Activity Title: Water Bottle Fountain
- School Age
What Do I Need?
- Empty water bottle
- blu-tac (or similar)
- tray for catching the water (optional. You could always do it outside, in a bath, or near a sink)
How Do I do It?
- Begin by blowing up a balloon and asking your child "What is in the balloon?"
- Let the balloon go and talk about what happens.
- Take the empty water bottle and ask your child "What is in the bottle?"
- Blow up the balloon again and place the mouth of the balloon over the empty bottle without letting too much air escape. Ask your child, "Why isn't the balloon going down?"
- Now, to make the water bottle fountain
- Carefully, with a pen, poke a hole in the empty bottle just big enough for a straw to poke through and seal with blue tac. (This is the hardest part of the activity and is best done by an adult. If the bottle is wet, the blu-tac will be hard to stick)
- Ask your child, "What do you think will happen if we pour water in?"
- Pour water into the bottle over the level of the hole.
(NOTE: Make sure that your straw is pointing up, and that you fill the water so that it's level with the very top of the straw.. this is because water will level itself out so anything above the top of the straw will probably come out)
- Plug any leaks that you have by squishing down the blu-tac. At this point with the water at the same level as the top of the straw, it will not come out.
- Blow up the balloon, hold it closed and put the mouth over the top of the bottle. Let go, and wheeeeeeeeeeeeeeeee! a fabulous fountain!
What's the Science Behind It?
This experiment allows children to see that air takes up room and is always present even though we can't see it. When you blow up a balloon with air and let go of the top, the air escapes and the balloon goes flat. However, when the balloon is placed over the bottle, the air doesn’t escape because the bottle is full of air so the air inside the balloon has no where to escape. With the bottle filled with water, the air in the balloon pushed down on the water and forced the water up the straw.