The Importance of Water

1
The Importance of Water
2
Water The Facts

• Water is possibly the most important compound in
  living organisms.
• Water consists of 1 atom of oxygen combined with
  2 atoms of hydrogen.
• Water makes up 70 to 95 percent of most organisms.

3
What are the characteristics of water?

1. Water is polar.
2. Water molecules attract other water molecules.
   This property is cohesion.
3. Water displays adhesion.
4. Water expands when it freezes.

4
Water is Polar

• A polar molecule has an unequal distribution of
  charge-each molecule has a positive end and a
  negative end.
• All polar substances are attracted to other polar
  substances.

5
Why is this polarity important?

• Polar water molecules attract other water
  molecules as well as ions and other polar
  molecules.
• Because of this attraction, water can dissolve
  many ionic compounds, such as salt and polar
  molecules like sugar.

6
How do water molecules attract?

• Water molecules form hydrogen bonds.
• Hydrogen bonds are weak bonds that form between
  the positively charged hydrogen atoms of one
  water molecule and the negatively charged oxygen
  atoms of another water molecule.
• This ability of water molecules to stick together
  is called cohesion.

7
Also due to its polarity

• Water displays the property of adhesion which is
  the ability of one substance to cling to another.
• Examples of adhesion include waters ability to
  creep up thin tubes. Plants show this property
  when they send water from the soil up through
  their tissues.

8
And finallywater expands when it freezes.

• Because of this property, ice is less dense than
  liquid water.
• This property can be seen when ice forms and
  floats on the surface of a pond.

9
Water to drink

• 66 of the human body is made up of water.
• At just 2 dehydration your performance decreases
  by around 20.
• We should drink at least 1½ litres of water a day.

10
Water Diseases

• 80 of all illness in developing countries is
  caused by water related diseases.
• 90 of wastewater in developing countries is
  discharged directly into rivers and streams
  without treatment.

11
Water World

• Two thirds of our planet is covered by water.
• 97.5 of the water is saltwater.
• The majority of freshwater is beyond our reach,
  locked into polar snow and ice.

12
Clean Water

• The number of people with access to clean water
  has doubled in the last 20 years.
• 1.1 billion people in the world still do not have
  access to safe water. This is nearly 20 of the
  population.

13
World Water Uses
14
Saving Water

• Do you leave the tap on when you clean your
  teeth? You waste 5 litres of water.
• You only need ¼ litre!

15
Bath or Shower Water?

• An average bath uses 80 litres of water.
• An average shower only uses 35 litres.

16
Water Future

• The UN estimates that by 2025, 75 of the world
  population wont have reliable, clean water.