Reactions of Methane and Organic Free Radicals

Hydrocarbons react with oxygen and radicals, producing free radicals and ozone, which are key components in smog formation.

Peroxyacyl nitrates form when acyl peroxy radicals react with nitrate radicals, typically involving aldehydes as intermediates.

Nitrate radicals participate in reactions that regenerate NO2, contributing to the photochemical reactions that lead to ozone formation and smog.

<p>Aldehydes undergo primary photochemical reactions, producing radicals and contributing to the formation of ozone and other secondary pollutants.</p> Signup and view all the answers

<p>Alkenes undergo addition reactions with radicals and ozone, leading to the production of products like aldehydes and organic peroxyl radicals.</p> Signup and view all the answers

<p>Free radicals, such as hydroxyl radicals, interact with other species to create more radicals, maintaining the chain of reactions essential for smog formation.</p> Signup and view all the answers

<p>Hydroxyl radicals are key species in sustaining reactions that lead to the formation of ozone and other smog constituents by reacting with hydrocarbons and other precursors.</p> Signup and view all the answers

<p>Photochemical reactions involving NO2 produce oxygen atoms and contribute to the formation of ozone, leading to poor air quality and increased smog levels.</p> Signup and view all the answers

<p>Ozone (O3)</p> Signup and view all the answers

<p>Terpenes such as isoprene are high contributors to reactive atmospheric hydrocarbons, leading to increased formation of secondary pollutants like ozone.</p> Signup and view all the answers

<p>Photochemical oxidation</p> Signup and view all the answers

<p>Nitrate radicals react with hydrocarbons to form isoprene nitrates, enhancing the production of secondary pollutants.</p> Signup and view all the answers

<p>Carbonyls and organic solids</p> Signup and view all the answers

<p>Hydrocarbon and NO pollution, intense sunlight, and stagnant air.</p> Signup and view all the answers

<p>Maintaining a stoichiometric air/fuel ratio minimizes emissions of hydrocarbons (HC) and reduces nitrogen oxides (NO).</p> Signup and view all the answers

<p>Temperature inversions trap pollutants near the ground, exacerbating the effects of photochemical smog.</p> Signup and view all the answers

<p>Catalytic converters oxidize hydrocarbons and carbon monoxide to reduce NO emissions.</p> Signup and view all the answers

<p>Isoprene and other reactive terpenes.</p> Signup and view all the answers

<p>Hydrocarbons act as precursors, reacting with hydroxyl radicals to form oxidized products such as ROO and HOO, thereby propagating chain reactions that contribute to smog.</p> Signup and view all the answers

<p>Peroxyacyl nitrates are formed by the reaction of peroxyacyl radicals with nitrogen dioxide (NO2). They are important air pollutants due to their attributes as eye irritants and their phytotoxic effects on plants.</p> Signup and view all the answers

<p>Nitrate radicals contribute to smog formation at night by reacting with various atmospheric components, which can enhance the persistence and reactivity of smog-forming chemicals.</p> Signup and view all the answers

<p>Aldehydes react with hydroxyl radicals, producing HOO and other oxidized products that can further participate in chain reactions leading to smog formation.</p> Signup and view all the answers

<p>Hydroxyl radicals rapidly add to double bonds in alkenes, forming radical adducts that can further react to produce oxidized products, thus facilitating smog formation.</p> Signup and view all the answers

<p>NO2 can be photolyzed by sunlight (hν) to produce NO and O, re-initiating the chain reactions necessary for continued smog formation.</p> Signup and view all the answers

<p>Hydrogen abstraction from alkanes by hydroxyl radicals leads to the formation of free radicals that can react with oxygen, producing intermediate species like ROO that contribute to smog.</p> Signup and view all the answers

<p>Hydroxyl radicals oxidize CO to CO2 while generating HOO, which can further react with NO to form NO2, thus playing an integral role in smog formation.</p> Signup and view all the answers

<p>Aside from being air pollutants, peroxyacyl nitrates are mutagens and can adversely affect plant life, contributing to environmental degradation.</p> Signup and view all the answers

<p>Hydroxyl radicals are critical in propagating smog-forming reactions by converting nitrogen oxides and hydrocarbons into reactive intermediates that facilitate further reactions.</p> Signup and view all the answers