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K-5Walking Water Rainbow
Watch water climb out of one cup and walk itself into the next, building a rainbow out of nothing but paper towels!
Video coming soon!
This experiment hasn't been filmed yet — check back after the next SASSY Science classroom visit.
What you need
- 6 clear cups
- Paper towels
- Water
- Red, yellow, and blue food coloring
Why it works
Paper towels are made of tiny fibers with even tinier gaps between them. Water molecules stick to those fibers and to each other, so the water climbs up the towel and 'walks' across into the empty cup — that's called capillary action. Watching the colors mix along the way also shows how primary colors combine to make new ones.
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