17 Claremont Bradford West Yorkshire BD7 1BG

British Science Week Competition: Colour Changing Drink Experiment

Posted by ACAP
Being stuck at home for the past few months, we’re sure you’re missing being in the school science lab. So to celebrate British Science Week 2021 we’re inviting you to turn your kitchen into your very own lab! For a chance to win a free science kit, see if you can turn a regular drink into something spectacular. Recreate this experiment and record your results by Friday 14th March to be entered into the competition.

Here’s what you’ll need:

  • Red cabbage
  • Bowls
  • Boiling water (ask a grown up to get this for you)
  • A sieve
  • Clear jug
  • Teaspoon
  • Bicarbonate of soda
  • Clear glasses
  • Lemonade


  1. Rip up some red cabbage leaves into small pieces and put them into a bowl
  2. Ask a grown-up to pour some boiling water onto the cabbage leaves so they’re covered. Leave it to cool for 20 minutes
  3. Drain off the cabbage juice by pouring it through a sieve into another bowl
  4. Next, put the cabbage juice into a clear jug and stir in a level teaspoon of bicarbonate of soda – this should make the liquid a bright blue colour! (if it looks more purple than blue, add a bit more bicarbonate of soda and stir it again)
  5. Finally, place the jug in the fridge for 40 minutes
  6. Now, fill a clear glass with some lemonade about half way and top it up with a small amount of your bicarbonate of soda mixture from the fridge and watch it turn into a pinky-purple fizzy drink!

The science behind it: The cabbage has a special pigment in it (an anthocyanin) that changes colour depending on how acid or alkaline something is. Bicarbonate of soda makes the mixture alkaline – and blue – but the acidity in the lemon-based drink turns it pink. Pretty clever, right?

Send us a clip of your finished experiment to office@acap.org.uk by Friday 14th March for a chance to win a free science kit!

Related Posts



Pin It on Pinterest

Share This