The formula for water is H 2 O, meaning there are two hydrogen atoms for each oxygen atom. This joining up of atoms is very lucky. Without it there would be no planets , no life , no people . They can do things which separate atoms never could. They will play a special part in our story.
Water molecules are sticky.
Click here to find out why . Water will play a key role in this story because it has some extraordinary properties. Liquid water expands when it freezes. Water molecules are sticky . This stickiness gave shape to proteins .