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How to Do the Dancing Hearts Science Experiment with 2 Ingredients

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Do you love seasonal science experiments? You’ll love this science experiment for kids featuring Valentine science. If you are doing this experiment at home, focus on the science of chemical reactions when doing the dancing hearts science experiment.

If you are doing this STEM activity in the classroom, this experiment is fifth grade NGSS aligned and fits into the chemical reaction theme. If you are learning about chemical reactions and properties of matter in February, this is the perfect Valentine science experiment!

Add the dancing candy heart experiment to your Valentine candy science experiments!

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Fun Dancing Hearts Science Experiment for Valentine’s Day!

If your kids aren’t in fifth grade, they can still do this experiment. Even preschoolers will love completing the dancing conversation hearts science experiment.

NGSS Chemistry Alignment for this Science Demonstration

  • 5-PS1-1. Develop a model to describe that matter is made of particles too small to be seen.
  • 5-PS1-3. Make observations and measurements to identify materials based on their properties.
  • 5-PS1-4. Conduct an investigation to determine whether the mixing of two or more substances results in new substances.
Love Valentine’s Day? Love science? You’ll have a blast with this dancing conversation heart Valentine science project! #valentinesday #scienceforkids #science #scienceexperiments #stemed #stem #handsonlearning

How Does the Science Experiment with Conversation Hearts Work?

Unsweetened soda contains water and carbon dioxide gas to make the soda bubbly. When the bottle is sealed, you can’t see these gas bubbles. Why not? Soda is pressurized during manufacturing which prevents the gas from escaping the liquid.

But when the soda is exposed to air, the CO2 gas tries to escape because CO2 is lighter than water and air.

Even though conversation hearts are denser than the water and gas in the soda, they still contain a lot of air.

When the carbon dioxide bubbles get stuck on the edges of the candy, eventually, the gas builds up so that the candy is brought to the surface of the jar along with the CO2 gas.

When the gas releases, the candy falls back to the bottom of the jar and the process is repeated.

The dancing candy hearts stop once the CO2 has escaped from the soda.

Don’t forget to check out all of our Valentine STEM activities!

How to Do the Dancing Hearts Science Experiment

This Valentine science activity is the perfect way to use up conversation hearts! Any brand of conversation hearts or candy hearts will work!

What You Need to Do the Conversation Hearts Science Experiment

You will need the following supplies when doing the dancing hearts science experiment.

valentine stem challenges

Science Questions for the Dancing Conversation Hearts Experiment

Love Valentine’s Day? Love science? You’ll have a blast with this dancing conversation heart Valentine science project! #valentinesday #scienceforkids #science #scienceexperiments #stemed #stem #handsonlearning

What other materials create CO2 when mixed?

Does altering the amount of soda or candy change what happens?

How long does it take before the converstaion hearts start dancing?

Does the reaction change if the soda is heated or cooled to nearly freezing temperatures?

Step-by-Step Directions for the Dancing Hearts Science Experiment

dancing candy hearts science experiment

Fill a jar about 3/4 of the way full with sparkling soda.

Drop in a few conversation hearts.

dancing candy hearts science experiment

Start the timer.

Watch as the candy hearts start to rise to the top of the jar, then fall back to the bottom of the jar.

dancing candy hearts science experiment

Calculate how long it takes each conversation heart to rise and fall in the jar, and how long it takes before the CO2 gas escapes and can no longer lift the candies to the top of the jar.

valentine stem challenges

More Valentine Activities to Try

Valentine’s Day Lava Lamp Science Experiment

Magic Erupting Color Reveal Science Valentines for Kids

How to Make Glitter Slime That Sparkles and Shines

Squishy Valentines for Kids

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