A Fizzy Surprise

The kids and I are great fans of the simple baking soda and vinegar reaction. They come back to this one regularly. It’s so easy and versatile. This week I changed it up a little bit by adding in a little surprise.

Normally when you mix baking soda and vinegar it fizzes and obviously remains white. We have added colour before, like when we are making a ‘volcano’, but the kids add it with me. Today, I added the food colouring without them knowing and I added different colours too so that each time they poured the vinegar on the baking soda a different colour appeared.

For this experiment we used:

– food colouring

– baking soda

– vinegar

– a cupcake tray

We did our experiment on quite a big scale but you could easily scale it down if you didn’t have a lot of food colouring, baking soda or vinegar!

Firstly, I set up the experiment without the kids seeing. I put a few drops of food colouring in the bottom of each cupcake holder.

I then covered the food colouring in baking soda. As the weather was good I placed the tray outside and called the kids over. I told them we would do the vinegar and baking soda experiment but there was a surprise this time.

They took it in turns to spray the vinegar at each pile of baking soda and they were delighted to see the different colours appear. They started guessing what each next colour would be as they went.

We found the liquid food colouring worked better than the gel food colouring. We also found some colours worked more quickly than others – green was particularly good.

This little activity works really well with my friend Karen’s Sunday School lesson for this week. It’s all about Jesus appearing to two friends on the road to Emmaus. They didn’t recognise him until later on and they were really surprised! You can read the story and download the resources here.