Color changing slime takes slime making to the next level. All the fun of playing with slime and then while playing with it the colors change. This easy to make slime that changes colors is not only super fun to play with but also a great way to teach kids about Thermochromism!

Color Changing Slime
We love slime and what makes slime even more fun? Having slime change colors as you play with it of course! This slime that changes colors has all the fun of normal slime but with different temperatures the colors change and it makes this slime even more loved by the kids.
The kids were so excited when I told them we were going to make color changing slime and had a ton of fun playing with it and then seeing what items around the house would make it change colors. They had a blast not only playing with it but seeing what things around the house from the fridge to their hands would make the slime go from one color to the next.
If you are looking for a hands on science experiment to teach the kids about Thermochromism, this color changing slime is perfect. The kids can see how Thermochromism works in action when temperatures are changed.

What is Color Changing Slime?
Color changing slime is a fun homemade slime that when played with and temperatures are changed the colors change. Depending on the Thermochromic Pigment that you use depends on the colors that the slime will change to be.
What is Thermochromism?
Thermochromism is the ability of a substance to change colors depending on the temperature. To make this happen with slime you will use Thermochromic Pigment mixed in with the traditional slime ingredients.

What is Thermochromic Pigment?
Thermochromic Pigment is a pigment that is added to slime to have the color changing process happen. when warmed or cooled will change colors. The basics are that the powder is a temperature sensitive powder that alternates between two colors when warmed and cooled. It is so much fun to use when making slime!
You can use Thermochromic Pigment with any slime you are making including Floam slime, Glow in the Dark slime and glitter glue slime!
What Thermochromic Pigment Should I use?
There is crystal and powder Thermochromic Pigment, I like the powder one for making slime. I like this set of pigments, you can find it on amazon and it comes with 5 different colors. Each pigment color changes to be a different color based on temperature – Orange to Yellow, Dark Green to Lime, Purple to Pink, Cyan to Greenyellow, and Violet to Blue.

The Science behind making slime
While slime is a fun activity to do with the kids it is also a science experiment. It is actually ALL science that makes slime actually work when you are making it.
Slime is the end result when there are the correct ratio of polymers to borate ions. To make slime you need both polymers and ions. Most slime recipes are based on a reaction between the polymers in glue and the borate ions in Borax, saline solution or starch. At times there are additional items added to give different textures to the slime, but the basic chemical reaction to get slime is the same.
How Do you make Color changing slime change colors?
When you change the temperature of the slime the colors will change. You can put the slime in sunlight, rub with your hands, rub with an ice cube, rub your hands with an ice cube and then play with the slime. We also have fun seeing what the color changes are when we put the slime on the side of a cold soda can from the fridge or a warm cup of hot chocolate.

How to Make Slime with Different Colors
If you want to have a slime that changes lots of different colors make a few batches of slime and add a different Thermochromic Pigment to each one and then twist them together. As you play with them you will have multi-colored slime that changes color!
How Do You Play With the Thermochromic Slime?
Color changing slime is played with just like any other slime, but made even more fun because you can put it on other items that are warm and cold to see the changes happen. You can also see the color-changing effects while you are playing with it.

Tips for Making The Best Slime
If you have never made slime with pigment before here are a few tips to make sure you have an easy and fun slime making time.
Add the pigment and mix well, you want to make sure you blend it in and it is a must to do before you add any contact solution.
Slowly add the contact solution into the glue. Adding it in too quickly causes it to get firm. You may not use all of the contact solution or you might need a little bit more contact solution to get the consistency the way you like it.
We like using plastic spoons instead of metal ones when we are making slime. We find that it stirs better with a plastic spoon.
Have special utensils for making slime. We have specific measuring cups, measuring spoons, spoons and bowls that we use to make slime with. Using the ones from your kitchen is not a good idea. You will want to use them to eat and slime is not something you want to be mixing with your food.
Have fun. The most important part of making slime is to have fun. Yes it gets messy, but that is a big part of the fun in making slime.
Is Slime messy?
Now I know the first thing a lot of people ask when they hear about making slime is, Is making slime messy? Well it is but it is a TON of fun too! The next question I get asked is How do you make slime? It is REALLY easy to make slime as long as you follow the directions that we give you.
There are many different ways to make slime and all of them are really fun! Our slime recipes are all no borax slime recipes, because I do not like to use borax around the littlest one so we stick with safe slime ingredients when making our slime.

How to Store Slime
When you are done making your slime, store it in an airtight container. When you go to play with it again you may find a little bit of liquid in the container too. Just mix in the liquid back into the slime with your hands.
How to Make Slime Stretchy again
If you are wanting to make it super stretchy after it has been stored in an airtight container, place it in warm water for 30 seconds to clean it up and get it stretchy again.
Supplies Needed for Color Changing Slime
You will need a spoon and a bowl. I highly recommend having a separate craft bowl and spoon then what you use in your kitchen with food as you are using chemicals and you do not want them to mix with your food.

Color changing slime ingredients
- 5 ounces Clear Glue. We have tried off brand glues and they are not the best for making slime, the only glue we like to use when making slime is Elmers.
- 1 tablespoon Baking Soda.
- 2 teaspoons Saline Solution. The brand of contact solution you use is not important, but you need to make sure that it has boric acid in it.
- 1 teaspoon Thermochromic Pigment.
How to Make Color Changing Slime
In a plastic, or glassbowl (one that you do not use for food) add the glue and the baking soda. Mix the glue and baking soda together until completely combined.

Add the pigment into the glue and baking soda mixture and stir until combined.

Add the saline solution a little at a time and mix together until stiff and slime-like. While you are mixing the saline into the glue it will start to pull from the sides of the bowl forming the slime.
You want to add the saline to the glue slowly otherwise you will have slime that is too hard. If after adding the 2 teaspoons of saline solution the slime is still sticky and not forming, add a TINY amount of saline solution at a time until the slime has formed.
Once the slime has formed, remove it from the bowl and knead it and play with it
Color Changing Slime

Color changing slime takes slime making to the next level. All the fun of playing with slime and then while playing with it the colors change.
Materials
- 5 ounces Clear Glue.
- 1 tablespoon Baking Soda.
- 2 teaspoons Saline Solution.
- 1 teaspoon Thermochromic Pigment.
Instructions
- In a plastic bowl add the glue and the baking soda. Mix the glue and baking soda together until completely combined.
- Add the pigment into the glue and baking soda mixture and stir until combined.
- Add the saline solution a little at a time and mix together until stiff and slime-like. While you are mixing the saline into the glue it will start to pull from the sides of the bowl forming the slime.
- You want to add the saline to the glue slowly otherwise you will have slime that is too hard. If after adding the 2 teaspoons of saline solution the slime is still sticky and not forming, add a TINY amount of saline solution at a time until the slime has formed.
- Once the slime has formed, remove it from the bowl and knead it and play with it