Facts on Water for Kids

Water is not only the most common substance on earth, it is also one of the most unusual.
No other substance can change its shape and form like water can.

Water is made up of tiny particles called molecules. 

A single drop of water contains millions of molecules. Each of these molecules is made up of even smaller particles. These are called atoms. Each water molecule contains atoms of two substances, hydrogen and oxygen.

Two atoms of hydrogen join with one atom of oxygen to form water. 

Scientists give hydrogen the symbol H and oxygen O. These symbols are used together to give the scientific name for water—H20.
Can you see why?

Water can exist in three states—a solid, a liquid or a gas. 

The molecules that make up liquid water are always moving freely. When water is cold, the molecules slow down. If cooled enough, water can change to ice. When rain water is frozen, it takes on other forms, such as snow, hail, or sleet.
When water is heated to a boiling state, it forms steam. The molecules move around in the air with great speed and a high level of energy.
Water will always flow to the lowest place it can reach. At the Iguagu Falls, on the border of Brazil and Argentina, the waterfalls more than 231 feet (70 meters).

When water freezes, the molecules slow down and form a regular pattern. Snowflakes such as these always have six sides, though each one is different from any other.

These icicles are solid water and very hard.
As water trickles down from the eave, it freezes into an icicle. Then as more water trickles down the icicles, it freezes and adds to the size of the icicles.

This snowman contains millions of tiny ice crystals, but most of it is air.

Millions of droplets of boiling water and steam from the Old Faithful geyser, in Yellowstone National Park, come from inside the earth's crust.

The tiny droplets of water in this dawn fog in the Namib Desert, in southwestern Africa, will gradually evaporate as the day becomes hotter.