While working on the potions it became clear that erupting and exploding reactions were the ones that the children sought the most. After a quick browse on Pinterest we came across Elephant’s Toothpaste. How could we resist?
We used hydrogen peroxide as part of this experiment which is obviously nasty on the skin so some time was spent discussing ways of ensuring we were safe. This is always part of our process but was especially focussed on for this experiment.
We were careful to keep our hands away from the bottles –
“It’s dangerous! Don’t touch! But we can watch.”
“Don’t touch! It would burn your skin!”
The hydrogen peroxide was mixed with a little washing up liquid and food colouring, grown ups needed to do that bit. The experiment used yeast as well which we could touch and so help with that.
We mixed the yeast in a beaker first.
It was smelly!
We all took turns to mix.
We watched closely as Ailie carefully poured the chemicals together.
Then we poured the mixtures together….
We had a range of different predictions. Alfie thought the yeast would turn green. Millie predicted it would go bubbly. Jack thought it would turn into water. Everyone else just thought the colour would change. However no-one predicted quite what happened.
“It Exploded!!” – Alfie
It foamed up and over the top and kept growing.
The peroxide and yeast have an exothermic reaction (it releases heat) which burns all the peroxide away leaving hydrogen and oxygen which with the washing up liquid means it turns into harmless foam. The reaction continues until all the yeast or the peroxide is gone so the foam keeps growing.
Or as Ramsay put it…
There was a bottle and it went over the bottle and made a volcano!
Here are our volcanic eruptions:
Scott was impressed.
We made different clours
We remembered to be careful.
We watched the different reactions
Some seemed to go on for longer and make more foam.
We carefully touched the foam – it was warm!
When they slowed right down the, Ailie took the dangerous bottles away.
So then we were left with coloured foam. Hmmmm what could we do with that? Well we had to play and explore the texture and colours of course!
We all got stuck in.
“It’s soft!” “It’s warm!”
“It’s gooey!” “It’s slimy!”
We were fascinated with the mixing colours.
The afternoon children were more tentative.
“It’s nice!”
“I’m getting the blue!”
“Let’s mix them up”
After a while it all turned pink and slimy.
We found we could draw patterns and marks in it.
Aaron drew himself!
It was great for early writing patterns.
Eventually the mixture got a little too runny. But it was fun to make a huge circle pattern by running around and around the tough spot. There was only one way to make it better….
Make more!
The instructions for elephants toothpaste can be found on Pinterest. The hydrogen peroxide can be bought at Sally’s and the yeast can be bought at any supermarket in the baking section.
Please remember that anti bacterial washing up liquid is NOT to be used in the experiment. Cheap bubble bath can be substituted instead.
Why not have a go yourself? Don’t forget to share how you get on in our comments.
it became clear that erupting and exploding reactions were the ones that the children sought the most. After a quick browse on Pinterest we came across Elephant’s Toothpaste. How could we resist?
(it releases heat) which burns all the peroxide away leaving hydrogen and oxygen which with the washing up liquid means it turns into harmless foam. The reaction continues until all the yeast or the peroxide is gone so the foam keeps growing.
