The water is a component of our nature that has been present on Earth for more than 4500 million years, occupying three quarters of the planet´s surface.

At temperature and pressure, both the oxygen and hydrogen have the form of gases out when they join to form the water takes form of a liquid that is transparent to light, no taste, odor or color (in a state of purity).

Water is the only compound that can be in three possible satates of nature:

• in liquid form: in rivers, lakes, seas and oceans.
  
• in gaseus form: part of the Earth´s atmosphere as water vapor.
  
• in solid form: in the form of snow or ice, as in the polar cpas on mountain tops and in places on Earth where the temperature is below zero degrees Celsius.
  

However, if the position of the Earth was closer or more distant whit respect to the position of the Sun, the coexistence of the three states in this compound would be much less likely.

The density of water is 1g/cm³ and its molecular structure is:

— Carolina Pérez Muñoz