1. Ammonia And Its Uses

2. Introduction Major Constituent of the Air It is an Inactive gas But All living things require nitrogen to live , a major component in DNA, RNA, and proteins 3. Atmospheric Nitrogen Oxides of Nitrogen Soil Nitrates Ammonia Leguminous plants plant proteins Absorbed by plantsEaten by animalsAnimal proteins Decay and excretion 4. Fritz Haber was the German scientist who developed an efficient way of producing ammonia from hydrogen and atmospheric nitrogen. In 1909, Fritz Haber established the conditions under which nitrogen, N2(g), and hydrogen, H2(g), would combine using medium temperature (~ 450 C ) very high pressure (~200atm) A catalyst (Iron) The Industrial Manufacture of Ammonia The Haber process 5. The Haber process fractional distillation cracking 6. Maximum Yield of Ammonia in the shortest possible time and at minimum cost 7. N2(g) + 3H2(g) 2NH3 (g) (H = 92.4 kJmol1) As shown in the equation, the reaction Is reversible, Forward reaction producing Ammonia and the backward reaction decomposing Ammonia back to hydrogen and nitrogen gases. In order to favour the forward reaction, to produce more ammonia, we should consider the Le-Chatelier Principle. Ie: Effect of Change in Temperature Effect of Change in pressure Effect of change in concentration. 8. Effect of Change in Temperature Since the forward reaction is exothermic N2(g) + 3H2(g) 2NH3 (g) + HEAT Increasing The temperature Low yield of Ammonia So, industrialist always try to keep the temperature as low as 450 C In order to favor maximum yield of Ammonia Note: Temperature lower than this is not feasable for this reaction, as it will take too long to attain the equilibrium 9. Effect of Change in pressure Increasing the pressure causes the equilibrium position to move to the right resulting in a higher yield of Ammonia. Hence the Haber process is always operated at very high pressures of about 200 atm in order to get high yields of Ammonia N2(g) + 3H2(g) 2NH3 (g) Increasing The Pressure High yield of Ammonia Since there are more gas molecules on the left hand side of the equation (4 in total) than there are on the right hand side of the equation (2). 10. Effect of change in concentration. The raw materials, ie: Hydrogen and nitrogen gases are supplied continuously while the ammonia produced is removed continuously by liquification. N2(g) + 3H2(g) 2NH3 (g) Increasing The reactants Removing Ammonia By liquification 11. Testing For Ammonia Gas moist red litmus paper turning blue. Ammonia is the only Alkaline gas 12. It produces white fumes with Hydrochloric Acid Glass rod dipped in Hydrochloric Acid Ammonia Gas Dense white fumes NH3 (g) + HCl (g) NH4Cl (s) 13. Agricultural industries are the major users of ammonia Ammonia is a very valuable source of nitrogen that is essential for plant growth. Approximately 75% of all AMMONIA produced is converted into various ammonium compounds like Ammonium sulphate, Ammonium Nitrate and urea. These compounds are called Nitrogenous Fertilisers Uses Of Ammonia 14. Ammonia is also useful in the production of nitric acid. A mixture of ammonia and air is passed over a platinum gauze catalyst at 850 C, whereupon the ammonia is oxidized to nitric oxide. 4 NH3 + 5 O2 4 NO + 6 H2O 2 NO + O2 2NO2 The nitric oxide mixed with excess air is then allowed to react with water to form Nitric acid 4 NO2 + O2 + 2H2O 4HNO3 15. Nitric acid is not only used to make important fertilizers but also Explosives like nitroglycerine or TNT (Trinitrotoluene) Aqueous ammonia can be a great addition to a household's cleaning supplies set. It is great for eliminating stains and tarnish, and can be the ideal solution for hard-to-remove soap buildup in tubs, sinks, and bathroom tiles.