Ozone is a highly reactive form of oxygen.
As chemicals go, ozone is chemically unstable, and when left to its own devices, it doesn't linger long. It is also extremely reactive with other compounds. This can be good or bad, depending on where the ozone molecules happen to be. Ozone When ozone occurs in the upper atmosphere, it filters out harmful ultraviolet rays from the sun. Unfortunately, because ozone is so highly reactive, other chemicals can easily bond with the ozone molecules, depleting the protective ozone layer.