Welcome to chemical reactions Fun Science home kit! Thank you so much for your support. We hope that you enjoy these experiments as much as we do. In your kit you should have:
  • Citric acid
  • Bicarbonate of soda
  • Test tube
  • Balloon
  • Pipette
  • 2 x Sandwich bags
You will need:
  • A bottle (500ml is best)
  • Water
Blowing Up a Balloon
  • Fill your bottle ¼-½ full with water 
  • Add 1 teaspoon of citric acid 
  • Put the lid on the bottle and shake until the citric acid has dissolved 
  • OPTIONAL: you could also add some vinegar if you want even more fizz!
  • Put 1 tsp bicarbonate of soda into the balloon. You may need to use a funnel or have someone help you! 
  • Put the neck of the balloon over the neck of the bottle. 
  • Lift up the balloon so the bicarbonate of soda falls into the bottle.
  • Watch the video at the end to find out why this happens! 

Exploding sandwich bag

  • Mix 2tsp of citric acid into 500ml water and pour into one of the sandwich bags
  • In the other sandwich bag, put 3 tsp of bicarbonate of soda. 
  • Carefully place the bag of citric acid and water into the bag of bicarbonate of soda, making sure this bag sits on top of the powder. Do not seal the inner bag.
  • Seal the outer bag (you might want to ask a grown up to make sure it is completely sealed) and take it outside or do the next part in the sink or in a tray. 
  • Tip the bag back and forth so that the water starts to mix with the bicarbonate of soda.
  • When it starts to expand (blow up) place it on the floor/in the sink/in the tray and step back! 
  • Watch the video at the end to find out why this happens! 

Popping Test Tube

  • Take the lid off your test tube
  • Add ½ tsp citric acid
  • Then add ½ tsp bicarbonate of soda
  • Add 1 pipette of water and quickly put the lid on. Make sure you don’t hold it under your face just in case it pops before you are ready. 
  • Hold it in front of you with your arm stretched right out. 
  • If it doesn’t pop straight away, keep your arm stretched out and shake the test tube gently. 
  • If you are quick enough, put the lid back on and see if it will pop again! 
  • Watch the video at the end to find out why this happens! 
Safety – Never aim the test tube at anyone. Don’t hold in under your face or look directly over it. If it doesn’t pop after 30 seconds, ask a grown up to remove the lid and try again.  Now lets go back to Chemical Cress and find out the science behind these experiments – Enjoyed this kit? Visit our shop for more science kits

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