcium ions in the water are good for childrens
  teeth and bones.
• Hard water is used in the brewing of beer
  because of the taste dissolved salts give to the
  beer.
• Disadvantages
• Soap is wasted, as it does not work effectively
  with this water type.
• Hard water tastes unpleasant in comparison to
  soft water.

• Soft
• Advantages
• Forms a lather easily with soap
• Tastes pleasant
• Disadvantages
• Does not have extra minerals as Hard water does
• Therefore does not decrease numbers of chances of
  heart disease

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How can temporarily hard water and permanent hard
water be softened?

• Temporarily Hard water
• Boil the water!!
• Boiling water is only an effective method of
  softening small volumes of water. It is time
  consuming and expensive for large quantities.

• Permanently Hard water
• Cannot be reversed by boiling the water so there
  are two other methods
• Using washing soda!
• Using an Ion exchange column!

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Softening Temporary Hard Water
This is caused by calcium or magnesium
hydrogen-carbonate. It can be removed by boiling
the water. Calcium hydrogen carbonate calcium
carbonate water carbon dioxide. This
reaction is the opposite of when hard water
forms. Boiling water is only effective when
softening small amounts of water. It is time
consuming and expensive for larger qualities.
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Using Washing soda

• Substance added to washing water to soften hard
  water. The calcium and magnesium ions in hard
  water react with the carbonate ions from the
  sodium carbonate and a precipitate of calcium
  carbonate results.
• Na2CO3(aq) CaSO4(aq) CaCO3(s) Na2SO4(aq)
• In the above process, the scale thats formed is
  easily removed because it is insoluble. The
  Na2So4 (aq) that has formed dissolves and so the
  hardness has been removed.

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Using an Ion exchange column

• http//www.yenka.com/freecontent/attachment.action
  ?quickv2att2226
• Hard water passes through a column containing a
  suitable resin in small granules. The column
  contains an excess of sodium ions. When the hard
  water passes through the column, the Ca2 ions in
  the water are exchanged for Na concentrated
  solution of sodium chloride through the column.
  Na ions do not cause hardness and so the water
  is soft. Domestic water softeners work on this
  principal.

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