Balloon inflator #2

Balloon inflator #2

Objective

To use the gas from a soda bottle to inflate a balloon

Difficulty:

Time: a few minutes

Adult supervision: minimal

Dangers: none

Materials

1.5 L bottle of soda (unopened)

Balloon

Instructions

Pre-stretch the balloon by inflating and deflating
Open the bottle of soda and place the end of the balloon over the opening of the bottle
Wait and see how long it takes for the balloon to start to inflate

The Science

The substance that makes fizzy drinks effervescent (that's another word for fizzy) is carbon dioxide. It is added to the soda under pressure. When the pressure is released, carbon dioxide gas starts to separate and we can see it as bubbles.

Further investigation

You could try using different sized bottles of soda. Does a soda bottle twice the size result in a balloon twice the size? Gee, older kids, you could get really technical here and try to work out the volumes.