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  2. Ozone - Wikipedia

    en.wikipedia.org/wiki/Ozone

    According to the American Lung Association, the Denver–Aurora area is the 14th most ozone-polluted area in the U.S. [65] The problem of high ozone levels is not new to this area. In 2004, the EPA allotted the Denver Metro /North Front Range [ b ] as non-attainment areas per 1997's 8-hour ozone standard, [ 66 ] but later deferred this status ...

  3. Ozone and biology - Wikipedia

    en.wikipedia.org/wiki/Ozone_and_biology

    Ozone cycle illustrated over image by NASA astronaut Scott Kelly. Ozone is a ubiquitous yet highly reactive molecule in the atmosphere. Such a highly reactive oxidizer would normally be dangerous to life but ozone's concentration at sea level is usually not high enough to be toxic.

  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. Composition of the human body - Wikipedia

    en.wikipedia.org/wiki/Composition_of_the_human_body

    Water is ~11% hydrogen by mass but ~67% hydrogen by atomic percent, and these numbers along with the complementary % numbers for oxygen in water, are the largest contributors to overall mass and atomic composition figures. Because of water content, the human body contains more oxygen by mass than any other element, but more hydrogen by atom ...

  6. Ozone layer - Wikipedia

    en.wikipedia.org/wiki/Ozone_layer

    UV-A does not primarily cause skin reddening, but there is evidence that it causes long-term skin damage. Although the concentration of the ozone in the ozone layer is very small, it is vitally important to life because it absorbs biologically harmful ultraviolet (UV) radiation coming from the Sun. Extremely short or vacuum UV (10–100 nm) is ...

  7. Oxygen compounds - Wikipedia

    en.wikipedia.org/wiki/Oxygen_compounds

    Its bulk properties partly result from the interaction of its component atoms, oxygen and hydrogen, with atoms of nearby water molecules. Hydrogen atoms are covalently bonded to oxygen in a water molecule but also have an additional attraction (about 23.3 kJ·mol −1 per hydrogen atom) to an adjacent oxygen atom in a separate molecule. [2]

  8. Properties of water - Wikipedia

    en.wikipedia.org/wiki/Properties_of_water

    Water molecules stay close to each other , due to the collective action of hydrogen bonds between water molecules. These hydrogen bonds are constantly breaking, with new bonds being formed with different water molecules; but at any given time in a sample of liquid water, a large portion of the molecules are held together by such bonds. [61]

  9. Allotropes of oxygen - Wikipedia

    en.wikipedia.org/wiki/Allotropes_of_oxygen

    Tetraoxygen had been suspected to exist since the early 1900s, when it was known as oxozone. It was identified in 2001 by a team led by Fulvio Cacace at the University of Rome. [ 13 ] The molecule O 4 was thought to be in one of the phases of solid oxygen later identified as O 8 .