Brief introduction of ammonia gas:
1, ammonia (ammonia) is an inorganic compound with the chemical formula of NH3, molecular weight of 17.03 1, density of 0.77 1g/L, and relative density of 0.597 1 (air =/kloc- This is a colorless gas with a strong pungent smell. Ammonia water can turn wet red litmus paper blue and produce a small amount of hydroxyl ions in water, which is weakly alkaline.
2. At normal temperature (critical temperature 132.4℃, critical pressure1/0.2 MPa, i.e. 1 12.2 atmospheres) and boiling point -33.5℃, it can be liquefied under pressure and easily solidified. It will be decomposed into nitrogen and hydrogen at high temperature, which has a reducing effect. Under the action of catalyst, ammonia can be oxidized to nitric oxide.
3. Ammonia gas is usually used to make liquid nitrogen, ammonia water, nitric acid, ammonium salt and amine. Ammonia can be directly synthesized from nitrogen and hydrogen, which can burn the mucosa of skin, eyes and respiratory organs. Excessive inhalation can cause lung swelling and even death.
Learning history:
People have known the smell of ammonia since ancient times. /kloc-in the 8th century, famous chemists joseph black (Scotland), Peter Wolff (Ireland), karl william scheele (Sweden/Germany) and Joseph priestley (England) discovered that nitrogen in the air could be fixed by calcium carbide to generate calcium cyanamide, and calcium cyanamide reacted with superheated steam to generate ammonia.
2. 1785, French chemist Claude Louis Bessel determined its elemental composition. Because the chemical properties of nitrogen are very inactive, the industrial production of synthetic ammonia with nitrogen and hydrogen as raw materials was once a difficult problem.
3. During the period of 1909, German chemist Haber (E.Haber, 1868- 1934) found that the reaction was carried out at 500-600℃, 17.5-20.0 MPa and osmium as catalysts.
4. In order to transform Haber's laboratory synthetic ammonia method into large-scale industrial production, German engineer Bosch (C. Bosch, 1874- 1940) improved the high-pressure synthetic ammonia initiated by Haber, found a suitable iron oxide catalyst, and realized the industrial production of synthetic ammonia, which is called "Haber-Bosch method".