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Why does ice float in water? - George Zaidan and Charles Morton

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Exploring our Oceans

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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.

In our two-dimensional molecular picture of ice (at 2:30), how many hydrogen atoms surround every oxygen atom? How many oxygen atoms surround every hydrogen atom? But remember that real life is three-dimensional. Do some research and find the most molecular common structure of ice. Study it closely and figure out how many hydrogens surround each oxygen and how many oxygens surround each hydrogen. Is our 2D model a good approximation for the 3D reality? Why or why not?

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Watch the video and finish the Think section to complete the lesson.

About Exploring our Oceans

Exploring our Oceans offers insight into the scientific marvels of the marine world, and the part you can play in uncovering the ocean's mysteries and safeguarding its future. From biology to physics to engineering, understanding our oceans involves a multitude of scientific approaches. Dive into our curated videos and supporting lesson materials, and find out how you can be a part of it all.

Meet The Creators

  • Video created by TED-Ed
  • Lesson Plan created by Luka Seamus Wright

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