It is an unstable molecule that readily combines with other atoms. Ozone has the same chemical structure whether it is found in the stratosphere or the troposphere . Where we find ozone in the atmosphere determines whether we consider it to be Dr. Jekyll or Mr. Hyde. It is a key ingredient of urban smog. Electromagnetic energy is sometimes described as traveling in waves and sometimes as traveling in packets of energy referred to as photons.
Short wavelengths have more energy per photon than long wavelengths.
Ozone is constantly being formed in the earth's atmosphere by the action of the sun's ultraviolet radiation on oxygen molecules. Ultraviolet light splits the molecules apart by breaking the bonds between the atoms. A highly reactive free oxygen atom then collides with another oxygen molecule to form an ozone molecule. Because ozone is unstable, ultraviolet light quickly breaks it up, and the process begins again. Ozone in the Stratosphere Ozone and oxygen molecules in the stratosphere absorb ultraviolet light from the sun, providing a shield that prevents this radiation from passing to the earth's surface.