Water is unique as it is the only substance that naturally occurs on Earth as a solid, liquid, and gas. It is composed of hydrogen and oxygen, the two most common elements in the universe. Around 75% of the Earth's surface and a human body is made up of water, as water molecules cycle between bodies of water, ice, and vapor over periods of years.

1. Water: a special substance

2. Ice Water Steam Water is the only substance that occurs on the earth in all 3 states.

3. H, He and O are the 3 most common elements in the universe.

4. The earth‘s surface is covered 70-75% with water.

5. The human body is made up of about 75% water.

6. In the course of 100 years a single water molecule spends about 98 years in the sea.

7. 18 months as ice

8. 2 weeks in rivers or lakes

9. Less than a week in the atmosphere