316 PROPERTIES OF ELECTRICALLY CONDUCTING SYSTEMS 



dissolved in water, the basic properties of the nitrogen come into play 

 and that compounds of a basic nature are formed similar to ammonium 

 hydroxide, which, however, are ionized only to an exceedingly small ex- 

 tent, in view of the electronegative character of the rest of the molecule. 



As has already been pointed out, the basic amides, as for example 

 potassium and sodium amides, are electrolytes in ammonia solution and, 

 from their constitutional relation to ammonia, it is to be expected that 

 solutions of these substances will exhibit basic properties in liquid am- 

 monia. This is, indeed, the case. Potassium amide, dissolved in liquid 

 ammonia, exhibits all the properties characteristic of bases. For ex- 

 ample, it reacts with acids to form salts and ammonia; thus: 



CH 3 COOH + KNH 2 = CH 3 COOK + NH 3 . 



According to Franklin, bases of this type are called ammono-bases. 

 Obviously, all basic amides belong to this class of substances. 



The ammono-bases react not only with aquo-acids but also with 

 ammono-acids. 47 Thus, an ammono-acid reacts with an ammono-base 

 to form an acid ammono-salt and ammonia, according to the equation: 



CH 3 CONH 2 + KNH 2 = CH 3 CONHK + NH 3 . 



It is interesting to note that the color reactions characteristic of indi- 

 cators are likewise found reproduced in ammonia solutions. 48 Some 

 indicators exhibit a remarkably sharp end point; as, for example, saf- 

 franine. The nature of the indicator reactions have not, as yet, been 

 studied in detail. 



In aqueous solutions, salts of weak acids and bases are hydrolyzed 

 owing to interaction between the ions of the solvent with those of the 

 dissolved salt. So, also, in ammonia solutions, the salts of very weak 

 acids and bases are ammonolyzed; that is, the salt reacts with the sol- 

 vent to form an acid and a base. Unfortunately, the extent to which 

 ammonia is ionized into H + and NH 2 ~ ions is not known. In all likeli- 

 hood, however, the concentration of these ions is extremely low, since 

 the alkali metals are soluble in liquid ammonia and remain in solution 

 for extended periods of time with only a slight reaction, according to 

 the equation: 



Na = NaNH H. 



If the concentration of the hydrogen ions were considerable, this reaction 

 should take place with great rapidity just as the corresponding reaction 

 takes place in water. That hydrolysis (or ammonolysis) actually takes 



47 Franklin and Stafford, Am. Chem. J. 28, 83 (1902). 

 8 Franklin and Kraus, Am. Chem. J. 23, 277 (1900). 





