A better way to blow up balloons

A better way to blow up balloons
Children’s Corner

Chemical reactions make for some great experiments. There is nothing wrong with conducting experiments which do not seem to have any immediate practical, real world benefit. However, sometimes we discover things that can make our lives just a bit easier. Perhaps you are tired of blowing up balloons before a party (hopefully there will be a return to lively parties in future as more people are vaccinated).

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 an awaiting balloon.

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

– Before you begin, make sure that you stretch out the balloon to make it as easy as possible to inflate.

– Pour the 40ml of water into an average sized bottle.

– Add the teaspoon of baking soda and stir it around with the straw until it has dissolved.

– Pour the lemon juice in and quickly put the stretched balloon over the mouth of the bottle.

If all goes well, your balloon should begin to inflate. Adding the lemon juice to the baking soda creates a chemical reaction. The baking soda is a base, while the lemon juice is an acid, when the two combine they create carbon dioxide (CO2). The gas rises up and escapes through the soft drink bottle, it doesn’t however escape the balloon, pushing it outwards and blowing it up. If you don’t have any lemons then you can substitute the lemon juice for vinegar.

This is a great way of giving your lungs a rest while you prepare for your upcoming celebrations.

Does changing the amount of baking soda and lemon juice change the size of the balloon when it inflates? What would happen if you used another acid, like vinegar, instead of the lemon juice? Would it react the same with the baking soda?

Science is all about discovery and if people never asked questions, we certainly wouldn’t have all the technology we are so used to in the modern world. Sometimes it can be a simple question like, do I really have to blow up all these balloons with nothing but my lungs? Some readers may smugly say they have no need of such an experiment as they have a pump, but where is the fun in that!