Ostwald Process (Produces Nitric Acid)
At the first stage, ammonia is oxidized in excess in the presence of platinum as catalyst to produce nitrogen monoxide. The high temperature of 850°C and pressure of 5 atmospheres is used
Nitrogen monoxide that is formed reacts with oxygen to produce nitrogen dioxide at stage two.
At the final stage, nitrogen dioxide together with excess air is dissolved in hot water at a temperature of 80°C to produce concentrated nitric acid.