Arrange the following sequential events in the formation of photochemical smog and secondary atmospheric oxidants, starting from initial vehicular emission to final toxic compound synthesis.
- 1Internal combustion engines discharge primary pollutants, predominantly nitric oxide () and unburnt volatile organic compounds (VOCs), into the lower atmosphere.
- 2Emitted nitric oxide () undergoes oxidation by ambient atmospheric oxygen to form toxic, brownish nitrogen dioxide () gas.
- 3Solar ultraviolet (UV) radiation cleaves nitrogen dioxide () through photolysis, yielding nitric oxide () and highly reactive atomic oxygen ().
- 4Free atomic oxygen () binds rapidly with atmospheric molecular oxygen () to synthesize ground-level ozone (), which subsequently reacts with VOCs to produce peroxyacetyl nitrate (PAN).
Cevap
The correct chronological sequence of photochemical smog formation begins with the release of primary emissions (nitric oxide and volatile organic compounds), followed by the atmospheric oxidation of nitric oxide to nitrogen dioxide. Next, solar ultraviolet radiation photolyzes nitrogen dioxide into reactive atomic oxygen, which finally combines with molecular oxygen to produce ground-level ozone and peroxyacetyl nitrate.
The correct sequence accurately reflects the tropospheric chemical reactions driven by solar radiation: combustion releases primary pollutants ( and VOCs), ambient oxygen oxidizes into , solar UV radiation splits into and atomic oxygen (), and free atomic oxygen recombines with molecular oxygen () to form ground-level ozone () and peroxyacetyl nitrate (PAN).
Adım Adım Çözüm
Anahtar Kavram
Photochemical Smog Reaction Mechanism
Tahmini Süre:2m 0s