Family mode

Watch this one together

~6 min · materials: optional: clear glass, cooking oil, colored water, corn syrup, and small test objects with adult supervision.

Can stacked liquids catch an object that sinks in water?

Oil in salad dressing separates from the watery ingredients after shaking because oil does not dissolve in water.

Talk about it

  • Use one measuring spoon to compare equal volumes. Why would whole-bottle weight be an unfair test?
  • Pour the liquids slowly in another order. Which bands appear for a while, and which boundary starts to blur?
  • Place a new object's density between two liquids before predicting its trip while the bands remain separate.
Watch it together

no login · nothing saved · pass the phone around

Daytime browsing? Explore every question · Teaching a room? Classroom mode