This cool Borax crystal making science experiment will teach your child about solutions and crystallization while also making a neat decoration: Their name in crystals.
You can hang your Borax crystals in a window to add a sparkle to any room!
What is Chromatography?
Chromatography separates components from mixtures. Each component has a unique separation rate which can be used to identify different components in a mixture.
By using chromatography, we can find out all the different components a mixture is made of.
This method was discovered by Mikhali Tsvet, who separated colour pigments of plants!
The experiment below uses the method of chromatography. Let’s dive in!
Exploring STEM Concepts in Crystal Making
Here are some key concepts related to the process of crystal-making that will be helpful to understand before you conduct your experiment.
Solution
A solution is a type of homogenous mixture of two or compounds. Homogenous means that we cannot see the individual compounds or substances in the mixture.
Solubility
Solubility describes a substance’s ability to dissolve another substance.
Solvent
A solvent is a liquid that is able to dissolve another substance. The solvent in your experiment is water.
Solute
A solute is a compound that can be dissolved into another substance. The solute in your experiment is Borax.
Materials for Borax Crystals
- Pipe cleaners
- Fishing line or yarn
- Pencils or wooden skewers
- Scissors
- Glasses or plastic containers (one for every colour you use) (must fit 3 cups of water)
- Borax
- Water
- Food colouring
- Measuring cup
- Tablespoon
- Paper towel
- Paper
- Pencil
How to Make Borax Crystals
Step 1
Fold and bend the pipe cleaners to spell your name.
Make sure it fits into your container without touching the edges.
Younger children completing this experiment can explore creating each letter one by one.
Older children can be challenged to create their name in cursive by connecting the pipe cleaners.
Step 2
Suspend your pipe cleaner letters from a pencil or skewer.
If you would like to colour each letter differently they will all need to be suspended on different pencils or skewers. Use the fishing line or yarn to do this.
Make sure that the pipe cleaner sits a couple inches down from the pencil or skewer.
Step 3
Set out as many containers as individual pipe cleaner letters you created in step 1. Next we need to make a saturated solution of Borax and water.
Step 4
Mix each solution until the Borax is completely dissolved.
STEM Q for You: Why do you think the recipe requires hot water? What do you think would happen if we used cold water and why? … Solubility increases with temperature, meaning that the water can dissolve more Borax when it is hot than when it is cold.
Step 5
Add a couple drops of food colouring to each solution you have made and stir.
Step 6
Time to add the letters! Lower them into each container. Rest the skewer or pencil that the pipe cleaner is attached to across the top of the cup or container. Make sure the letters are not touching any part of the container, they should be completely suspended.
STEM Q for You: Why do you think it’s important that the pipe cleaner letters don’t touch any part of the container? What do you think the end result would be if it did?
Step 7
Make a prediction! What do you think is going to happen when you leave your pipe cleaner letters in your saturated solution overnight?
Leave the solutions in a safe spot overnight. Make sure to take observations every few hours if you can but do not touch! You should also notice a lot of crystal build up. It will fall to the bottom over time.
Check in on your “crystal” every few hours. Observe and log what you see. What is changing? Why do you think this is happening?
Step 8
The next day you should be ready to see your crystal creations! Pull the pipe cleaners out and set them aside on a paper towel to dry off. Once they are dried, use the fishing line or yarn to tie them in front of a window! Watch the sparkle they emit!
Refer back to your logs. Compare what your predictions were to the actual outcome. What was the same? What was different? Why do you think this was the outcome?
Mixture vs. Solution
What is the difference between a mixture and a solution? What is an example of each?
A mixture is a combination of two or more compounds mixed together. There are two types of mixtures, heterogenous (meaning that you can see the separate compounds) or homogenous (meaning that you cannot see the different compounds).
A liquid homogeneous mixture is called a solution.
An example of a heterogenous mixture could be rocks and sand.
An example of a solution could be salt dissolved into water.
How Do Borax Crystals Form?
In this activity, as the temperature of the water cools back down, the solubility of the water decreases, meaning that the solution becomes less saturated with Borax.
As this happens, the Borax begins to crystallize with whatever surface it comes in contact with.
The crystals continue to build on top of each other and that’s why the crystals form so thick on the pipe cleaners!
