This simple kitchen science experiment is a tasty way to learn about chemical reactions…

What you need:

• 1 teaspoon citric acid

• 2 tablespoons icing sugar

• 3 tablespoons jelly crystals
  (choose a flavour that you love!)

• 1 teaspoon baking soda

• Optional cellophane bags

• Optional cardboard straws

• Tape

What to do…

1. Add all of the ingredients to a small bowl.

2. Stir the ingredients until combined ensuring any clumps are broken up.

3. Taste a little of the sherbet and modify the recipe to taste.
   Citric acid is very sour (it’s what gives lemons and other citrus fruits their sour taste). If your sherbert is too sour try adding a little more icing sugar.

4. Spoon your sherbet into a cellophane bag.

5. Cut a straw in half and insert in to the open top of the cellophane bag.

6. Pinch the open end of the bag around the straw and secure it with tape, to stop the sherbet spilling out.

7. Enjoy the sherbet by sucking it through the straw!

The science in your sherbet

Sherbet fizzes on your tongue because of the combination of citric acid and baking soda.

Citric acid is an acid, while baking soda is part of another group of chemicals called bases.

When you mix the base and acid together, it causes a chemical reaction. In this reaction, the molecules of the starting chemicals break apart and reform into new chemicals (known as products).

In this case, the new chemicals formed are water, sodium citrate (a type of salt) and carbon dioxide gas - this gas escapes as tiny bubbles.

You can’t see all of this happening, but the bubbles of gas give us the fizz on our tounges.

You’ll observe that the chemical reaction doesn’t happen as soon as the ingredients are mixed. In powder form, the chemicals can’t mix together. BUT, when we add water or saliva (also known as a catalyst) the citric acid and baking soda molecules dissolve and can find each other more easily… causing the reaction.

The icing sugar and jelly crystals in our recipe are just there to make the chemical reaction taste yummy!

Did you give it a go?

Send us a photo of your homemade sherbet and what you learnt and you might find your creation featured on the Upstart website OR in a future issue of Upstart magazine… AND win a prize!