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Christmas is coming and we are busy creating lots of new Christmas-themed learning ideas over here. I want to share our latest Christmas science experiment with you. Have you ever grown a crystal tree before? If not, it’s worth trying!
I have purchased these “magic crystal trees” in little kits before in the past, but this time we learned how to make it all on our own. It’s quite easy to make!
This science project use strong chemicals, so you definitely need an adult present. You’ll not want to let kids touch the chemicals as you mix and prepare. Kids can help with all of the other steps, though.
How to Grow a Crystal Christmas Tree
- Cardboard- we used the back piece of some old notebooks.
- Laundry Bluing– a solution used in laundry to make whites look brighter, can be found in laundry sections of the grocery store.
- Table Salt
- Small Dishes– we used plastic petri dishes
- Food Coloring (optional, but more fun!)
Start by making the cardboard trees. Draw the tree shape on your piece of cardboard. Cut three trees that are the same size and shape out of a thin cardboard.
(We also made a snowman, but the tree worked better due to the many points allowing spaces for the crystals for form.)
It will need to have a large base that will stand up flat in your dish.
Cut slits in the tree pieces. Two of them need slits from the top of the tree going down and the third one from the bottom to the top. Cut them really skinny and halfway through the shape. The ones with the slits on top, need to be folded to a 90 degree angle.
Fit the three pieces together by cutting the two with the slit on top back to back and sliding the one with the slit on the bottom over the top. Place them in your dishes.
Next we colored the edges of the trees. You could do this with marker, or paint, or food coloring. My kids painted on food coloring so it would be really concentrated.
How To Make the Crystal Tree Solution
To make the solution for this Christmas science experiment, mix together the following:
2 Tbsp of Salt
2 Tbsp warm water
2 Tbsp of Bluing
1 Tbsp ammonia
Several drops of food coloring.
Mix it all together until the salt is fully dissolved.
Next, pour the “magic” solution over your tree. Let it sit untouched over night to grow the crystals.
We checked on it after a few hours and already saw some salt crystal growth. Pretty cool, isn’t it?!
The next day the crystals were fully formed. They are beautiful, right? What we love about them is that they are soft and fluffy to the touch. They fall off when you touch them, so these are not sturdy crystals that last.
What’s the Science Behind the Crystal Tree Science Experiment?
The liquid in the solution soaks up into the cardboard. This is called capillary action, the same as a tree soaking up water through its roots. Ammonia speeds up the evaporation process. When the liquid is evaporated, it leaves behind the salt and bluing.
Bluing is a colloid, which means it merges with another substance but never fully mixes and does not settle. Water mixes well with other substances because it has a lot of room between the molecules. This allows the bluing to merge easily with it, as well as the salt. When the salt and bluing are left behind after the liquid evaporates, it forms the crystals.