When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Ozone - Wikipedia

    en.wikipedia.org/wiki/Ozone

    Ozone generators sold as air cleaners intentionally produce the gas ozone. [43] These are often marketed to control indoor air pollution, and use misleading terms to describe ozone. Some examples are describing it as "energized oxygen" or "pure air", suggesting that ozone is a healthy or "better" kind of oxygen. [43]

  3. Ground-level ozone - Wikipedia

    en.wikipedia.org/wiki/Ground-level_ozone

    Ground-level ozone (O 3), also known as surface-level ozone and tropospheric ozone, is a trace gas in the troposphere (the lowest level of the Earth's atmosphere), with an average concentration of 20–30 parts per billion by volume (ppbv), with close to 100 ppbv in polluted areas.

  4. Ozone–oxygen cycle - Wikipedia

    en.wikipedia.org/wiki/Ozone–oxygen_cycle

    If an oxygen atom and an ozone molecule meet, they recombine to form two oxygen molecules: 4. ozone conversion: O 3 + O → 2 O 2. Two oxygen atoms may react to form one oxygen molecule: 5. oxygen recombination: 2O + A → O 2 + A as in reaction 2 (above), A denotes another molecule or atom, like N 2 or O 2 required for the conservation of ...

  5. Allotropes of oxygen - Wikipedia

    en.wikipedia.org/wiki/Allotropes_of_oxygen

    Triatomic oxygen (ozone, O 3) is a very reactive allotrope of oxygen that is a pale blue gas at standard temperature and pressure. Liquid and solid O 3 have a deeper blue color than ordinary O 2, and they are unstable and explosive. [5] [6] In its gas phase, ozone is destructive to materials like rubber and fabric and is damaging to lung tissue ...

  6. Ozone layer - Wikipedia

    en.wikipedia.org/wiki/Ozone_layer

    When ozone is produced by solar UV radiation in the tropics, it is done so by circulation lifting ozone-poor air out of the troposphere and into the stratosphere where the sun photolyzes oxygen molecules and turns them into ozone. Then, the ozone-rich air is carried to higher latitudes and drops into lower layers of the atmosphere. [11]

  7. Ozone depletion - Wikipedia

    en.wikipedia.org/wiki/Ozone_depletion

    Three forms (or allotropes) of oxygen are involved in the ozone-oxygen cycle: oxygen atoms (O or atomic oxygen), oxygen gas (O 2 or diatomic oxygen), and ozone gas (O 3 or triatomic oxygen). [15] Ozone is formed in the stratosphere when oxygen gas molecules photodissociate after absorbing UVC photons. This converts a single O 2 into two atomic ...

  8. Geological history of oxygen - Wikipedia

    en.wikipedia.org/wiki/Geological_history_of_oxygen

    Oxygen began building up in the prebiotic atmosphere at approximately 1.85 Ga during the Neoarchean-Paleoproterozoic boundary, a paleogeological event known as the Great Oxygenation Event (GOE). At current rates of primary production, today's concentration of oxygen could be produced by photosynthetic organisms in 2,000 years. [4]

  9. Oxygen - Wikipedia

    en.wikipedia.org/wiki/Oxygen

    Oxygen gas is the second most common component of the Earth's atmosphere, taking up 20.8% of its volume and 23.1% of its mass (some 10 15 tonnes). [19] [70] [d] Earth is unusual among the planets of the Solar System in having such a high concentration of oxygen gas in its atmosphere: Mars (with 0.1% O 2 by volume) and Venus have much less. The O