Balloon in a Bottle

(WETM-TV)

Adult Supervision

2 Soda Bottle Clear (2 liter size)

Balloons

Hot Glue Gun

Carpenter Knife

Hand Saw

Marker

Procedure

1. Push an un-inflated balloon through the opening of the soda bottles mouth.  Fold the balloons openings around the mouth of the bottle. 

2. Once in-place blow into the balloon and see if the balloon expands to fill the capacity of the soda bottle. 

What Happened?

The balloon did expand to fill the bottle!  Too much air is already filling up the space within the bottle.  As you continue to blow into the balloon there is no room for the balloon to expand within the bottle.

How can you make the balloon expand? 

Adults you will not want your kids to do this portion of the project.       

Using a hand saw cut off the opening of one of the 2 liter bottles at the bottles neck, be sure to make the cut as straight and clean as possible.  Once finished sawing one of the bottles trace an outline of the cut-off piece’s neck at the lower end of your other bottle. Carefully cut out a hole with a carpenter’s knife within your balloon bottle.  Be sure to take extra care NOT to cut yourself.   Hot glue gun the sawed piece into the opening you just cut, with the sawed piece’s cap still in place.  Allow a few hours for the glue to dry. 

Once the glue has dried re-try the experiment.  Place a balloon in the newly constructed bottles mouth, wrapping the balloon out around the sides.  Unscrew the cap from the piece you recently glued down at the lower end of the bottle.  Blow into the balloon!  Watch as the balloon expands.  Before removing your mouth from the bottles end screw the cap back onto the lower end of the bottle.  As you back away from the bottle you will notice that it does not deflate.  Try tying off the inflated balloon.  Now you have a balloon in a bottle.

What Happened?

During your second attempt at the experiment the newly constructed valve allowed for air to escape from the bottle.  This left room for the balloon to expand.