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  2. Photochemical smog - Wikipedia

    en.wikipedia.org/wiki/Smog

    The chemical reactions that form smog following a volcanic eruption are different than the reactions that form photochemical smog. The term smog encompasses the effect when a large number of gas-phase molecules and particulate matter are emitted to the atmosphere, creating a visible haze. The event causing a large number of emissions can vary ...

  3. Peroxyacyl nitrates - Wikipedia

    en.wikipedia.org/wiki/Peroxyacyl_nitrates

    In organic chemistry, peroxyacyl nitrates (also known as Acyl peroxy nitrates, APN or PANs) are powerful respiratory and eye irritants present in photochemical smog. They are nitrates produced in the thermal equilibrium between organic peroxy radicals by the gas -phase oxidation of a variety of volatile organic compounds (VOCs), or by aldehydes ...

  4. Peroxyacetyl nitrate - Wikipedia

    en.wikipedia.org/wiki/Peroxyacetyl_nitrate

    It is a secondary pollutant present in photochemical smog. [1] It is thermally unstable and decomposes into peroxyethanoyl radicals and nitrogen dioxide gas. [2] It is a lachrymatory substance, meaning that it irritates the lungs and eyes. [3] Peroxyacetyl nitrate, or PAN, is an oxidant that is more stable than ozone. Hence, it is more capable ...

  5. Air pollution - Wikipedia

    en.wikipedia.org/wiki/Air_pollution

    Photochemical and chemical reactions involving it fuel many of the chemical activities that occur in the atmosphere during the day and night. It is a pollutant and a component of smog that is produced in large quantities as a result of human activities (mostly the combustion of fossil fuels). [85]

  6. Atmospheric chemistry - Wikipedia

    en.wikipedia.org/wiki/Atmospheric_chemistry

    Atmospheric chemistry is a multidisciplinary field with wide-ranging applications that influence environmental policy, human health, technology development, and climate science. Examples of problems addressed in atmospheric chemistry include acid rain, ozone depletion, photochemical smog, greenhouse gasses and global warming. By developing a ...

  7. Ground-level ozone - Wikipedia

    en.wikipedia.org/wiki/Ground-level_ozone

    exert a considerable impact on global warming, because it is a key air pollutant and greenhouse gas, and; impact the production of surface level ozone (contributing again to climate change). As a result, photochemical smog pollution at the earth's surface, as well as stratospheric ozone depletion, have received a lot of attention in recent years.

  8. NOx - Wikipedia

    en.wikipedia.org/wiki/NOx

    The presence of photochemical smog increases during the summer when the incident solar radiation is higher. The emitted hydrocarbons from industrial activities and transportation react with NO x quickly and increase the concentration of ozone and peroxide compounds, especially peroxyacetyl nitrate (PAN).

  9. Atmospheric science - Wikipedia

    en.wikipedia.org/wiki/Atmospheric_science

    The composition of the Earth's atmosphere has been changed by human activity and some of these changes are harmful to human health, crops and ecosystems. Examples of problems which have been addressed by atmospheric chemistry include acid rain, photochemical smog and global warming.