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A photon hits an oxygen molecule. The energy from the photon breaks the molecule apart. The molecule becomes two separate oxygen atoms. This is an example of photodissociation.
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Photodissociation

Photons are little bits of light. Photons carry energy.

When a photon hits a molecule, it adds energy to the molecule. The molecule has chemical bonds (they work a bit like stretchy rubber bands!) holding its atoms together. Sometimes the energy from the photon breaks the bond between some of the atoms in a molecule. The atoms fly apart! This is called photodissociation.

Photons of ultraviolet (UV) "light" carry more energy than photons of visible light carry. Sometimes it takes high-energy UV photons to break a molecule apart!

Last modified February 8, 2006 by Randy Russell.

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