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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Related links:

Photodissociation of Molecular Nitrogen (movie)

Photodissociation of Molecular Oxygen (movie)

Photodissociation of Water (movie)

Photodissociation of the Hydroxyl Radical (movie)

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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