When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. 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 ...

  3. Ozone - Wikipedia

    en.wikipedia.org/wiki/Ozone

    It is often used in conjunction with oxygen and hydrogen peroxide to eliminate the need for chlorine-containing compounds in the manufacture of high-quality, white paper. [156] Ozone can be used to detoxify cyanide wastes (for example from gold and silver mining) by oxidizing cyanide to cyanate and eventually to carbon dioxide. [157]

  4. Ground-level ozone - Wikipedia

    en.wikipedia.org/wiki/Ground-level_ozone

    The IPCC believes that "measured stratospheric O3 losses over the past two decades have generated a negative forcing of the surface-troposphere system" of around 0.15 0.10 watts per square metre (W/m 2). [39] Furthermore, rising air temperatures often improve ozone-forming processes, which has a repercussion on climate, as well.

  5. Ozone layer - Wikipedia

    en.wikipedia.org/wiki/Ozone_layer

    Ozone-oxygen cycle in the ozone layer. The Earth's ozone layer formed about 500 million years ago, when the neoproterozoic oxygenation event brought the fraction of oxygen in the atmosphere to about 20%. [7] The photochemical mechanisms that give rise to the ozone layer were discovered by the British physicist Sydney Chapman in 1930.

  6. 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]

  7. Oxygen cycle - Wikipedia

    en.wikipedia.org/wiki/Oxygen_cycle

    The word oxygen in the literature typically refers to the most common oxygen allotrope, elemental/diatomic oxygen (O 2), as it is a common product or reactant of many biogeochemical redox reactions within the cycle. [2] Processes within the oxygen cycle are considered to be biological or geological and are evaluated as either a source (O 2 ...

  8. Chemical cycling - Wikipedia

    en.wikipedia.org/wiki/Chemical_cycling

    The majority of known chemical cycles on Venus involve its dense atmosphere and compounds of carbon and sulphur, the most significant being a strong carbon dioxide cycle. [3] The lack of a complete carbon cycle including a geochemical carbon cycle, for example, is thought to be a cause of its runaway greenhouse effect , due to the lack of a ...

  9. Allotropes of oxygen - Wikipedia

    en.wikipedia.org/wiki/Allotropes_of_oxygen

    There are several known allotropes of oxygen. The most familiar is molecular oxygen (O 2), present at significant levels in Earth's atmosphere and also known as dioxygen or triplet oxygen. Another is the highly reactive ozone (O 3). Others are: Atomic oxygen (O 1), a free radical. Singlet oxygen (O * 2), one of two metastable states of ...