Classroom mode

Run it in class

Why do oil and water return to separate layers after shaking?

Show of hands — before you project anything

Why does dividing the same oil into more droplets increase the total boundary?

  • A Way more than you'd guess
  • B About what you'd guess
  • C Way less than you'd guess

Count the votes out loud. Hold them to it — then watch.

Project it (fullscreen)

Discussion prompts

  • Why does dividing the same oil into more droplets increase the total boundary?
  • How is a cloudy droplet dispersion different from a dissolved solution?
  • Which part of the story is about molecular preference, and which part is about gravity and density?

Where it shows up in real life

  • Oil-and-vinegar dressing that becomes cloudy when shaken and later returns to two regions
  • A rainbow oil sheen that gathers into patches on a puddle
  • Tiny oil droplets briefly spread through dishwater after a greasy pan is swirled

A prediction-first worksheet — no answer key.

zero prep · no login · any projector

Winding down at home? Family mode · Explore every question