260 HYDROGENATED COMPOUNDS OF NITROGEN. 



ammonium chloride) is effected by means of concentrated 

 hydrochloric acid. 



According to the figures obtained, the reaction CH 3 NO diss. 

 + H 2 = CH 2 2 NH 3 in solution, gives off + 1/0. 



The opposite reaction, the two conditions being similarly 

 comparable, absorbs 1, a result very near 1/2 observed 

 with oxamide. It is also very near the absorption of heat 

 produced in the formation of ethers. 



Eeciprocally, the fixing of the water on the oxamide (as upon 

 formamide) with the production of ammoniacal salts, gives off 

 in heat -j- 2*4 for oxamide, always like the fixing of water on 

 the ethers. 



4 We see by this that the hydration of organic compounds 

 generally gives off heat, whether we are considering the decom- 

 position of ethers dissolved in acids and dilute alcohols, the 

 transformation of amides into ammoniacal salts, the transforma- 

 tion of anhydrous acids into hydrated acids, or of the acid 

 chlorides into hydrochloric acid and dilute organic acids. 

 This is a very general result, to which attention was drawn in 

 1865, and which is confirmed and put in a definite form by the 

 present experiments. Its importance in the theory of animal 

 heat may be easily understood. From a more technical point 

 of view, this relation, and especially the values found for the 

 hydration of oxamide and formamide, may be useful in the 

 approximate calculation of the heat of formation of amidated 

 compounds capable of being employed in the manufacture of 

 explosive substances. 



