Blowing Up Balloons with Co2

Chemical Reaction with Balloons


Chemical reactions make for some great experiments. Make use of the carbon dioxide given off by a baking soda and lemon juice reaction by funnelling the gas through a soft drink bottle and in to your awaiting balloon!


Our aim is to create a chemical reaction that will make carbon dioxide, which we will use to blow up a balloon.


  • Balloon
  • About 40 ml of water (a cup is about 250 ml so you don't need much)
  • Soft drink bottle
  • Drinking straw
  • Juice from a lemon
  • 1 teaspoon of baking soda


  1. Before you begin, make sure that you stretch out the balloon to make it as easy as possible to inflate.
  2. Pour the 40 ml of water into the soft drink bottle.
  3. Add the teaspoon of baking soda and stir it around with the straw until it has dissolved.
  4. Pour the lemon juice in and quickly put the stretched balloon over the mouth of the bottle.


We predict that the balloon will inflate because of a chemical reaction between the bicarbonate soda and the lemon.
Big image


-When the lemon juice hit the bicarbonate soda water the mixture started to fizz and bubble.

-This released gases that blew up the balloon .

-Because our bottle was big the gases spread out so less went into our balloon.


It would have have been better if our bottle had been smaller, the gases would of gotten more faster to the ballon. We know this because some people also did this experiment but with smaller bottles and their tries were more successful.

Our results mostly supported our hypotheses. It was mostly right because the balloon did inflate, but not completely.