Science in the Park - Balloon Science

Today's Science in the Park features balloons!  Since it is HOT out here - we are using some regular balloons to inspire conversation and some water balloons to cool off!

Material List:

• baking soda
• vinegar
• balloons
• empty water bottles
• cooler full of water balloons
• straws
• scissors
• tape
• yarn/string
• liquids that smell (ex. mouthwash, vanilla extract, etc)

Experiment 1: Smell the Balloon

Preparation: squeeze a little bit of a strong-smelling liquid into a balloon and then blow the balloon up.  We decided to use bubblegum mouthwash, vanilla extract, and lemon soap.

Action!  The kids took turns guessing what was in each balloon. 

The Science: Balloons are made of a porous material that allows the scents to escape.

Experiment 2: Blow up a Balloon

Preparation: Give each child a water bottle. 

Action! Spoon 3 teaspoons of baking soda into the bottle.  Then add about a 1/2 cup of vinegar quickly.  As it starts to fizz - slide the balloon on top of the water bottle so that the escaping gas fills up the balloon.

The Science: The vinegar (acid) neutralizes the baking soda (base) resulting in water and carbon dioxide.  It is the carbon dioxide gas that blows up the balloon.

Experiment 3: What floats?

Preparation: Give each child a tray of about an inch or two of water in it and a water balloon.

Action! Use the air filled balloon from the previous experiment and the water balloon and see which one floats.

The Science: The water balloon sinks while the air-filled balloon floats.  It's a simple observation but it reinforces that the water balloon is heavier than the air filled balloon and that is why it sank.

Experiment 4: Crazy Balloons

Preparation: Squeeze a water balloon into a deflated regular balloon.  Then blow up the regular balloon and tie it off.

Action! Gently throw the balloon and watch it move around like crazy!  Careful - they pop easily!

The Science: The center of gravity of the air filled balloon is in motion because of the water balloon inside moving around.

Break for a water balloon fight!

Experiment 5: Balloon Rockets

Preparation: Blow up a balloon and tape it to a straw.  Then feed a string through the straw so that the straw with the balloon on it can easily glide along the string.  Add a clothespin to the balloons knot for weight.  Tie something (we used leaves found on the ground) to either end of the string so that the straw/balloon cannot slide off.

Action! Fly the rocket!  Start it at the top of the play structures or stand on top of the picnic tables.  Talk about how to make it go faster! 

The Science: This science is physics.  Put the string at a steep angle and notice how it goes faster than at a small slant.