Sherbet

Materials

2 tablespoons icing sugar

1/4 teaspoon bicarbonate of soda (baking soda)

1/4 teaspoon citric acid (found in baking section of the supermarket)

optional: 1 teaspoon jelly crystals (to give more flavour)

spoon for mixing

bowl

Difficulty:

Time: a few minutes

Adult supervision: minimal

Dangers: none

Instructions

Put the icing sugar, baking soda and citric acid (and jelly crystals if using) in the bowl
Mix well with a spoon
Eat!
If you have sherbet left over, store in an airtight container or zip lock bag.

The Science

What happens when you put the sherbet in your mouth? The fizzing sensation is caused by the water in your saliva reacting with the citric acid (an acid) and baking soda (an alkali). Carbon dioxide is produced from this reaction which causes the fizzing sensation.

Further investigation

What happens when you vary the ratio of the ingredients?
Put some sherbet in a glass of water and watch the reaction