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The chemistry of cold packs - John Pollard

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If you stick water in the freezer, it will take a few hours to freeze into ice. How is it, then, that cold packs go from room temperature to near freezing in mere seconds? John Pollard details the chemistry of the cold pack, shedding light on the concepts of energetics and entropy along the way.

The breaking of bonds on the molecular level always requires an input of energy. Therefore forming bonds always releases energy. Based on this, build an explanation for why a reaction would release heat (exothermic) and why a reaction would consume heat (endothermic).

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Meet The Creators

  • Educator John Pollard
  • Animator Henry Chung, Mark Storer, Noel Wong, Michael Field
  • Compositor Ricky Earl
  • Artist Ieuan Protheroe
  • Script Editor Alex Gendler
  • Narrator Addison Anderson

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