We’ve found quite a few ways to enjoy slime in our home, so adding this red heart slime recipe to the mix has been a great bonus. Not to mention, it’s the perfect experiment and activity to do for Valentine’s Day.
Keep reading to learn the science behind the slime and just how easy it is to make!
>> See more Valentine’s Day Activities for Kids
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The Science Behind Red Heart Slime
If you think your kids are doing just “another activity,” think again! Making red heart slime is actually science and chemistry. It also works those fine motor skills, critical thinking, and listening skills.
While making it, your kids will have the opportunity to learn about the things they’ll see happening right before their eyes. Seeing the ingredient laid out separately, they (and you) may wonder how they come together to make the red heart slime. Here’s how!
>> See more easy slime recipes
In order to make slime, you’ll need the right kind of ingredients. For starters, you need glue. But not just any kind. Washable school glue, like Elmer’s (classic glitter for this recipe), works the best. Then, you need some slime activators.
These will typically come from the boron family: saline solution, borax powder, or liquid starch. For the red heart slime recipe we will use baking soda and contact lens solution.
When these ingredients come together, they go through a process known as cross-linking. This is a fancy term used in chemistry and biology to explain what happens when one polymer chain (very large molecule) is bonded with another.
Want a fun ready to go Valentine’s kit that will delight your kids? Grab one of these craft or play dough kits from Etsy. They’re super adorable and a great way for new play ideas at home!
Recommended Science Experiment Books
Love making slime? Try these other recipes or have even more fun with new science experiments that you can explore with household items.
Ultimate Slime Extreme Edition: 100 New Recipes and Projects for Oddly Satisfying, Borax-Free Slime — DIY Cloud Slime, Kawaii Slime, Hybrid Slimes, and More!The Slime BookAwesome Science Experiments for Kids: 100+ Fun STEM / STEAM Projects and Why They Work (Awesome STEAM Activities for Kids)The Kitchen Pantry Scientist Chemistry for Kids: Science Experiments and Activities Inspired by Awesome Chemists, Past and Present; Includes 25 … the World (The Kitchen Pantry Scientist, 1)Kitchen Science Lab for Kids: 52 Family Friendly Experiments from Around the House (Lab for Kids (4))The 101 Coolest Simple Science Experiments: Awesome Things To Do With Your Parents, Babysitters and Other Adults
Chemistry in the Red Heart Slime
Once the cross-linking of the ingredients – Elmer’s glitter glue, baking soda, and contact lens solution – have been complete, they begin to change in terms of their atomic and molecular makeup and create a new substance – slime!
The neatest part about creating slime is it becomes a substance known as a non-Newtonian fluid. This means it is neither a solid nor a liquid. When you pick up it, it may feel solid, but will quickly begin to ooze like a liquid!
Slime will also take the shape of the container it is in. And although it doesn’t have a shape of its own, it can still be bounced like a ball due to its elasticity. The chemical bonding of slime will allow you to pull slowly and it stay together.
However, if you pull it quickly, it will break. This happens because you are breaking it’s chemical bond before it can stay together (like when pulling it slowly).
Why Red Slime is Stretchy
Speaking of stretching and pulling slime, your kids may wonder how this is possible. Thanks to the polymers I mentioned earlier, the glue is able to keep its flowing texture but without the drying out or overly sticky feel that you’d normally get with glue.
Looking more closely at how polymers work in the red heart slime, the glue is made up of long chains of polyvinyl acetate molecules. These molecules then bond with the slime activators (baking soda and contact lens solution) and grow through a change of position.
The chemical reaction between the glue and borate ions creates the slime.
Pretty cool, huh?
How to Make Red Heart Slime
First, you’ll want to gather all the supplies listed below. In addition to the main three ingredients use to make the red heart slime, you’ll need a few mixing supplies. Don’t forget we’re making it Valentine’s Day related, so grab some heart gems, beads, and whatever else you want to add.
Also, this recipe is something the entire family can enjoy making together. Get all hands on deck and have a slimey good time! make sure younger kids are supervised at all times as some of the ingredients should not be consumed.
- 1 6oz. Bottle of Red Elmer’s Glitter Glue
- ½ Tbsp. Baking Soda
- 1 ¼ tbsp contact lens solution
- Mixing bowl
- Measuring spoons
- Plastic mat
- Heart gems
Follow these easy 7 steps and your kids will have their red heart slime:
- Pour all of the glue into a mixing bowl.
- Add the baking soda. Stir well until combined.
- Add the contact solution.
- Stir until slime forms.
- Knead the slime with your hands until you get the desired consistency.
- Place the dough on a plastic play mat.
- Add the heart gems and beads.
Side note: If you would like to create slime without using an activator from the borax family, you certainly can! Just know the texture of your slime will be different than the kind made with ingredients listed above. Click here for more information and recipes for borax-free slime.
And there you have it – red heart slime! Did you make this recipe? Let me know in the comments below!