Make sure you follow my STEM board on Pinterest for more ideas, and don’t forget to save the pin for later.
YC and EC love to grow things, be it plants, those odd growing toys or crystals. We have done a few crystal growing experiments over the years; we’ve made fake snow and egg geodes. This time we grew Epsom crystals. They are very different to the other types because they are really delicate and grow in a few hours.
Of course once we had started doing it we somehow ended up doing it as a potions class; YC was Hermione, EC was Draco Malfoy and I was Prof Snape. The actual prep for this activity is about 5 minutes, so it is one that can easily be done while you are getting dinner ready or have a few minutes spare.
You will need:
- Epson Salts
- A tiny bit of sand/dirt
- Food colouring
This experiment has a ratio of 1:1, so as long as you keep to that it doesn’t matter how much of the water or salt that you use. We used 1/3 cup for each of ours.
Add your Epsom salts to a bowl and then add the water. Make sure that you use hot water from the tap. You don’t want to use boiling water for this. Some people put the mixture into the microwave, but ours worked perfectly with just the hot water from the kitchen sink.
Make sure that you stir the mixture until it is all mixed in. That means you need to stir for about 2 minutes! You will probably ended up with some of the salt sitting at the bottom. This fine, basically it means that the water has become saturated and no more salt will dissolve in it.
Add a couple of drops of food colouring into your solution and give it another quick stir. We found that only some of our crystals actually took on the colour, most of them turned out clear.
Next pour your mixture into a container; we used old jam jars for this part. I have read that sometimes these mixtures don’t grow anything, to increase your chances of this experiment working add a little bit of sand/dirt/play dough to your jar. The crystals need something to initially grow on; this is called nucleation.
Place them into the freezer for 10 minutes.
After the 10 minutes are up, put the jars into the fridge. You should notice that the crystals will start to grow after a few hours, but we kept ours in there overnight.
Interestingly 3 of our jars grew very delicate crystals, whereas YC’s two grew much chunkier ones! Not quite sure how that happened, but it was pretty cool.
Both kids loved their results; EC wanted to take his out and play with them. He actually ended up putting them into his bath (they are just Epsom salts after all). YC, on the other hand, wanted to keep hers in the jars and wouldn’t let anybody touch them in case they broke.
Pin for later: