ozone

(noun)

A triatomic molecule, consisting of three oxygen atoms. It is an allotrope of oxygen that is much less stable than the diatomic allotrope (O2), breaking down with a half life of about half an hour in the lower atmosphere, to normal dioxygen. Ozone is formed from dioxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere. In total, ozone makes up only 0.6 parts per million of the atmosphere.

Related Terms

Examples of ozone in the following topics:

  • Elements of Life

    • The Oparin-Haldane hypothesis suggests that the atmosphere of the early Earth may have been chemically reducing in nature, composed primarily of: methane (CH4), ammonia (NH3), water (H2O), hydrogen sulfide (H2S), carbon dioxide (CO2) or carbon monoxide (CO), with phosphate (PO43-), molecular oxygen (O2) and ozone (O3) either rare or absent.

  • Cholera

    • Antibacterial treatment of general sewage by chlorine, ozone, ultraviolet light or other effective treatment before it enters the waterways or underground water supplies helps prevent undiagnosed patients from inadvertently spreading the disease.
    • All water used for drinking, washing, or cooking should be sterilized by either boiling, chlorination, ozone water treatment, ultraviolet light sterilization (e.g. by solar water disinfection), or antimicrobial filtration in any area where cholera may be present.

  • Electron Donors and Acceptors in Anaerobic Respiration

    • Complete denitrification is an environmentally significant process because some intermediates of denitrification (nitric oxide and nitrous oxide) are important greenhouse gases that react with sunlight and ozone to produce nitric acid, a component of acid rain.

  • Microbes and the Origin of Life on Earth

    • The atmosphere lacked oxygen, and an ozone layer did not yet protect Earth from harmful radiation.

  • Nitrate Reduction and Denitrification

    • Complete denitrification is an environmentally significant process because some intermediates of denitrification (nitric oxide and nitrous oxide) are significant greenhouse gases that react with sunlight and ozone to produce nitric acid, a component of acid rain.