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Over the last few days we have been doing quite a few activities using balloons. I haven’t posted them all yet but they will be coming up over the next couple of weeks, so please keep checking back.
There are literally hundreds of ways to play with bicarbonate of soda and vinegar. Over the years we have used it to make volcanoes, magic potions, and foaming sensory play. Now we are using it to help inflate a balloon.
You will need:
- Bicarbonate of soda
- Used plastic bottle
- Safety goggles (optional)
I’ve put the safety goggles as optional, but with younger children I would highly encourage them to wear them, because if the balloon pops or comes loose, you won’t want to get an eye full of vinegar.
Start pouring some vinegar into the plastic bottle. We didn’t use measurements; we just went with what looked a good amount.
Next place the funnel into the balloon and add the bicarbonate of soda into it.
Then place the opening of the balloon round the mouth of the bottle. Lift the balloon, so that all the contents fall into the bottle.
As the bicarbonate of soda and vinegar react the balloon will start to inflate.
Once the vinegar has stopped fizzing, take the balloon off and tie off the end.
Both YC and EC really loved doing this; they experimented with just how much vinegar or bicarbonate of soda to use. They tried to predict if the balloon would end up being bigger or smaller.
The did discover that the balloon felt heavier than a normal balloon and was harder to get it to bounce around than a balloon filled with air.
The Science Behind It
When the bicarbonate of soda (which is a base) and vinegar (acid) mix, you get an acid based reaction. The base and acid react with each other; they partially break apart and form different substances. This is called neutralisation because the end product is neither a base nor an acid. In this case you get water, salt, and carbon dioxide. The CO2 expands inside the bottle and balloon, causing the latter to expand. As CO2 is heavier than the surrounding air the balloon sinks.
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