 We have previously learned about the Haber process as the industrial method to produce ammonia. Why do we need such large quantities of ammonia and why is it so important? Ammonia is used to produce fertilizers, nitric acid, and certain household cleaning products. Ammonia is also used as a starting material for explosives and many pharmaceutical products. Nitrogen is important and essential for plant growth. Although air is approximately 77% nitrogen, plants cannot breathe it in. Instead, it must be dissolved in water and absorbed through their roots. This is done naturally by lightning and by certain types of bacteria, though it does not happen often or fast enough to sustain crop growth and hence food production. Fertilizers are used to increase the nitrogen content of soil or, in other words, make it more fertile. Livestock manure has been traditionally used as natural fertilizers, but this has become too difficult provided the massive size of many crop fields. Two very common artificial fertilizers are ammonium nitrate and ammonium sulfate, and you got it, they are made from ammonia. Ammonium nitrate is made from ammonia and nitric acid. Ammonium sulfate is made from ammonia and sulfuric acid. The constant production of these fertilizers is very important to sustain global food production. Nitric acid is also manufactured from ammonia in a series of steps. First, ammonia combines with oxygen over a platinum catalyst to produce nitrogen monoxide and water. Then, nitrogen monoxide further combines with oxygen to produce nitrogen dioxide, which is a brown gas. Lastly, nitrogen dioxide and oxygen dissolve in water to form nitric acid. By combining these equations, we get this overall reaction to produce nitric acid from ammonia. Nitric acid is used in the production of ammonium nitrate and other nitrate-based fertilizers. It is also used as a starting material for many explosives, a common one being TNT or trinitrotoluene. Nitric acid is also very important for the pharmaceutical industry. It is also used to produce certain dyes. These dyes are used as food coloring in the textiles industry and even as indicators. Royal water, or aqua regia, is a mixture of one part concentrated nitric acid and three parts concentrated hydrochloric acid. In the laboratory, it is used to clean glassware, but a much more interesting application is its use in the purification of gold and platinum. Very dilute solutions of aqueous ammonia, approximately 5-10% weight by volume, are commonly sold as household cleaning products. You may have encountered household ammonia in your own kitchen and in your bathroom cleaning products. So to recap, ammonia is used for the production of cleaning products and pharmaceutical products. Even more importantly, ammonia and the fertilizers we produce with it are vital to sustaining global food production. Our world population is growing massively and without such agricultural technology, we would be even less able to prevent famines.