NITROGEN 45 



way. Nitrogen is not a poisonous gas, but if an animal 

 were compelled to breathe pure nitrogen, it would die 

 because of the lack of oxygen. Some of the compounds 

 of nitrogen decompose with violence, causing explosions. 

 Nearly all of the explosives, as gunpowder, nitroglycerin, 

 and guncotton, are compounds of nitrogen. 



46. Importance. The compounds of nitrogen take an 

 important part in animal and plant life. In combination 

 with carbon, hydrogen, and other elements, it forms the 

 nitrogenous compounds present in plant and animal bod- 

 ies. These compounds are called the organic nitrogenous 

 compounds because they are capable of undergoing com- 

 bustion, and produce volatile and gaseous products when 

 burned. 



In the study of the chemistry of foods, and of soils and 

 fertilizers, the element nitrogen is given a prominent 

 place. This is because it is one of the most expensive 

 elements in commercial fertilizers, and foods which 

 contain the nitrogenous compounds are the most ex- 

 pensive. Although nitrogen is found abundantly in the 

 air, it is made use of as a plant food in an indirect way by 

 only a limited number of plants. Nitrogen forms a large 

 number of important compounds, as ammonia, nitrates, 

 nitrites, amids, and the complex organic compounds, pro- 

 teids. Some of these compounds will be studied more in 

 detail in future chapters. To the agricultural student, 

 nitrogen is one of the most important elements because of 

 the role which it plays in plant and animal economy. 



Problem /.Calculate the per cent, of N in NaNO 8 . 



Problem 2. Calculate the per cent, of N in NH 3 . 



Problem 3 Calculate the per cent, of N in (NH 4 ) 2 SO 4 . 



