92 AGRICULTURAL CHEMISTRY 



applies to the entire series, and is a broader application 

 of the law of definite proportion. 



103. Importance of the Nitrogen Compounds. The 



compounds of nitrogen, particularly nitrates and ammo- 

 nium compounds, are of importance in agriculture as they 

 serve as food for plants. They are difficult to retain in 

 soils because of their solubility and the volatility of 

 ammonia. In human and animal foods, the nitrogenous 

 compounds are of importance in many ways ; hence, in 

 economic agriculture the compounds of nitrogen receive 

 special consideration. 



Problem i. How many pounds of HNO 3 can be produced from 

 100 pounds NaNO 3 ? 



Problem 2. How much H 2 SO 4 is required when TOO pounds 

 HNO 3 are made? 



Problem j. How much NH 4 OH can be produced from 10 pounds 

 of NH 4 C1? 



Problem 4. What per cent, of NH 4 OH is NH 3 ? 



