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2.  Water on the earth:  Water is a chemical substance with the chemical formula H 2 O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bond.  Water on the earth:  Water is a chemical substance with the chemical formula H 2 O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bond.

3.  1 Water from the sea evaporates.  2 Water vapour rises,cools and condenses. Clouds form.  3 Wind moves the clouds.  4 Condensed vapour falls as precipitacion: rain, snow or hail.  5 Some water infiltrates into the sea.  6 Groundwater goes into the sea.  7 River water goes into the sea and other rivers.

4. Water is always moving and changing its physical state.

5.  Salt water: Is found in oceans and seas. It represents more tha 97% of the total water on earth.  Fresh water: Is found in rivers, lakes, glaciers, groundwater and at the poles. It represents less than 3% of all the water on our planet.

6. The amazon river release so much water into the sea that the sea is fresh water near the mouth of the amazon. It’s the most abundant river in the world.

7.  The Nile is the largest river in the world. It’s 6.756 km long, it runs of ten countries.

8.  The Pacific Ocean is the largest of the Earth's oceanic divisions. At 165.2 million square kilometres (64.1 million square miles) in area, this largest division of the World Ocean – and, in turn, the hydrosphere – covers about 46% of the Earth's water surface and about one- third of its total surface area.

9.  The Arctic Ocean, located in the Northern Hemisphere and mostly in the Arctic north polar region, is the smallest and shallowest of the world's five major oceanic divisions.

10.  A glacier is a largest persistent body of ice that forms where the accumulation of snow exceeds over many years.

11. Glaciers form where the accumulation of snow and ice exceeds ablation. As the snow and ice thicken, they reach a point where they begin to move, due to a combination of the surface slope and the pressure of the overlying snow and ice.

12.  tsunami is a series of water waves caused by the displacement of a large volume of a body of water, typically an ocean or a large lake. earthquakes, volcanic eruptions and other underwater explosions (including detonations of underwater nuclear devices), landslides, glacier calvings, meteorite impacts and other disturbances above or below water all have the potential to generate a tsunami.

14.  Javier Viñuelas Ferrando  Pablo Rodríguez Lancho.  Javier Trujillo Rodríguez.