Photodissociation of Water
The hydroxyl radical (OH) is essentially a piece of a molecule, made up of one oxygen atom and one hydrogen atom. It is highly reactive. It is often produced when a water molecule loses a hydrogen atom. This animation illustrates the process of photodissociation of the hydroxyl radical. When an extreme ultraviolet (EUV) photon strikes the hydroxyl radical (OH) , it photodissociates the radical into two separate parts - a hydrogen atom (H) and an oxygen atom (O). The energy from the photon breaks the chemical bond that holds the atoms together. You will need to have the latest version of the Flash player to see this animation. |
Photodissociation of Molecular Oxygen
Photodissociation of Molecular Nitrogen
The hydroxyl radical (OH) is sort of a piece of a molecule. It is made up of one oxygen atom and one hydrogen atom. One way to make OH is to knock a hydrogen atom off of a water molecule (H2O). This movie shows how an ultraviolet (UV) photon can break apart the hydroxyl radical. When the photon hits the radical, it adds energy to the radical. The extra energy breaks the bond between the oxygen atom and hydrogen atom. The two atoms fly apart! This is called photodissociation. You need the latest version of the Flash player to see this movie. |
The hydroxyl radical (OH) is sort of a piece of a molecule. It has one oxygen atom and one hydrogen atom. One way to make OH is to knock a hydrogen atom off of a water molecule (H2O). This movie shows how ultraviolet "light" can break apart the hydroxyl radical. You need the latest version of the Flash player to see this movie. Photons are little bits of light. Photons carry energy. When a photon hits the hydroxyl radical, it adds energy to the radical. The radical 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 the oxygen atom and the hydrogen atom. The atoms fly apart! When a photon knocks molecules (or the hydroxyl radical) apart, it is called photodissociation. Photons of ultraviolet (UV) light carry more energy than photons of visible light carry. It takes high-energy UV photons to break the hydroxyl radical apart! |
Page created February 17, 2006 by Randy Russell.
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