This is an exciting experiment that you can try at home. Experiment by creating your own crystals- why not try and create lots of different coloured crystals and create your own crystal garden. Check out this post for details on how to create fun crystals.
For this experiment you will need Epsom salt, glass jars, liquid water colours, water, a bowl or measuring cup, a fork and a microwave.
First of all you will need to add some of the salt to the jar (you will need an equal amount of water so keep a note of your measurements). It is essential that you get the ratios correct in order for the experiment to work. If you are using larger jars you may wish to increase the ratio to get a better result.
The next step is to heat up the water- about 250ml or an equal amount of salt that you used in step 1 (you can use the microwave for this part or alternatively use a stove or heated water from a kettle).
You then need to add the liquid water colours to the water and stir so that is mixed in equally.
Mix together the water mixture into the jar so that it combines with the salt. This needs to be done quickly when the water is still warm.
Stir the salt and water for 1-2 minutes to dissolve the salt. Don’t worry if some of the salt remains undissolved at the bottom of the jar.
Next you need to place the jar right at the back of your fridge. You may wish to cool the mixture first in the freezer for 10 minutes and then place it in the fridge. This will increase the chances of creating crystals, but will increase the time to complete the experiment.
Then you will need to be really patient as you will need to leave the mixture overnight. This allows growing time- you will be amazed by the results when you wake up!
You will need to poor out any excess liquid (there maybe some left at the bottom of the jar).
Next you need to use a wet paper towel to wipe away any excess salt and colour near the top of the jar.
You now have a complete crystal garden- look through the side of the glass to see f you can see the crystals.
Why not experiment with different colours?
Does the ratios of salt and water change the shape of the crystals?
Why not get a magnifying glass and look at your crystals more closely. You may want to touch the crystals- be careful as they are going to be quite delicate.
The Science Bit:
The process of crystal forming is called crystallization. Crystals often form in nature when liquids cool and start to harden. Certain molecules in the liquid gather together as they attempt to become stable. They do this in a uniform and repeating pattern that forms the crystal.
In nature, crystals can form when liquid rock, called magma, cools. If it cools slowly, then crystals may form. Many valuable crystals such as diamonds, rubies, and emeralds form this way.
Another way crystals form is when water evaporates from a mixture. Salt crystals often form as salt water evaporates.