Can water rise by itself? Sometimes it seems to. Try this experiment and see.

YOU WILL NEED:
• 1 foil pie pan
• 1 cup cold water
• Food coloring
• 1 plastic two-liter bottle filled with hot tap water
• 1 ice cube
• Newspapers

DIRECTIONS:
1. Cover your work area with newspapers.

2. Pour the cold water into the pie pan, mix in four drops of food coloring, and then add the ice cube.

3. Empty the hot water from the soda bottle into the sink. (The bottle should feel warm.)

4. Stand the bottle upside down in the pan and observe.

WHAT WILL HAPPEN?
The key to this experiment is the air inside the bottle. Air expands (gets bigger) when it is heated and contracts (gets smaller) as it cools.

When you stand the warm bottle in cold water, the air inside it contracts, leaving empty space. This empty space creates a vacuum that sucks the colored water out of the pan and into the bottle.