10 STEM experiments that go fizz!

We’ve had lots of fun with “potions” experiments.

But to be honest they have been a bit random.

So I’ve been making lists of different groups of potions experiments that build on each other and give us more chance to explore the connections between different phenomena we observe.

This week I am sharing a list of 10 STEM experiments that go fizz!

1. Blowing bubbles through a straw

OK this isn’t an experiment, but it’s hard for young children to make sense of what a gas is as they can’t see or feel it.

But they can feel what breath is in their body and so blowing their breath out into water and seeing the water bubble is a great introduction to the idea that there are amazing, invisible gases in the air that can make things go fizz, bang pop!

Not Just Cute

2. Classic volcano explosion

This classic where you add baking/bicarb of soda to vinegar and food colouring and see it “erupt” is a great experiment to start with or to repeat as it is the foundation for all sorts of experiment.  

The acidic vinegar and alkaline soda together form fizzy carbon dioxide.

If you’ve not done it before Preschool Alphabet has some nice simple instructions.  

You can make it more volcano like by building the experiment jar into a play dough or even snow mountain and even more exciting by adding sparkles or glitter to the mix!

Not Just Cute has a nice version where you hide different food colouring in different jars beneath the baking soda all ready for the vinegar to be added so you get different coloured eruptions.

3. Creating a bigger “explosion”

After you’ve made a basic “volcano”,  Mini Eco shows how you can explore making it even more explosive (and foamy) by adding dish washing liquid to the vinegar and food colouring.

4. Controlling the explosion

Once you’ve made a bigger explosion, it’s a good opportunity to talk about whether you can keep the explosion under control and stop it from getting bigger and bigger and exploding all over the kitchen!

 Life with Moore Babies has a good example of how to do this by putting oil into the vinegar and dish washing liquid.

Juggling with Kids

5. Blowing up a balloon with the explosion

Now you’ve got those explosions under control, it’s great to see how you can actually use the gas generated from the experiment by blowing up a balloon with it.

 This is another classic experiment and there’s loads of versions around, but I really like this one from Juggling with Kids

6. What else can blow up a balloon?

Having inflated the balloon, you could see whether there is anything else in the kitchen that has got “magic gas” in it and set up a controlled experiment of different bottles of liquid – including some fizzy soda which will work!.

7. Making the balloon bigger

Gas from warmer liquid should inflate the balloon more.  Happiest Mom on the Blog has got a controlled experiment that will allow children to discover the impact of temperature on the power of the gas.

8.  Even more foam

Obviously, young children don’t need to worry about the names of chemicals but you can introduce them to the idea that different chemicals have different effects.

Preschool Powol Packets shows how you can generate serious amounts of foam by combining dish washing liquid with hydrogen peroxide, yeast and a very small amount of water.  The yeast activates the break down of they hydrogen peroxide into oxygen which causes all the bubbles.
 

9. The biggest explosion yet

The exploding geyser of mentos and cola is another experiment that you will almost certainly have seen before – Mommas Fun World has a simple introduction if you haven’t.

But it can also be a good foundation for your own freestyle experiments to explain what is happening .

We’ve seen that fizzy drinks release enough gas to blow up a balloon but will all fizzy drinks create such a big explosion or is there something in the cola?

You can then experiment with different types of sweets – do all sweets react or even all mint sweets or is there something special about the minty mentos?

10. Lava Lamp

My final fizz experiment is yet another old fave – the lava lamp.

Growing a Jewelled Rose has a lovely example of them made from oil, soda water, Alka Seltzer, food colouring and sparkles.

You can experiment with making them fizzier by adding in more Alka Seltzer.

They’re lovely to look at and play with in there own right but they also provide a great link to next week’s list of experiments about solutions because they illustrate how the oil and soda water stay separate from each other and the food colouring behaves differently in the oil than from the soda.

We’ve had so much fun with these experiments … do hope you enjoy them too. 

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