In this amazing growing gummy hearts experiment, your kids will have a blast finding out how big the hearts will grow, how long it will take and if the substance has anything to do with it. This is one experiment your kids will enjoy eating as much as watching. To make it more interesting, use the Scientific Method to help your kids creatively think about what they think will happen and why.
If you enjoy this experiment, you may want to check out our other Valentine’s Day inspired activities! You’ll find an activity for every season.
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What makes the gummy hearts grow?
Because there are two different solutions for this experiment, one being plain water and the other being a salt water mix, there are several scientific factors to consider. If you are using table salt, it is the compound sodium chloride.
If you are using sea salt, then it’s chemical makeup retains more minerals due to coming from evaporated sea water. And there’s also Himalayan salt, which is made up of 98% sodium chloride and the remainder being potassium, magnesium, and calcium.
Of course to see if these individual salts make a difference in the outcome, you’d have to try them all out (which would be another cool experiment)!
With the water-only solution, there are similar factors to include:
- Purified water is water that has been stripped of majority of it’s chemicals and impurities.
- Distilled water is quite like purified water and most of the dissolved substances have been moved by evaporation.
- Spring water is considered the most natural as it uses subterranean water that has risen to the surface.
So, again, in order to see if the kind of water used has an effect in the growing gummy hearts experiment, you’d have to try it with the different types.
Overall, regardless of what kind of salt and water you choose to use, it’s the liquid that will cause the gummy hearts to grow. But how big is the question!
Recommended Science Experiment Books
Love this candy science experiment? Grab one of these science experiment books for even more ideas to help your kids get curious and discover new ideas.
Awesome Science Experiments for Kids: 100+ Fun STEM / STEAM Projects and Why They Work (Awesome STEAM Activities for Kids)The Everything Kids’ Science Experiments Book: Boil Ice, Float Water, Measure Gravity-Challenge the World Around You!Awesome Kitchen Science Experiments for Kids: 50 STEAM Projects You Can Eat! (Awesome STEAM Activities for Kids)Awesome Outdoor Science Experiments for Kids: 50+ STEAM Projects and Why They Work (Awesome STEAM Activities for Kids)Steve Spangler’s Super-Cool Science Experiments for Kids: 50 mind-blowing STEM projects you can do at homeSmithsonian 10-Minute Science Experiments: 50+ quick, easy and awesome projects for kids
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!
The Science Behind the Growing Gummy Hearts Experiment
When the gummies are added to water, the water molecules move into the bear through a process called osmosis. The gelatin ingredient found in the gummies then acts like a sponge and soaks up some of the water. Some may think the water would cause the gummy to dissolve. But it doesn’t.
In the salt water, water moves out of the gelatin because there are more salt molecules in the salt water than there are in the gummy hearts. This may cause the gummy in this solution to shrink – or will it?
There are lots of good hypothetical questions that could be asked beforehand then tested out in this experiment. Be sure to document any questions your kids ask so you can go back and answer them.
For this experiment, you can get all hands on deck. Younger kids can work on their small motor skills by pouring water into a container and stirring salt and water together to create the salt-water solution. For older kids, encourage them to use the Scientific Method and form an educated guess on what they think the end results will be.
Once you have your ingredients together (listed below), make sure you get accurate measurements and have each batch the same weight. If you’d like to get multiple subjects in using this experiment, now is the time for adding in a quick math lesson.
Have your children create a simple graph or chart using the gummy hearts. Create two columns on a piece of paper. In one column your kids can write the number of hearts from one to ten. In the second column they can document the weight of the corresponding number of hearts.
Another math and measurement step in this gummy hearts experiment is weighing them once they have grown. Test your kids addition and subtraction skills by figuring out how much more they weigh since having absorbed some of the water and salt-water solution.
This is something else that can documented on a graph or chart.
- Gummy heart candies
- 1 tablespoon salt
- 2 cups water, divided
- 2 bowls
- In one bowl, add 1 cup water..
- In the other bowl, combine the remaining water with salt, stirring until the salt is dissolved.
- Place two to three gummies in each bowl. Allow to rest for several hours to overnight.
- Observe changes in the gummies.
- If desired, remove the gummies from water and weigh on a kitchen scale.
To create a measurement foundation, keep several gummies out to serve as the control. Then you’ll be able to measure the growth based from the original shape and size.
Ask your kids to describe what they see and what they thought the end result of the growing gummy hearts experiment would be.
I’d like to hear from you! Did you do this experiment? Let me know in the comments below!