“Dad! Dad! Where are you?” Bernie shouts running through the house.
“I’m out here, Bernie,” Mr. Reynolds says from the garden.
Bernie goes outside carrying a bag in his hand. His father looks up at him from where he sits thinning the carrots. “What’s that you’ve got, Bernie?”
“It’s a magic trick. Do you want me to show you?”
Do you want to do Bernie’s magic trick with him?
Here’s what you need:
- A glass bottle
- A balloon
- Baking soda (bicarbonate of soda)
Bernie pours some vinegar in the bottle.
Now Bernie’s dad holds the balloon open so that Bernie can put the baking soda inside. He puts about one tablespoon.
Now they put the balloon over the mouth of the bottle being careful not to let the baking soda fall inside the bottle.
Then they tip the balloon up and let the baking soda fall into the vinegar.
Wow!! What happened?
Did you see what was happening in the bottle when the baking soda mixed with the vinegar? What happened?
That was a lot of fun, but Bernie has to go now!
See you next time!!!
Bernie’s magic balloon is not magic at all. It’s a chemical reaction between the vinegar (acetic acid) and the baking soda (bicarbonate of soda) that releases carbon dioxide. Whenever you combine an acid with a carbonate carbon dioxide is released. The released carbon dioxide blows up the balloon because it is trapped in the bottle and needs to escape.
Here’s the chemical equation:
The fact that baking soda releases carbon dioxide is very helpful. In cooking we add baking soda to cakes and other baked goods to get them to rise. The dough rises because of trapped carbon dioxide. If you look carefully at a cake or bread made with baking soda, you will see little holes or pockets; those pockets were made by trapped carbon dioxide. The carbon dioxide is released when the baking soda is heated. Or alternatively we can use baking powder, which is a mixture of bicarbonate of soda and tartaric acid. So once again we have the acid carbonate chemical reaction to get carbon dioxide just like in Bernie’s magic balloon.