This blog post may contain affiliate links.
Friday, April 7, 2023

Fizzy Eggs: Easter Science Experiment

If your kids love fun, interactive and easy science experiments then they'll love these fizzing Easter eggs. This experiment is a fun way to combine a recipe, chemical reaction, colour mixing and sensory play all into one activity, with a fun Easter theme.

We've made fizzing pumpkins before for Halloween so this time we decided to make fizzy eggs for Easter. My girls love fizzy science experiments so much we're planning on doing lots more in the future.

baking soda fizzy Easter eggs


This fizzy Easter egg experiment is great for children of all ages from toddlers through to school kids. It's an interactive way to observe and explore chemical reactions and build fine motor skills. You'll need to prep some of the experiment the day before, but the kids can help with that too.

What is a fizzy egg?

The fizzy eggs we'll be using for this experiment technically aren't eggs at all. We're going to make them from a baking soda and water paste and turn them into eggs by putting the mixture into a silicone egg mould and freezing them. You'll need to finish the experiment to make the magic happen and turn them into actual fizzing eggs.

How to make fizzy eggs

This experiment is so simple that the kids can be involved in every single step, including the prep work {if you want them to}. If you're doing this experiment with younger children I recommend doing the prep work yourself and doing the experiment outside so the colourful mess they may make can be easily washed away.

You will need:

The beauty of this experiment is that it requires items you'll most likely already have in your pantry like bicarb {baking soda}, vinegar and food colouring. If you don't already have pipettes or plastic syringes you can get them in bulk from places like Amazon, dollar stores or some craft stores. 

We picked up our silicone egg mould for a few dollars from Riot, but you can usually find them at supermarkets, department stores, dollar stores and Spotlight in the lead up to Easter. The silicone moulds are also great to use for chocolates, jellies or making DIY crayons or chalk.

Before you start make sure you have everything you'll need and everyone has clean hands. Follow the steps to make your fizzy eggs and you can watch exactly how we did ours in the video further below. The first 4 steps are preparing the experiment and will need to be done the day or night before you plan on doing the actual experiment {steps 5 & 6}.

1. Mix baking soda {bi-carb} and water together in a bowl to make a paste. Make sure you break up any lumps in the baking soda and blend it with a spoon into a fine powder and then slowly add water and mix it together until it forms a thick paste. The amount of baking soda powder and water you'll need will depend on the size and number of moulds you're using.

mixing bicarb and water paste

2. Spoon the paste into each of the empty moulds until they're full.

spooning baking soda paste into egg moulds

3. Add a few drops of food colouring to each mould. Carefully mix the food colouring into the paste with a spoon until the paste is evenly coloured. My 5yr old helped with this step so she used a toothpick to mix it together to try and minimise mess. We used red, pink, yellow, blue and purple for our eggs, but you can use any colours you like. You can also add glitter to make them sparkly.

adding food colouring drops into egg moulds

Fizzy Egg Colouring Tips:

  • Using liquid food colouring with a squeeze top lid will make this step much easier.
  • Make primary coloured eggs to create secondary colours as they react during the experiment.

4. Place silicone mould into the freezer. To avoid the mould moving while it's in the freezer I recommend placing it on a tray. The fizzy eggs will need to freeze overnight to be firm enough for the experiment.

5. Remove frozen eggs from freezer and place onto a tray. Even though they're frozen they will be quite soft and can crumble easily so be careful when removing them from the mould.

fizzy Easter eggs on tray

6. Squirt vinegar onto the eggs with a syringe or pipettes and watch what happens. What happens to the eggs? What does the colour do? Do the eggs disappear? 

*You may want to do this part outside as it can get a bit messy if your children are like mine and start squirting the coloured water mixture around.

The girls both loved this experiment because they could do it together on the same tray, but still had their own syringes to squirt. They loved watching the eggs fizz, bubble and dissolve, and the colour ooze out, as the reaction occurred.

squirting vinegar onto fizzy eggs with a plastic syringe

Squirting the vinegar onto the eggs is a great fine motor workout for the kids as they need to suck up the vinegar and then push it back out again. It's also great for hand/eye co-ordination as they need to make sure the vinegar lands on the egg to make the reaction occur.

rainbow fizzy egg reaction

Once enough vinegar has been added to the fizzy eggs the tray will turn into a colourful fizzy lake. If you've used primary colours like us you'll also notice the secondary colours start to form as the colours combine in the water. Enjoy the pretty rainbow while it lasts though because once the kids start mixing the water around it'll soon turn to a brown mess.

Fizzy eggs baking soda science explained

Fizzy Easter eggs are a twist on a traditional bicarb and vinegar science experiment. When you squirt the vinegar onto the fizzy eggs the reaction you're witnessing as the eggs fizz, bubble and dissolve, is the same chemical reaction, however it's slightly less intense as water has been added to make the baking soda paste. Instead of an eruption of bubbles exploding out of the eggs, there's a milder bubbling fizz.

When the vinegar connects with the baking soda {bicarb} in the eggs it forms an immediate acid-base chemical reaction because the alkaline solution {the paste in the fizzy eggs} is reacting with an acidic solution {the white vinegar}. When the two solutions combine together the vinegar and baking soda convert into salt, water and carbon dioxide gas. The gas being expelled is what causes the bubbles as it escapes the liquid solution.

fizzy eggs bubbling and dissolving

fizzing Easter eggs science experiment for kids


Disclosure -  This post contains some affiliate links for your convenience, which means I may make a small commission at no cost to you, should you make a purchase.

Would you like to comment?