Surface tension | Middle school chemistry | Khan Academy

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Cohesion causes water particles to attract and hold together, leading to fascinating effects like surface tension. At the surface, water molecules pull inward, creating a "skin" that's stronger than the liquid below. This tension allows water striders to walk on water and paperclips to float, highlighting the unique behavior of water’s cohesive forces.

00:00 Intro
00:21 What is surface tension?
02:49 How do water striders walk on water?
04:06 Why water forms droplets
04:41 Summary

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