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If you want a fun and easy science experiment for kids, try growing borax crystals on pipe cleaners. This beautiful experiment forms large crystals in just a few hours, or overnight. Plus, kids love it. Today I am updating an old favorite of ours.
Borax powder is a laundry cleaning product. You’ll find it at the grocery store with the laundry detergents. It is a toxic chemical so make sure you do the pouring with it and wash hands after touching it. They should be safe to hold and play with once completed, as long as kids do not ingest it!
Here is a shot of the first time we tried it a few years back. We did a lot of different shapes.
You can make some amazing crystals with it. Try making a borax crystal snowflake ornament during the holiday. You can also try making borax crystal eggs~ see my tutorial on that.
How to Make Borax Crystals:
Powdered Borax– The 20 Mule Team Borax was found in the laundry detergent section
Large Jars or Glasses
Yarn or string
Pencils or craft sticks
The first step to making borax crystals is to make the shapes. We made a variety of shapes. Twist pipe cleaners into different shapes. You can make hearts, snowflakes, stars, or little balls that really hold the crystals together.
Once you have formed your shapes, tie them to a piece of yarn. You will use this to hang them in your jar. Test the length. You do not want the pipe cleaners to touch the sides or the bottom while the crystals are growing in the jar.
Tie the string to the end of your shapes. Tie the other end of the string to a pencil or craft stick. You want the length to be such that the pencil hangs the shape into the middle of jar.
How to Make the Borax Solution:
Fill your jars with several cups of boiling hot water. We just filled our jars mostly of the way fill. Add borax a little at a time to the boiling water, stirring to dissolve after each addition.
You will need 3-4 Tablespoons of borax for every cup of water. I put about 3/4 c. of borax into our jars.
Stir the water and borax solution until you have dissolved the borax. You want a super saturated solution. It is okay if some undissolved borax settles to the bottom of the jar.
If desired, you can add food coloring to the solution if you want even brighter colors. We didn’t add any because the pipe cleaners were colored.
Hang the pipe cleaner snowflake into the jar so that the pencil rests on top of the jar and the pipe cleaner shapes are completely covered with water and hang freely (not touching the bottom of the jar).
Allow the jar to sit in an undisturbed location overnight, or all day if you do it first thing in the morning. As the solution cools, it will form crystals covering the pipe cleaners and even the yarn hanging them. The leftover borax that settles will crystalize at the bottom of the jar, too!
It will take about 12-24 hours, but your pipe cleaners will be covered in beautiful crystals!
When you remove them from the water, they will be wet, so we set them on some paper towels to absorb the extra water as they dry.
You can trim off the strings, or leave them on, It’s up to you.
My kids simply love these pretty crystals! You can hang your borax crystals as a decoration, on a tree, or in a window to catch the sunlight.
Here is a fun old picture from our first time through with the crystal snowflake and oval shaped crystal!
The Science Behind Borax Crystals:
Borax is also known as sodium borate. It is from the mineral Boron.
Crystals are made up of a repeating pattern of connected molecules. They are usually geometric and angular with smooth sides.
Crystals can be formed with a supersaturated liquid. When you dissolve borax into hot water, it can dissolve more than you could dissolve in cold water.
The heat causes the molecules to move away from each other allowing more to dissolve. As the solution cools, the water molecules move closer together allowing the crystals to form. Cool!
Wondering what else to do with your borax after this project? Try making some SLIME with it!