I *think* I may be chocolated out. I think. But to the right of me right now I have half of an eaten (or is it uneaten? Hmmm?) Baileys Easter egg. I had half of it at about 2pm and promptly fell into a chocolate induced coma. I woke at 4.30pm to be greeted with rebels who had not been listening to their grandmother. Cue mean mummy and tantrums. I am certain that I was not the only one wishing I stayed asleep!!
You may have gathered from the above that I have over eaten and my kids are running wild. Yep, we are being indulged at Grandma’s house. And there has still been time for a little science. This time something quick and simple and using things from MIL’s kitchen. Remember, my aim is to do science with preschoolers with inexpensive and easily available resources so there is little excuse to not give this a go.
Science at this time of year HAD to involve eggs. There were plenty eggsperiments I contemplated over but I settled to wow the kids with a ‘bouncy’ egg investigation. For this you need: an egg, vinegar, a glass and food colouring (this is optional). This investigation does take some time – needs to be set up roughly 2-3 days in advance. Perfect for the Easter holiday – set up, eat chocolate and hang out with the family whilst you wait.
Of course to begin, discuss the egg. I asked the kids where the egg came from, what it should become and why the egg had not hatched. An list of the questions asked can be found at the bottom of this article. I ended the questioning asking about the shell and what happens to the shell if the egg was dropped/hit/fell.
I then set up the experiment.
To set this up simply fill the cup/container with vinegar (enough to completely cover the egg) and place the egg in. You can add food colouring in if you wish – just to make it a bit more of a sensory experience for the kids. It is just as cool without colouring. Once you place the egg in, you will see a reaction immediately. The kids observed and we discussed what we saw. I spoke about a gas being produced and my eldest remembered about the vinegar and balloon experiment. The few investigations we have done so far have linked nicely. We have worked with vinegar, talked about CO2 and gravity and so the kids have been able to build and deepen on their knowledge further in this investigation.
And that is it. Leave for 2-3 days and keep checking on it and you shall see the shell dissolve. Keep discussing observations and referring to their predictions. Just a note – you may want to keep the container covered to avoid the smell of a fish and chip shop in your home. It will overpower the chocolate. We can not have that over Easter.
On the 3rd day we fished the egg out of the vinegar and the kids were wowed. We took a raw egg and the egg that had been soaking in vinegar and a few plates to do the next step. It was going to be messy so we took this outside. With the young ones I thought it important that we compared the egg with a raw egg so they could really experience the difference. We dropped the raw egg, observed and discussed. This was then repeated with the vinegar soaked egg and lo and behold, the kids witnessed a bouncy egg! I did not manage to get a good shot of the bounce, but give it a go for yourself to see!
They enjoyed poking it and I think were pretty freaked out by it!
My youngest then decided to have a go at bouncing and did so with FORCE so you can imagine what happened next! Yep…..
So as a note, to get a few bounces out of it – bounce gently and not from too great a height. However, this would again be another great experiment: bouncing from different heights, on different surfaces etc. If you would like some suggestions/further ideas then feel free to get in contact.
The science bit:
Vinegar is an acid, a weak acid but an acid nonetheless. The egg is made of calcium carbonate and when the two combine a chemical reaction occurs – a salt, water and carbon dioxide is made. The co2 is what causes the bubbling which is what you see as soon as the egg is in the vinegar. Over time the reaction continues causing the shell to break down and dissolve. As you observe over day 2 & 3 and lift the egg out of the vinegar you will see that you are able to practically rub the shell off. The egg is still raw inside, it is protected by its membrane. This is that clear film you see inside an eggshell. If you choose to break a raw egg at the same time as bouncing the egg you will find this handy as you can take the raw egg’s shell and point out that membrane. Why is it so strong? That membrane is made of strong stuff, like keratin and collagen, the same protein found in human hair and skin. It is incredibly strong which explains why the egg can bounce.
What is an egg?
Where does this egg come from?
What other animals lay eggs?
What is inside the egg?
What is on the outside?
What can the egg become?
What does it need to hatch?
What will the vinegar do to the egg?
What is making the bubbles?
What can you see is happening?
There are a lot of interesting investigations that you can do with eggs – even ones that will challenge the idea that the eggshell is fragile.
Give this eggsperiment a go, it is a great way to get started and will certainly wow!
Now, where is that Baileys egg……ooohh….wait, hot cross buns…..