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With Explore the Planets, investigate the planets, their moons, and understand the processes that shape them. By G. Jeffrey Taylor, Ph.D. See our DVD collection.

Photodissociation of Water (H2O)

Photodissociation of water.
Animation courtesy COMET.

This movie shows how an ultraviolet (UV) photon can break apart a water molecule. When the photon hits the water molecule (H2O), it adds energy to the molecule. The extra energy breaks one of the bonds between the oxygen atom and a hydrogen atom. The hydrogen atom (H) flies away from the piece that's left, which is called a hydroxyl radical (OH).

This is called photodissociation.

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Photodissociation of Molecular Nitrogen

Photodissociation of Molecular Oxygen

Photodissociation of the Hydroxyl Radical

Last modified February 17, 2006 by Randy Russell.

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