Ammonia

One of the simplest combinations of nitrogen is ammonia, a substance that has recently acquired an unusual industrial importance. Its formula is NH3 'is a strong-smelling gas that irritates the nasal mucosa. It is colorless, as are most of the gases. In nature there exists only in very small quantities. It is prepared by direct union between the nitrogen (N2) and hydrogen (H2). The possibility of producing ammonia by this method is suggested by their formula.

It is not always possible to directly combine the elements of simple substances are composed of a given substance. In this case it is possible, but the operation is not easy. Theoretical studies conducted in France by Le Chatelier showed that for ammonia from its components, the solution was necessary to subject the two large gas pressures. The tests, carried out largely confirmed the prediction of Le Chatelier, and today is manufactured by subjecting the solution of ammonia pressures between 200 and 1000 atmospheres as factories, being more convenient temperature of 500 °C, approximately.

But even with these pressures the formation is very slow, and the industry as much or more regulated activities in the maxim that "time is money" has been necessary to find ways to accelerate this process. This increase in the rate of formation of ammonia solution is to enter the gas, pressure and temperature above, in contact with iron to which was added small amounts of other substances: sodium oxide and aluminum oxide. Still, only forms 10% of ammonia could be formed if all the nitrogen unite and hydrogen, but either way, the operation is economical because the combined gases are separated ammonia and serve a new operation.
The reader will say: "But why do we need both ammonia? Do not know any important commodity in everyday life that contain ammonia." In effect to, it is. The observation is correct, and yet, ammonia is very important. Suffice it to mention two applications of ammonia to realize what we claim: ice making and preparation of nitric acid (HNO3). Nitric acid also has direct applications in everyday life, but it is essential in the manufacture of explosives, dyes, artificial silk, celluloid, pyroxyle (raw material of paint to "pyroxylin"), ete. The reader will recognize in these many products

Basic properties:
Properties Value
chemical formula NH3
molecular weight 17.0305 g/mol
phase gas (at STP)
melting point -77.73 °C
boiling point -33.33 °C
density 6.96×10-4 g/cm3 (at 25 °C)
dielectric constant 1.00622

Gas properties:
Properties Value
density 6.96×10-4 g/cm3 (at 25 °C)
vapor density 0.6 (relative to air)
molar volume 24500 cm3/mol
surface tension 0.0234 N/m
refractive index 1.355
dynamic viscosity 1×10-5 Pa s (at 25 °C)