With the rainbow density jar, learn about the density of various liquids in a fun, colorful way! Science experiments for kids have never been so happy! Kids will love mixing the colors, adding layers to their density jar, and watching to see which layers fall to the bottom, and which rise to the top. Drop in coins and other objects of varying weights and see where they stick among the layers to make this a STEM activity. It’s the perfect activity to try as part of St. Patrick’s Day STEM activities!
This fun rainbow density jar is a quick way to explain the concept of density to kids. Kids will love making and observing the liquids in the rainbow density jar.
Rainbow Density Jar Science Experiment
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What you’ll need for the rainbow density jar:
- Shaving cream
- Clear hand soap
- Maple syrup
- Corn syrup
- Food coloring (red, orange, yellow, green, blue, purple)
- 7 small containers
- 1 large mason jar
- Measuring cup (we like stainless steel cups)
Pour about 1/3 of a cup of each liquid into six small bowls.
Add color to each of your materials. Make the shaving cream red, the water orange, the soap yellow, the maple syrup green, the corn syrup blue, and the honey purple.
Add the liquids to the jar in reverse order (purple, blue, green, yellow, orange, red).
Wait about an hour to allow the colors to settle.
Place your jar in a sunny location to see all the layers.
Let your kids observe what happened to the liquids. Why are they not mixing with one another? Honey is the densest liquid, while shaving cream is the least dense. Let the kids try to figure out why the shaving cream is so much less dense than the honey.
The Science Behind the Rainbow Density Jar
This science experiment is a quick and easy demonstration of density. Density is how much mass is contained in a volume of measurement (D=M/V). Density is the measurement of how closely molecules are packed together in a given material (in this case, liquids). If the mass of a liquid increases but the volume is the same (as is the case with this experiment), the density increases. Honey has molecules that are the closest together, while shaving cream is the least dense material.
Try adding various objects from around the house to see which are more or less dense than the liquids in your jar.
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