water

The basic needs of every being and most important thing in life is known as water.  Water is a liquid at ambient  conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state, water vapor or steam. Its molecular formula is H₂O because its molecule contains one oxygen and two hydrogen atoms connected by covalent bond. 
   Water covers 70.9% of Earth's surface and is vital for all known forms of life. It is mostly found in oceans and seas. 97% of water is taken by oceans, 2.4% polar ice-caps and 0.6% is taken by ponds rivers and lakes. It moves through a cycle called evaporation. In this process water is evaporate and goes up by the help of sun light and form cloud, after cloud is cooled it comes down in the form of rain. This is called water cycle. 
    Water is used in different purpose like drinking, cooking, washing, bathing, etc. Water is involved in our daily work directly or indirectly. Without water our life is impossible and we cannot even imagine our life without water. Waters also help in making electricity by the help of hydro electricity projects.