Inorganic Gas Pollutants

Ammonia, NHj, is a conunon inorganic air pollutant released as a gas to the atmosphere from several sources. In addition to industrial pollution, such as from heating coal to make coke for steel making, ammonia can be added to the atmosphere by bacterial sources, from sewage treatment, and from the decay of animal wastes. Accidental releases can occur from liquid anhydrous ammonia used as an agricultural nitrogen fertilizer. 

Ammonia is strongly attracted to water, and so it is normally present in the atmosphere in water droplets. It is the only significant gaseous base in the atmosphere, so that it reacts with atmospheric acids to produce corrosive ammonium salts as shown by the following reactions  

Though not a concern as an atmospheric pollutant in the climate as a whole, hydrogen cyanide gas, HCN, can be deadly in a microatmosphere into which it has been released. The cyanide ion, CN, from HCN or cyanide salts in the body binds with ferricytochrome oxidase, the iron(III) form 

Gaseous chlorine, fluorine, and volatile fluorides are uncommon air pollutants, but very serious where they occur. Elemental chlorine, CI2, is widely produced and distributed as a water disinfectant, bleach, and industrial chemical. It is very reactive and so toxic that it was the first poisonous gas used as a military poison in World War I. Most toxic exposures of chlorine occur as the result of transportation accidents, leading to its release. 

Hydrogen chloride, HCl, can get into the atmosphere by accidental releases of the gas from the reaction of reactive chlorine-containing chemicals, such as SiCl4, with atmospheric water  

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