Completing the following paragraph about the ammonia synthesis process, by using No MoreThan Three Words in the passage of "The Haber Process for Ammonia Synthesis". Ammonia is one of the most important chemicals being manufactured in large tonnagetoday. Its production is linked to the population explosion. Although nitrogen is generally ________1__________ , Fritz Haber showed that thermodynamically the reaction of nitrogen with hydrogen was feasible. In 1911 he discovered that some _________2_______(catalysts) would facilitate production and process development started. Ammonia synthesis from elements nitrogen and hydrogen is a reversible, __________3_________ reaction and proceeds with a decrease in the number of moles. In theory, the one-pass yield will be greater if conditions of high pressure and_______4_______ are used. However, in industry, efficiency is important, and a relatively low percentage conversion is accepted. Modern plants have tended to operate at_____5______ and _________6_______ than the early plants, since the___________7_________and ________8_______ costs have become more significant. The unconverted materials are recycled. From where do the reactants of nitrogen and hydrogen originate? The answer is generally"from coal, oil, natural gas, water and air". With natural gas as the raw material, the plants depend on _________9_____and water to produce____10___ and carbon dioxide. Air is blended into a gas stream to supply ______11_____ . Through shift reaction the carbon monoxide is then reacted with steam to produce hydrogen and _______12_____; the latter is removed and the last traces of carbon monoxide and carbon dioxide converted to_______13________ . The purified hydrogen and nitrogen with the ratio of ______14______ are compressed and fed to the ammonia synthesis loop.