View full lesson: http://ed.ted.com/lessons/why-does-ice-float-in-water-george-zaidan-and-charles-morton

Water is a special substance for several reasons, and you may have noticed an important one right in your cold drink: ice. Solid ice floats in liquid water, which isn't true for most substances. But why? George Zaidan and Charles Morton explain the science behind how how hydrogen bonds keep the ice in your glass (and the polar ice caps) afloat.

Lesson by George Zaidan and Charles Morton, animation by Powerhouse Animation Studios Inc.