Nitrate radical reaction with inorganic radicals

This work was intended to give information about non-photochemical processes affecting species that are involved in hydrocarbon oxidation and ozone formation, such as the hydrocarbons themselves or the active nitrogen compounds. The main part of the work was concerned with rates and products in nitrate radical reactions with various hydrocarbons. Some interest was also taken in purely inorganic reactions. 

Ozone is formed by the photolytic decomposition of NO2 yielding oxygen radicals and by the reaction sequence NO2 — HNO3 — NO3 O3. In particular, the reaction of NO2 with hydroxyl radicals to form HNO3 increases ozone concentration because two radicals, NO2- and -OH, which catalyze ozone decomposition, are removed. Other radicals are also important for ozone destruction in the stratosphere, especially chlorine oxides see Chlorine, Bromine, Iodine, Astatine Inorganic Chemistif). The mechanism of ozone destruction is complicated as there many compounds involved. Chlorine nitrate and dinitrogen pentoxide can act as reservoir species for CIO-, NO2-, and NO3- radicals. 

Most of the inorganic anions of seawater are not subject to primary photochemical processes, because their electronic excitation energies lie well above the maximum photon energy available in sea surface sunlight. Nitrate and nitrite do, however, exhibit weak transitions with meixima at 303 nm (e ax 7 mole cm ) and 355 nm (e ax = 22.5 mole" cm" ), respectively. The primary photoreactions of both of these oxyanions produce free radical products in seawater (Zafiriou and True, 1979a, b). The overall reactions are ... 

Inorganic nitrates or nitric acid are formed by several reactions in smog. Among the important reactions forming HNO3 are the reaction of N2O5 with water and the addition of hydroxyl radical to NO2. The oxidation of NO or NO2 to nitrate species may occur after absorption of gas by an aerosol droplet. Nitric acid formed by these reactions reacts with ammonia in the atmosphere to form ammonium nitrate ... 

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