Pour bicarb soda into container, carefully mix in a few drops of food colouring at a time with a spoon until you get the desired colour. The mixture should be crumbly, and holds its shape when pressed with the spoon. If not, add a few drops of water and mix, repeat until it does.
Fill the muffin tray or ice cube tray with the mixture, about 2/3 of the way up. Pack down with the back of the spoon.
Leave to dry for an hour then turn out onto a plate.
Drip vinegar on top of the fizzy bomb or chuck one into a cup of vinegar!
Bicarb soda and vinegar fizzy bombs!
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What is the chemical reaction occurring here?
Vinegar + Bicarbonate Soda ---> Carbonic Acid + Sodium Acetate
The carbonic acid is unstable though, so it breaks down into water and carbon dioxide forming the bubbles you see when the bicarb soda comes in contact with vinegar.
For more bicarb soda and vinegar experiments, check out this list in our blog!
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