Put the lid on the bottle and shake until the citric acid has dissolved
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
Pour 300ml water into the sandwich bag.
Add 3tsp citric acid. Close the bag in case it spills.
Take the toilet paper and place it on a dry surface. It is best to use 3 sheets of poor quality toilet roll. Kitchen roll can be too thick!
Put 3tsp of bicarb in the middle
Fold both edges to the middle
Fold the top down and the bottom up!
Fold the edges in again. You now have your powder pack! Careful not to rip the paper!
Get a grown up to unzip the bag a little. Pop in the powder pack and get the grown up to zip the bag up quickly, shake and throw the bag on the ground. Stand back! The bag will fill up with carbon dioxide gas, expand and hopefully explode!!!
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 – http://https://www.youtube.com/watch?v=hZ2-nYl5YSEEnjoyed this kit? Visit our shop for more weekly science kits
