What you need:
- icing sugar
- sodium bicarbonate (baking soda)
- citric acid powder (in the supermarket baking section)
- plastic cups
What to do:
- Mix together:
– 1 tablespoon icing sugar
– 1 teaspoon baking soda
– 1 teaspoon citric acid
- Lick your lollipop.
- Dip your wet lollipop into the mixture and lick the lollipop again.
- Feel what’s happening on your tongue.
- Dip again (or eat the sherbet with a spoon)!
- Experiment with different amounts of the ingredients,but be careful of having too much citric acid or it will taste very sour.
The dry ingredients are dissolving in the saliva in your mouth and then reacting with one another. You might remember from high school chemistry that:
acid + carbonate –> carbon dioxide + salt + water
C6H8O7 + 3NaHCO3 –> 3CO2 + Na3C6H5O7 + 3H2O
And that’s the reaction happening here.
The fizzing you can feel is tiny bubbles of CO2 being produced and popping on your wet tongue.