Check out our new astronomy
project...
Click here to find
out more
Look for a tasty treat to enjoy?
What you need:
- 6 teaspoons citric acid crystals - get them from the baking
section of the supermarket or from chemists. Make sure they're
suitable for adding to food (some citric acid crystals aren't
edible).
- 3 tablespoons bicarbonate of soda
- 4 tablespoons icing sugar
- Mixing bowl
- Spoon
How to:
Ask an adult to help you find citric acid crystals.
- Mix the citric acid crystals and bicarbonate of soda.
- Bash the mixture to a fine powder with a spoon.
- Mix the icing sugar with the citric acid crystals and
bicarbonate of soda.
Try a bit of sherbet! What does it taste like? Does it feel
fizzy on your tongue?
What's happening?
When you put the sherbet on your tongue, the saliva in your
mouth causes the citric acid crystals to dissolve.
The citric acid reacts with the bicarbonate of soda and produces
carbon dioxide gas. The bubbles of carbon dioxide make the fizzy
feeling on your tongue.
Icing sugar is needed to make the mixture taste sweet and
nice.
Don't eat too much sherbet too quickly. You could end up with a
lot of carbon dioxide in your stomach, which could be
uncomfortable!
Remember to brush your teeth after eating
sweets!