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How do nitrogen oxides from coal burning form nitric acid in the atmosphere?

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coal utilization Cross-regenerative coke oven. (A) Cross section, showing the alternating arrangement of flue walls and ovens; (B) longitudinal section, showing (left) a series of combustion flues in a single flue wall and (right) part of a long, slotlike oven.

When coal is burned in power plants at high temperatures, the nitrogen and oxygen in the air react to form nitrogen oxides, including nitric oxide (NO) and nitrogen dioxide (NO $_{2}$ ).12

Once released into the atmosphere, these nitrogen oxides contribute to the formation of nitric acid (HNO $_{3}$ ) through chemical reactions with water vapor. Specifically, nitrogen dioxide reacts with water in the atmosphere to produce nitric acid, a process that is a significant contributor to acid rain. In laboratory or industrial settings, this reaction can also involve the disproportionation of nitrogen dioxide in water to form a mixture of nitrous acid and nitric acid.21