Density refers to the amount of stuff there is in a given space. Different things have different densities. For example, a cup of water has more stuff in it than a cup of oil. The water is denser. A marble and a ball of the exact same size are made of different amounts of stuff – they have different densities. Do you think the less dense oil will sink in or float on the denser water? Which is denser, the marble or the ball? How can you tell?
How do liquids of various densities interact with each other?
- Measuring cup
- Clear glass jar (labels removed)
- ½ cup water
- Food coloring
- ½ cup corn syrup
- ½ cup vegetable oil
- Small rubber ball of approximately the same size as marble
- Circle of carrot, mini marshmallow, other small objects
- Pour the water into the jar.
- Color it with food coloring.
- Pour the corn syrup into the jar. What happens?
- Carefully pour the oil into the jar. What happens?
- Drop the marble into the jar. Does it float? Sink?
- Drop the ball into the jar. Does it float? Sink?
- Continue dropping objects into the jar and observing what happens.
- What can you tell about the densities of the liquids and the objects?
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