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PRACTICE ii. 



DETERMINATION OF NITROGEN IN FERTILIZERS. 



Weigh out Yz gram of each of the following materials and use 20 cc. 

 of standard hydrochloric acid in the receiver. 



(a) Ammonium sulfate. 



(b) Dried blood. 



(c) Sodium nitrate. (Use the Kjeldahl method modified for nitrates. 

 Mix 2 gm. salicylic acid with the sodium nitrate in flask and add 30 cc. 

 sulfuric acid. Use i l / 2 times the usual amount of alkali in the distillation 

 to neutralize the larger amount of sulfuric acid.) 



How would the reaction of the soil be affected by the residues left by 

 each of these materials when used to supply nitrogen for plant growth? 



