I wrote this experiment for my children’s school Family Science Night (more on that at a later date) but it would work really well at a summer fete too, perhaps charging 50 pence a go!

What You Need (per person)

• Plastic cup
• Plastic spoon

What To Do:

Mix the following in your cup:

• 1-2 heaped teaspoons icing sugar
• 1/4 – 1/2 teaspoon bicarbonate of soda
• 1/4 – 1/2 teaspoon citric acid
• Enjoy with your liquorice stick!

What’s Happening:

The sugar is there to make the sherbet taste sweet.

The citric acid is there to make it taste tart and also to create the fizzy reaction along with the bicarbonate of soda.

When the citric acid and bicarbonate of soda dissolve in the saliva on your tongue, they begin to react and create the fizzy sensation.

Citric Acid + Bicarbonate of Soda à Sodium Citrate + Water + Carbon Dioxide

It is the carbon dioxide that gives the fizz, forming bubbles directly on your tongue!

P.S. Citric Acid can be difficult to find, I get mine from the local ironmongers within their winemaking section.

Next Time: Fun with Egg in a Bottle…